02846nas a2200241 4500008004100000245008500041210006900126260001200195490000600207520209000213653000802303653002502311653001902336653001302355653003002368100002002398700001702418700001902435700002002454700002402474700001702498856008902515 2020 eng d00aBCI-based sensorimotor rhythm training can affect individuated finger movements 0 aBCIbased sensorimotor rhythm training can affect individuated fi c06/20200 v73 aBrain-computer interface (BCI) technology can restore communication and control to people who are severely paralyzed. BCI technology might also be able to enhance rehabilitation of motor function. We have previously shown that pre-movement sensorimotor rhythm (SMR) amplitude affects reaction time and performance on a joystick-based cursor movement task. The present study explores in adults without motor impairment the possibility that pre-movement SMR amplitude affects performance of individuated finger movements. In Phase 1, 8 individuals performed a finger flexion task that was monitored by an exoskeleton. During a 1-sec preparatory period, two colored targets on a video monitor cued flexion of the index finger, middle finger, both fingers, or neither finger; sudden color change then triggered the movement (or non-movement). SMR features (i.e. EEG amplitudes in specific frequency bands at specific scalp locations) in the pre-movement EEG that correlated with movement versus no movement were identified. In Phase 2, the participants learned to increase or decrease these SMR features to control a two-target BCI task. Finally, in Phase 3, they were asked to increase or decrease the SMR features to initiate the finger flexion task of Phase 1 and the impact on finger flexion performance was assessed. After BCI training, pre-movement SMR feature amplitude affected performance in a subset of individuals: lower amplitude was associated with shorter movement onset. In a subset of individuals, the beneficial effect on performance of lower SMR amplitude was greater when both fingers were flexed than when one was flexed and the other remained extended; thus, the impact of SMR amplitude modulation depended on the specificity of the subsequent motor task. These results indicate that BCI-based training of SMR activity in the pre-movement preparatory period can affect finger movements in a subset of individuals. They encourage studies that integrate such training into rehabilitation protocols and examine its capacity to enhance restoration of useful hand function.10aBCI10amovement preparation10aRehabilitation10aRobotics10asensorimotor beta rhythms1 aMcFarland, D.J.1 aNorman, S.L.1 aSarnacki, W.A.1 aWolbrecht, E.T.1 aReinkensmeyer, D.J.1 aWolpaw, J.R. uhttps://www.tandfonline.com/doi/abs/10.1080/2326263X.2020.1763060?journalCode=tbci2001263nas a2200253 4500008004100000245006000041210005900101260001200160490000800172520057900180653000800759653000800767653001300775653002500788653001900813100001400832700001500846700001500861700001500876700001700891700001200908700001700920856007200937 2020 eng d00aOperant Condition of the Flexor Carpi Radialis H-reflex0 aOperant Condition of the Flexor Carpi Radialis Hreflex c12/20200 v1013 aOperant conditioning of the largely monosynaptic H-reflex is a targeted and non-invasive therapeutic intervention for people with motor dysfunction after spinal cord injury and possibly stroke.1,2,3 It can complement other therapies and has no known adverse side effects. To date, H-reflex operant conditioning has focused on the leg. Here, we extend it to the arm by asking participants to either increase or decrease the flexor carpi radialis (FCR) H-reflex. In addition, we examine concurrent changes in brain activity by recording electroencephalographic activity (EEG).10aBCI10aFCR10aH-Reflex10aoperant conditioning10aRehabilitation1 aNorton, J1 aVaughan, T1 aGemoets, D1 aHeckman, S1 aToliou, S.D.1 aCarp, J1 aWolpaw, J.R. uhttps://www.archives-pmr.org/article/S0003-9993(20)31081-9/abstract02706nas a2200265 4500008004100000245009100041210006900132260001200201490000700213520195600220653000802176653001802184653001902202653001002221653002402231653001102255100001502266700001802281700001302299700001502312700001802327700002102345700002202366856005202388 2018 eng d00aControlling pre-movement sensorimotor rhythm can improve finger extension after stroke0 aControlling premovement sensorimotor rhythm can improve finger e c08/20180 v153 aObjective. Brain–computer interface (BCI) technology is attracting increasing interest as a tool for enhancing recovery of motor function after stroke, yet the optimal way to apply this technology is unknown. Here, we studied the immediate and therapeutic effects of BCI-based training to control pre-movement sensorimotor rhythm (SMR) amplitude on robot-assisted finger extension in people with stroke. Approach. Eight people with moderate to severe hand impairment due to chronic stroke completed a four-week three-phase protocol during which they practiced finger extension with assistance from the FINGER robotic exoskeleton. In Phase 1, we identified spatiospectral SMR features for each person that correlated with the intent to extend the index and/or middle finger(s). In Phase 2, the participants learned to increase or decrease SMR features given visual feedback, without movement. In Phase 3, the participants were cued to increase or decrease their SMR features, and when successful, were then cued to immediately attempt to extend the finger(s) with robot assistance. Main results. Of the four participants that achieved SMR control in Phase 2, three initiated finger extensions with a reduced reaction time after decreasing (versus increasing) pre-movement SMR amplitude during Phase 3. Two also extended at least one of their fingers more forcefully after decreasing pre-movement SMR amplitude. Hand function, measured by the box and block test (BBT), improved by 7.3  ±  7.5 blocks versus 3.5  ±  3.1 blocks in those with and without SMR control, respectively. Higher BBT scores at baseline correlated with a larger change in BBT score. Significance. These results suggest that learning to control person-specific pre-movement SMR features associated with finger extension can improve finger extension ability after stroke for some individuals. These results merit further investigation in a rehabilitation context.10aBCI10aMotor control10aRehabilitation10arobot10asensorimotor rhythm10aStroke1 aNorman, SL1 aMcFarland, DJ1 aMiner, A1 aCramer, SC1 aWolbrecht, ET1 aWolpaw, Jonathan1 aReinkensmeyer, DJ uhttp://stacks.iop.org/1741-2552/15/i=5/a=05602601870nas a2200265 4500008004100000022001400041245008400055210006900139260001200208300001200220490000700232520108800239653002501327653001301352653002701365653002501392653001501417653001901432653001801451100001601469700001601485700001801501700002101519856006401540 2018 eng d a1878-747900aRetraining Reflexes: Clinical Translation of Spinal Reflex Operant Conditioning0 aRetraining Reflexes Clinical Translation of Spinal Reflex Operan c07/2018 a669-6830 v153 aNeurological disorders, such as spinal cord injury, stroke, traumatic brain injury, cerebral palsy, and multiple sclerosis cause motor impairments that are a huge burden at the individual, family, and societal levels. Spinal reflex abnormalities contribute to these impairments. Spinal reflex measurements play important roles in characterizing and monitoring neurological disorders and their associated motor impairments, such as spasticity, which affects nearly half of those with neurological disorders. Spinal reflexes can also serve as therapeutic targets themselves. Operant conditioning protocols can target beneficial plasticity to key reflex pathways; they can thereby trigger wider plasticity that improves impaired motor skills, such as locomotion. These protocols may complement standard therapies such as locomotor training and enhance functional recovery. This paper reviews the value of spinal reflexes and the therapeutic promise of spinal reflex operant conditioning protocols; it also considers the complex process of translating this promise into clinical reality.10aclinical translation10aH-Reflex10aneurological disorders10aoperant conditioning10aplasticity10aRehabilitation10aspinal reflex1 aEftekhar, A1 aNorton, JJS1 aMcDonough, CM1 aWolpaw, Jonathan uhttps://link.springer.com/article/10.1007/s13311-018-0643-201542nas a2200193 4500008004100000022001400041245004000055210003800095260000800133300001200141490000600153520102900159653002901188653002001217653001901237100002201256700002101278856004901299 2017 eng d a2468-451100aEEG-based brain-computer interfaces0 aEEGbased braincomputer interfaces cOct a194-2000 v43 aBrain–Computer Interfaces (BCIs) are real-time computer-based systems that translate brain signals into useful commands. To date most applications have been demonstrations of proof-of-principle; widespread use by people who could benefit from this technology requires further development. Improvements in current EEG recording technology are needed. Better sensors would be easier to apply, more comfortable for the user, and produce higher quality and more stable signals. Although considerable effort has been devoted to evaluating classifiers using public datasets, more attention to real-time signal processing issues and to optimizing the mutually adaptive interaction between the brain and the BCI are essential for improving BCI performance. Further development of applications is also needed, particularly applications of BCI technology to rehabilitation. The design of rehabilitation applications hinges on the nature of BCI control and how it might be used to induce and guide beneficial plasticity in the brain.10abrain-computer interface10aneurotechnology10aRehabilitation1 aMcFarland, D., J.1 aWolpaw, Jonathan uhttps://www.ncbi.nlm.nih.gov/pubmed/2143819302131nas a2200253 4500008004100000245007200041210006900113260000900182300001400191490000700205520141800212653001301630653001901643653002501662653001501687653001901702653001601721100001301737700001301750700001301763700002201776700002101798856005801819 2017 eng d00aWhy New Spinal Cord Plasticity Does Not Disrupt Old Motor Behaviors0 aWhy New Spinal Cord Plasticity Does Not Disrupt Old Motor Behavi cJuly a8198-82060 v373 aWhen new motor learning changes the spinal cord, old behaviors are not impaired; their key features are preserved by additional compensatory plasticity. To explore the mechanisms responsible for this compensatory plasticity, we transected the spinal dorsal ascending tract before or after female rats acquired a new behavior—operantly conditioned increase or decrease in the right soleus H-reflex—and examined an old behavior—locomotion. Neither spinal dorsal ascending tract transection nor H-reflex conditioning alone impaired locomotion. Nevertheless, when spinal dorsal ascending tract transection and H-reflex conditioning were combined, the rats developed a limp and a tilted posture that correlated in direction and magnitude with the H-reflex change. When the right H-reflex was increased by conditioning, the right step lasted longer than the left and the right hip was higher than the left; when the right H-reflex was decreased by conditioning, the opposite occurred. These results indicate that ascending sensory input guides the compensatory plasticity that normally prevents the plasticity underlying H-reflex change from impairing locomotion. They support the concept of the state of the spinal cord as a negotiated equilibrium that reflects the concurrent influences of all the behaviors in an individual's repertoire; and they support the new therapeutic strategies this concept introduces.10aH-Reflex10amotor learning10aoperant conditioning10aplasticity10aRehabilitation10aSpinal Cord1 aChen, Yi1 aChen, Lu1 aWang, Yu1 aChen, Xiang, Yang1 aWolpaw, Jonathan uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5566867/02012nas a2200229 4500008004100000022001400041245004900055210004800104260001200152300001100164490000800175520137600183653003401559653001301593653002501606653001901631653002301650653001801673100002201691700002101713856004801734 2015 eng d a1875-785500aTargeted neuroplasticity for rehabilitation.0 aTargeted neuroplasticity for rehabilitation c03/2015 a157-720 v2183 a

An operant-conditioning protocol that bases reward on the electromyographic response produced by a specific CNS pathway can change that pathway. For example, in both animals and people, an operant-conditioning protocol can increase or decrease the spinal stretch reflex or its electrical analog, the H-reflex. Reflex change is associated with plasticity in the pathway of the reflex as well as elsewhere in the spinal cord and brain. Because these pathways serve many different behaviors, the plasticity produced by this conditioning can change other behaviors. Thus, in animals or people with partial spinal cord injuries, appropriate reflex conditioning can improve locomotion. Furthermore, in people with spinal cord injuries, appropriate reflex conditioning can trigger widespread beneficial plasticity. This wider plasticity appears to reflect an iterative process through which the multiple behaviors in the individual's repertoire negotiate the properties of the spinal neurons and synapses that they all use. Operant-conditioning protocols are a promising new therapeutic method that could complement other rehabilitation methods and enhance functional recovery. Their successful use requires strict adherence to appropriately designed procedures, as well as close attention to accommodating and engaging the individual subject in the conditioning process.

10aactivity-dependent plasticity10aH-Reflex10aoperant conditioning10aRehabilitation10aspinal cord injury10aspinal reflex1 aThompson, Aiko, K1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/2589013602554nas a2200241 4500008004100000022001400041245016400055210006900219260001200288300001200300490000800312520178000320653001302100653001502113653001902128653001602147653001502163100002102178700002202199700002102221700002202242856004802264 2014 eng d a1522-159800aOperant conditioning of the soleus H-reflex does not induce long-term changes in the gastrocnemius H-reflexes and does not disturb normal locomotion in humans.0 aOperant conditioning of the soleus Hreflex does not induce longt c09/2014 a1439-460 v1123 a

In normal animals, operant conditioning of the spinal stretch reflex or the H-reflex has lesser effects on synergist muscle reflexes. In rats and people with incomplete spinal cord injury (SCI), soleus H-reflex operant conditioning can improve locomotion. We studied in normal humans the impact of soleus H-reflex down-conditioning on medial (MG) and lateral gastrocnemius (LG) H-reflexes and on locomotion. Subjects completed 6 baseline and 30 conditioning sessions. During conditioning trials, the subject was encouraged to decrease soleus H-reflex size with the aid of visual feedback. Every sixth session, MG and LG H-reflexes were measured. Locomotion was assessed before and after conditioning. In successfully conditioned subjects, the soleus H-reflex decreased 27.2%. This was the sum of within-session (task dependent) adaptation (13.2%) and across-session (long term) change (14%). The MG H-reflex decreased 14.5%, due mainly to task-dependent adaptation (13.4%). The LG H-reflex showed no task-dependent adaptation or long-term change. No consistent changes were detected across subjects in locomotor H-reflexes, EMG activity, joint angles, or step symmetry. Thus, in normal humans, soleus H-reflex down-conditioning does not induce long-term changes in MG/LG H-reflexes and does not change locomotion. In these subjects, task-dependent adaptation of the soleus H-reflex is greater than it is in people with SCI, whereas long-term change is less. This difference from results in people with SCI is consistent with the fact that long-term change is beneficial in people with SCI, since it improves locomotion. In contrast, in normal subjects, long-term change is not beneficial and may necessitate compensatory plasticity to preserve satisfactory locomotion.

10aLearning10aplasticity10aRehabilitation10aSpinal Cord10asynergists1 aMakihara, Yukiko1 aSegal, Richard, L1 aWolpaw, Jonathan1 aThompson, Aiko, K uhttp://www.ncbi.nlm.nih.gov/pubmed/2494421602425nas a2200289 4500008004100000022001400041245008700055210006900142260001200211300001200223490000800235520161100243653002601854653001301880653001501893653001101908653001801919653001901937653002301956653002701979100001302006700001302019700001302032700002102045700002102066856004802087 2014 eng d a1522-159800aPersistent beneficial impact of H-reflex conditioning in spinal cord-injured rats.0 aPersistent beneficial impact of Hreflex conditioning in spinal c c11/2014 a2374-810 v1123 a

Operant conditioning of a spinal cord reflex can improve locomotion in rats and humans with incomplete spinal cord injury. This study examined the persistence of its beneficial effects. In rats in which a right lateral column contusion injury had produced asymmetric locomotion, up-conditioning of the right soleus H-reflex eliminated the asymmetry while down-conditioning had no effect. After the 50-day conditioning period ended, the H-reflex was monitored for 100 [±9 (SD)] (range 79-108) more days and locomotion was then reevaluated. After conditioning ended in up-conditioned rats, the H-reflex continued to increase, and locomotion continued to improve. In down-conditioned rats, the H-reflex decrease gradually disappeared after conditioning ended, and locomotion at the end of data collection remained as impaired as it had been before and immediately after down-conditioning. The persistence (and further progression) of H-reflex increase but not H-reflex decrease in these spinal cord-injured rats is consistent with the fact that up-conditioning improved their locomotion while down-conditioning did not. That is, even after up-conditioning ended, the up-conditioned H-reflex pathway remained adaptive because it improved locomotion. The persistence and further enhancement of the locomotor improvement indicates that spinal reflex conditioning protocols might supplement current therapies and enhance neurorehabilitation. They may be especially useful when significant spinal cord regeneration becomes possible and precise methods for retraining the regenerated spinal cord are needed.

10aH-reflex conditioning10aLearning10aLocomotion10aMemory10aMotor control10aRehabilitation10aspinal cord injury10aspinal cord plasticity1 aChen, Yi1 aChen, Lu1 aWang, Yu1 aWolpaw, Jonathan1 aChen, Xiang Yang uhttp://www.ncbi.nlm.nih.gov/pubmed/2514354202449nas a2200241 4500008004100000022001400041245010300055210006900158260001200227300001600239490000700255520172600262653001301988653001502001653002502016653001502041653001902056653001502075100002302090700002502113700002102138856004802159 2013 eng d a1529-240100aOperant conditioning of a spinal reflex can improve locomotion after spinal cord injury in humans.0 aOperant conditioning of a spinal reflex can improve locomotion a c02/2013 a2365–23750 v333 aOperant conditioning protocols can modify the activity of specific spinal cord pathways and can thereby affect behaviors that use these pathways. To explore the therapeutic application of these protocols, we studied the impact of down-conditioning the soleus H-reflex in people with impaired locomotion caused by chronic incomplete spinal cord injury. After a baseline period in which soleus H-reflex size was measured and locomotion was assessed, subjects completed either 30 H-reflex down-conditioning sessions (DC subjects) or 30 sessions in which the H-reflex was simply measured [unconditioned (UC) subjects], and locomotion was reassessed. Over the 30 sessions, the soleus H-reflex decreased in two-thirds of the DC subjects (a success rate similar to that in normal subjects) and remained smaller several months later. In these subjects, locomotion became faster and more symmetrical, and the modulation of EMG activity across the step cycle increased bilaterally. Furthermore, beginning about halfway through the conditioning sessions, all of these subjects commented spontaneously that they were walking faster and farther in their daily lives, and several noted less clonus, easier stepping, and/or other improvements. The H-reflex did not decrease in the other DC subjects or in any of the UC subjects; and their locomotion did not improve. These results suggest that reflex-conditioning protocols can enhance recovery of function after incomplete spinal cord injuries and possibly in other disorders as well. Because they are able to target specific spinal pathways, these protocols could be designed to address each individual's particular deficits, and might thereby complement other rehabilitation methods.10aLearning10aLocomotion10aoperant conditioning10aplasticity10aRehabilitation10aspasticity1 aThompson, Aiko, K.1 aPomerantz, Ferne, R.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/2339266601657nas a2200217 4500008004100000022001400041245008100055210006900136260001200205300001400217490000700231520101900238653001901257653001501276653001901291653001601310100002301326700002101349700002101370856004801391 2013 eng d a1097-459800aSoleus H-reflex operant conditioning changes the H-reflex recruitment curve.0 aSoleus Hreflex operant conditioning changes the Hreflex recruitm c04/2013 a539–5440 v473 aINTRODUCTION: Operant conditioning can gradually change the human soleus H-reflex. The protocol conditions the reflex near M-wave threshold. In this study we examine its impact on the reflexes at other stimulus strengths. METHODS: H-reflex recruitment curves were obtained before and after a 24-session exposure to an up-conditioning (HRup) or a down-conditioning (HRdown) protocol and were compared. RESULTS: In both HRup and HRdown subjects, conditioning affected the entire H-reflex recruitment curve. In 5 of 6 HRup and 3 of 6 HRdown subjects, conditioning elevated (HRup) or depressed (HRdown), respectively, the entire curve. In the other HRup subject or the other 3 HRdown subjects, the curve was shifted to the left or to the right, respectively. CONCLUSIONS: H-reflex conditioning does not simply change the H-reflex to a stimulus of particular strength; it also changes the H-reflexes to stimuli of different strengths. Thus, it is likely to affect many actions in which this pathway participates.10amotor learning10aplasticity10aRehabilitation10aSpinal Cord1 aThompson, Aiko, K.1 aChen, Xiang Yang1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/2328110702444nas a2200325 4500008004100000022001400041245011200055210006900167260001200236300001600248490000800264520147000272653002901742653002801771653000801799653002801807653000901835653001901844100001701863700002001880700002501900700002301925700001701948700001901965700002101984700002402005700002102029700002002050856004802070 2010 eng d a1872-895200aA novel P300-based brain-computer interface stimulus presentation paradigm: moving beyond rows and columns.0 anovel P300based braincomputer interface stimulus presentation pa c07/2010 a1109–11200 v1213 aOBJECTIVE: An electroencephalographic brain-computer interface (BCI) can provide a non-muscular means of communication for people with amyotrophic lateral sclerosis (ALS) or other neuromuscular disorders. We present a novel P300-based BCI stimulus presentation - the checkerboard paradigm (CBP). CBP performance is compared to that of the standard row/column paradigm (RCP) introduced by Farwell and Donchin (1988). METHODS: Using an 8x9 matrix of alphanumeric characters and keyboard commands, 18 participants used the CBP and RCP in counter-balanced fashion. With approximately 9-12 min of calibration data, we used a stepwise linear discriminant analysis for online classification of subsequent data. RESULTS: Mean online accuracy was significantly higher for the CBP, 92%, than for the RCP, 77%. Correcting for extra selections due to errors, mean bit rate was also significantly higher for the CBP, 23 bits/min, than for the RCP, 17 bits/min. Moreover, the two paradigms produced significantly different waveforms. Initial tests with three advanced ALS participants produced similar results. Furthermore, these individuals preferred the CBP to the RCP. CONCLUSIONS: These results suggest that the CBP is markedly superior to the RCP in performance and user acceptability. SIGNIFICANCE: The CBP has the potential to provide a substantially more effective BCI than the RCP. This is especially important for people with severe neuromuscular disabilities.10abrain-computer interface10abrain-machine interface10aEEG10aevent-related potential10aP30010aRehabilitation1 aTownsend, G.1 aLaPallo, B., K.1 aBoulay, Chadwick, B.1 aKrusienski, D., J.1 aFrye, G., E.1 aHauser, C., K.1 aSchwartz, N., E.1 aVaughan, Theresa, M1 aWolpaw, Jonathan1 aSellers, E., W. uhttp://www.ncbi.nlm.nih.gov/pubmed/2034738701519nas a2200301 4500008004100000022001400041245009500055210006900150260001200219300001400231490001700245520064100262653001300903653002400916653001500940653001500955653002400970653001900994653002301013100002101036700001301057700001301070700001901083700002301102700002301125700002101148856004801169 2010 eng d a1749-663200aReflex conditioning: a new strategy for improving motor function after spinal cord injury.0 aReflex conditioning a new strategy for improving motor function  c06/2010 aE12–E210 v1198 Suppl 13 aSpinal reflex conditioning changes reflex size, induces spinal cord plasticity, and modifies locomotion. Appropriate reflex conditioning can improve walking in rats after spinal cord injury (SCI). Reflex conditioning offers a new therapeutic strategy for restoring function in people with SCI. This approach can address the specific deficits of individuals with SCI by targeting specific reflex pathways for increased or decreased responsiveness. In addition, once clinically significant regeneration can be achieved, reflex conditioning could provide a means of reeducating the newly (and probably imperfectly) reconnected spinal cord.10aH-Reflex10alearning and memory10aLocomotion10aplasticity10areflex conditioning10aRehabilitation10aspinal cord injury1 aChen, Xiang Yang1 aChen, Yi1 aWang, Yu1 aThompson, Aiko1 aCarp, Jonathan, S.1 aSegal, Richard, L.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/2059053401326nas a2200265 4500008004100000022001400041245005600055210005400111260000900165300001300174490000900187520048800196653001500684653001000699653002400709653002100733653003100754653001900785653003100804653003200835653004100867653002800908100001900936856010500955 2009 eng d a1557-170X00aEffective brain-computer interfacing using BCI2000.0 aEffective braincomputer interfacing using BCI2000 c2009 a5498-5010 v20093 aTo facilitate research and development in Brain-Computer Interface (BCI) research, we have been developing a general-purpose BCI system, called BCI2000, over the past nine years. This system has enjoyed a growing adoption in BCI and related areas and has been the basis for some of the most impressive studies reported to date. This paper gives an update on the status of this project by describing the principles of the BCI2000 system, its benefits, and impact on the field to date.10aAlgorithms10aBrain10aElectrocardiography10aEquipment Design10aEquipment Failure Analysis10aRehabilitation10aReproducibility of Results10aSensitivity and Specificity10aSignal Processing, Computer-Assisted10aUser-Computer Interface1 aSchalk, Gerwin uhttps://www.neurotechcenter.org/publications/2009/effective-brain-computer-interfacing-using-bci200002473nas a2200289 4500008004100000022001400041245007500055210006900130260001200199300001600211490000800227520163800235653002901873653002801902653000801930653002801938653000901966653001901975100002101994700002402015700001902039700002102058700002102079700001502100700002002115856004802135 2009 eng d a1872-895200aToward a high-throughput auditory P300-based brain-computer interface.0 aToward a highthroughput auditory P300based braincomputer interfa c07/2009 a1252–12610 v1203 aOBJECTIVE: Brain-computer interface (BCI) technology can provide severely disabled people with non-muscular communication. For those most severely disabled, limitations in eye mobility or visual acuity may necessitate auditory BCI systems. The present study investigates the efficacy of the use of six environmental sounds to operate a 6x6 P300 Speller. METHODS: A two-group design was used to ascertain whether participants benefited from visual cues early in training. Group A (N=5) received only auditory stimuli during all 11 sessions, whereas Group AV (N=5) received simultaneous auditory and visual stimuli in initial sessions after which the visual stimuli were systematically removed. Stepwise linear discriminant analysis determined the matrix item that elicited the largest P300 response and thereby identified the desired choice. RESULTS: Online results and offline analyses showed that the two groups achieved equivalent accuracy. In the last session, eight of 10 participants achieved 50% or more, and four of these achieved 75% or more, online accuracy (2.8% accuracy expected by chance). Mean bit rates averaged about 2 bits/min, and maximum bit rates reached 5.6 bits/min. CONCLUSIONS: This study indicates that an auditory P300 BCI is feasible, that reasonable classification accuracy and rate of communication are achievable, and that the paradigm should be further evaluated with a group of severely disabled participants who have limited visual mobility. SIGNIFICANCE: With further development, this auditory P300 BCI could be of substantial value to severely disabled people who cannot use a visual BCI.10abrain-computer interface10abrain-machine interface10aEEG10aevent-related potential10aP30010aRehabilitation1 aKlobassa, D., S.1 aVaughan, Theresa, M1 aBrunner, Peter1 aSchwartz, N., E.1 aWolpaw, Jonathan1 aNeuper, C.1 aSellers, E., W. uhttp://www.ncbi.nlm.nih.gov/pubmed/1957409102392nas a2200361 4500008004100000022001400041245008900055210006900144260001200213300001600225490000800241520135100249653003401600653002901634653002501663653002901688653000901717653001901726100001601745700002001761700001701781700001901798700001301817700001901830700001401849700001501863700002301878700002401901700002101925700002101946700001501967856004801982 2008 eng d a1388-245700aA P300-based brain-computer interface for people with amyotrophic lateral sclerosis.0 aP300based braincomputer interface for people with amyotrophic la c08/2008 a1909–19160 v1193 aOBJECTIVE: The current study evaluates the efficacy of a P300-based brain-computer interface (BCI) communication device for individuals with advanced ALS. METHODS: Participants attended to one cell of a N x N matrix while the N rows and N columns flashed randomly. Each cell of the matrix contained one character. Every flash of an attended character served as a rare event in an oddball sequence and elicited a P300 response. Classification coefficients derived using a stepwise linear discriminant function were applied to the data after each set of flashes. The character receiving the highest discriminant score was presented as feedback. RESULTS: In Phase I, six participants used a 6 x 6 matrix on 12 separate days with a mean rate of 1.2 selections/min and mean online and offline accuracies of 62% and 82%, respectively. In Phase II, four participants used either a 6 x 6 or a 7 x 7 matrix to produce novel and spontaneous statements with a mean online rate of 2.1 selections/min and online accuracy of 79%. The amplitude and latency of the P300 remained stable over 40 weeks. CONCLUSIONS: Participants could communicate with the P300-based BCI and performance was stable over many months. SIGNIFICANCE: BCIs could provide an alternative communication and control technology in the daily lives of people severely disabled by ALS.10aAmyotrophic Lateral Sclerosis10abrain-computer interface10aelectroencephalogram10aevent-related potentials10aP30010aRehabilitation1 aNijboer, F.1 aSellers, E., W.1 aMellinger, J1 aJordan, M., A.1 aMatuz, T1 aFurdea, Adrian1 aHalder, S1 aMochty, U.1 aKrusienski, D., J.1 aVaughan, Theresa, M1 aWolpaw, Jonathan1 aBirbaumer, Niels1 aKübler, A uhttp://www.ncbi.nlm.nih.gov/pubmed/1857198402003nas a2200241 4500008004100000022001400041245007500055210006900130260001200199300001400211490000800225520132900233653001701562653001301579653001301592653001101605653001901616653001501635653001901650653002301669100002101692856004801713 2007 eng d a1748-170800aSpinal cord plasticity in acquisition and maintenance of motor skills.0 aSpinal cord plasticity in acquisition and maintenance of motor s c02/2007 a155–1690 v1893 aThroughout normal life, activity-dependent plasticity occurs in the spinal cord as well as in brain. Like other central nervous system (CNS) plasticity, spinal cord plasticity can occur at numerous neuronal and synaptic sites and through a variety of mechanisms. Spinal cord plasticity is prominent early in life and contributes to mastery of standard behaviours like locomotion and rapid withdrawal from pain. Later in life, spinal cord plasticity has a role in acquisition and maintenance of new motor skills, and in compensation for peripheral and central changes accompanying ageing, disease and trauma. Mastery of the simplest behaviours is accompanied by complex spinal and supraspinal plasticity. This complexity is necessary, in order to preserve the complete behavioural repertoire, and is also inevitable, due to the ubiquity of activity-dependent CNS plasticity. Explorations of spinal cord plasticity are necessary for understanding motor skills. Furthermore, the spinal cord's comparative simplicity and accessibility makes it a logical starting point for studying skill acquisition. Induction and guidance of activity-dependent spinal cord plasticity will probably play an important role in realization of effective new rehabilitation methods for spinal cord injuries, cerebral palsy and other motor disorders.10aconditioning10aH-Reflex10aLearning10aMemory10amotor function10aplasticity10aRehabilitation10aspinal cord injury1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1725056601530nas a2200277 4500008004100000022001400041245006600055210006500121260001200186300001400198490000700212520068900219653003500908653003300943653001900976100002100995700002101016700002501037700002101062700003001083700002701113700001901140700002301159700002201182856004801204 2006 eng d a1534-432000aBCI Meeting 2005–workshop on signals and recording methods.0 aBCI Meeting 2005–workshop on signals and recording methods c06/2006 a138–1410 v143 aThis paper describes the highlights of presentations and discussions during the Third International BCI Meeting in a workshop that evaluated potential brain-computer interface (BCI) signals and currently available recording methods. It defined the main potential user populations and their needs, addressed the relative advantages and disadvantages of noninvasive and implanted (i.e., invasive) methodologies, considered ethical issues, and focused on the challenges involved in translating BCI systems from the laboratory to widespread clinical use. The workshop stressed the critical importance of developing useful applications that establish the practical value of BCI technology.10aBrain-computer interface (BCI)10aelectrophysiological signals10aRehabilitation1 aWolpaw, Jonathan1 aLoeb, Gerald, E.1 aAllison, Brendan, Z.1 aDonchin, Emanuel1 aNascimento, Omar, Feix do1 aHeetderks, William, J.1 aNijboer, Femke1 aShain, William, G.1 aTurner, James, N. uhttp://www.ncbi.nlm.nih.gov/pubmed/1679227901903nas a2200301 4500008004100000022001400041245010700055210006900162260001200231300001800243490000700261520101900268653002601287653001301313653001501326653001101341653001801352653001901370653002301389653002701412100001301439700002101452700002101473700001301494700002501507700002101532856004801553 2006 eng d a1529-240100aOperant conditioning of H-reflex can correct a locomotor abnormality after spinal cord injury in rats.0 aOperant conditioning of Hreflex can correct a locomotor abnormal c11/2006 a12537–125430 v263 a

This study asked whether operant conditioning of the H-reflex can modify locomotion in spinal cord-injured rats. Midthoracic transection of the right lateral column of the spinal cord produced a persistent asymmetry in the muscle activity underlying treadmill locomotion. The rats were then either exposed or not exposed to an H-reflex up-conditioning protocol that greatly increased right soleus motoneuron response to primary afferent input, and locomotion was reevaluated. H-reflex up-conditioning increased the right soleus burst and corrected the locomotor asymmetry. In contrast, the locomotor asymmetry persisted in the control rats. These results suggest that appropriately selected reflex conditioning protocols might improve function in people with partial spinal cord injuries. Such protocols might be especially useful when significant regeneration becomes possible and precise methods for reeducating the regenerated spinal cord neurons and synapses are needed for restoring effective function.

10aH-reflex conditioning10aLearning10aLocomotion10aMemory10aMotor control10aRehabilitation10aspinal cord injury10aspinal cord plasticity1 aChen, Yi1 aChen, Xiang Yang1 aJakeman, Lyn, B.1 aChen, Lu1 aStokes, Bradford, T.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1713541502016nas a2200265 4500008004100000022001400041245013800055210006900193260001200262300001400274490000700288520114400295653003401439653002901473653002501502653002901527653000901556653001901565100002201584700002501606700002601631700002401657700002101681856004801702 2006 eng d a0301-051100aA P300 event-related potential brain-computer interface (BCI): the effects of matrix size and inter stimulus interval on performance.0 aP300 eventrelated potential braincomputer interface BCI the effe c10/2006 a242–2520 v733 aWe describe a study designed to assess properties of a P300 brain-computer interface (BCI). The BCI presents the user with a matrix containing letters and numbers. The user attends to a character to be communicated and the rows and columns of the matrix briefly intensify. Each time the attended character is intensified it serves as a rare event in an oddball sequence and it elicits a P300 response. The BCI works by detecting which character elicited a P300 response. We manipulated the size of the character matrix (either 3 x 3 or 6 x 6) and the duration of the inter stimulus interval (ISI) between intensifications (either 175 or 350 ms). Online accuracy was highest for the 3 x 3 matrix 175-ms ISI condition, while bit rate was highest for the 6 x 6 matrix 175-ms ISI condition. Average accuracy in the best condition for each subject was 88%. P300 amplitude was significantly greater for the attended stimulus and for the 6 x 6 matrix. This work demonstrates that matrix size and ISI are important variables to consider when optimizing a BCI system for individual users and that a P300-BCI can be used for effective communication.10aAmyotrophic Lateral Sclerosis10abrain-computer interface10aelectroencephalogram10aevent-related potentials10aP30010aRehabilitation1 aSellers, Eric, W.1 aKrusienski, Dean, J.1 aMcFarland, Dennis, J.1 aVaughan, Theresa, M1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1686092002708nas a2200289 4500008004100000022001400041245010300055210006900158260001200227300001600239490000700255520184500262653002602107653001302133653001502146653002502161653001802186653001902204653002702223100001302250700002102263700002102284700001902305700002502324700002102349856004802370 2005 eng d a1529-240100aThe interaction of a new motor skill and an old one: H-reflex conditioning and locomotion in rats.0 ainteraction of a new motor skill and an old one Hreflex conditio c07/2005 a6898–69060 v253 aNew and old motor skills can interfere with each other or interact in other ways. Because each skill entails a distributed pattern of activity-dependent plasticity, investigation of their interactions is facilitated by simple models. In a well characterized model of simple learning, rats and monkeys gradually change the size of the H-reflex, the electrical analog of the spinal stretch reflex. This study evaluates in normal rats the interactions of this new skill of H-reflex conditioning with the old well established skill of overground locomotion. In rats in which the soleus H-reflex elicited in the conditioning protocol (i.e., the conditioning H-reflex) had been decreased by down-conditioning, the H-reflexes elicited during the stance and swing phases of locomotion (i.e., the locomotor H-reflexes) were also smaller. Similarly, in rats in which the conditioning H-reflex had been increased by up-conditioning, the locomotor H-reflexes were also larger. Soleus H-reflex conditioning did not affect the duration, length, or right/left symmetry of the step cycle. However, the conditioned change in the stance H-reflex was positively correlated with change in the amplitude of the soleus locomotor burst, and the correlation was consistent with current estimates of the contribution of primary afferent input to the burst. Although H-reflex conditioning and locomotion did not interfere with each other, H-reflex conditioning did affect how locomotion was produced: it changed soleus burst amplitude and may have induced compensatory changes in the activity of other muscles. These results illustrate and clarify the subtlety and complexity of skill interactions. They also suggest that H-reflex conditioning might be used to improve the abnormal locomotion produced by spinal cord injury or other disorders of supraspinal control.10aH-reflex conditioning10aLearning10aLocomotion10amemory consolidation10aMotor control10aRehabilitation10aspinal cord plasticity1 aChen, Yi1 aChen, Xiang Yang1 aJakeman, Lyn, B.1 aSchalk, Gerwin1 aStokes, Bradford, T.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1603389902685nas a2200433 4500008004100000022001400041245011000055210006900165260001200234300001600246490000700262520140200269653003101671653000801702653001601710653002901726653000801755653000801763653002801771653003601799653001401835653000901849653001901858653003201877653002901909100002401938700002601962700001901988700002402007700001902031700002102050700002002071700002002091700002402111700002402135700002302159700002102182856004802203 2004 eng d a0018-929400aThe BCI Competition 2003: progress and perspectives in detection and discrimination of EEG single trials.0 aBCI Competition 2003 progress and perspectives in detection and  c06/2004 a1044–10510 v513 aInterest in developing a new method of man-to-machine communication–a brain-computer interface (BCI)–has grown steadily over the past few decades. BCIs create a new communication channel between the brain and an output device by bypassing conventional motor output pathways of nerves and muscles. These systems use signals recorded from the scalp, the surface of the cortex, or from inside the brain to enable users to control a variety of applications including simple word-processing software and orthotics. BCI technology could therefore provide a new communication and control option for individuals who cannot otherwise express their wishes to the outside world. Signal processing and classification methods are essential tools in the development of improved BCI technology. We organized the BCI Competition 2003 to evaluate the current state of the art of these tools. Four laboratories well versed in EEG-based BCI research provided six data sets in a documented format. We made these data sets (i.e., labeled training sets and unlabeled test sets) and their descriptions available on the Internet. The goal in the competition was to maximize the performance measure for the test labels. Researchers worldwide tested their algorithms and competed for the best classification results. This paper describes the six data sets and the results and function of the most successful algorithms.10aaugmentative communication10aBCI10abeta-rhythm10abrain-computer interface10aEEG10aERP10aimagined hand movements10alateralized readiness potential10amu-rhythm10aP30010aRehabilitation10asingle-trial classification10aslow cortical potentials1 aBlankertz, Benjamin1 aMüller, Klaus-Robert1 aCurio, Gabriel1 aVaughan, Theresa, M1 aSchalk, Gerwin1 aWolpaw, Jonathan1 aSchlögl, Alois1 aNeuper, Christa1 aPfurtscheller, Gert1 aHinterberger, Thilo1 aSchröder, Michael1 aBirbaumer, Niels uhttp://www.ncbi.nlm.nih.gov/pubmed/1518887602522nas a2200277 4500008004100000022001400041245008500055210006900140260001200209300001400221490000700235520169700242653003101939653002701970653001601997653001302013653001402026653002502040653001502065653001902080653002402099100002602123700002602149700002102175856004802196 2003 eng d a0301-051100aBrain-computer interface (BCI) operation: optimizing information transfer rates.0 aBraincomputer interface BCI operation optimizing information tra c07/2003 a237–2510 v633 aPeople can learn to control mu (8-12 Hz) or beta (18-25 Hz) rhythm amplitude in the EEG recorded over sensorimotor cortex and use it to move a cursor to a target on a video screen. In the present version of the cursor movement task, vertical cursor movement is a linear function of mu or beta rhythm amplitude. At the same time the cursor moves horizontally from left to right at a fixed rate. A target occupies 50% (2-target task) to 20% (5-target task) of the right edge of the screen. The user's task is to move the cursor vertically so that it hits the target when it reaches the right edge. The goal of the present study was to optimize system performance. To accomplish this, we evaluated the impact on system performance of number of targets (i.e. 2-5) and trial duration (i.e. horizontal movement time from 1 to 4 s). Performance was measured as accuracy (percent of targets selected correctly) and also as bit rate (bits/min) (which incorporates, in addition to accuracy, speed and the number of possible targets). Accuracy declined as target number increased. At the same time, for six of eight users, four targets yielded the maximum bit rate. Accuracy increased as movement time increased. At the same time, the movement time with the highest bit rate varied across users from 2 to 4 s. These results indicate that task parameters such as target number and trial duration can markedly affect system performance. They also indicate that optimal parameter values vary across users. Selection of parameters suited both to the specific user and the requirements of the specific application is likely to be a key factor in maximizing the success of EEG-based communication and control.10aaugmentative communication10aElectroencephalography10ainformation10aLearning10amu rhythm10aoperant conditioning10aprosthesis10aRehabilitation10asensorimotor cortex1 aMcFarland, Dennis, J.1 aSarnacki, William, A.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1285316902907nas a2200325 4500008004100000022001400041245008700055210006900142260001200211300001300223490000700236520189600243653003102139653003502170653003302205653001902238100002402257700002702281700002302308700002302331700002202354700002202376700002002398700002202418700002102440700002102461700003002482700002102512856004802533 2003 eng d a1534-432000aBrain-computer interface technology: a review of the Second International Meeting.0 aBraincomputer interface technology a review of the Second Intern c06/2003 a94–1090 v113 aThis paper summarizes the Brain-Computer Interfaces for Communication and Control, The Second International Meeting, held in Rensselaerville, NY, in June 2002. Sponsored by the National Institutes of Health and organized by the Wadsworth Center of the New York State Department of Health, the meeting addressed current work and future plans in brain-computer interface (BCI) research. Ninety-two researchers representing 38 different research groups from the United States, Canada, Europe, and China participated. The BCIs discussed at the meeting use electroencephalographic activity recorded from the scalp or single-neuron activity recorded within cortex to control cursor movement, select letters or icons, or operate neuroprostheses. The central element in each BCI is a translation algorithm that converts electrophysiological input from the user into output that controls external devices. BCI operation depends on effective interaction between two adaptive controllers, the user who encodes his or her commands in the electrophysiological input provided to the BCI, and the BCI that recognizes the commands contained in the input and expresses them in device control. Current BCIs have maximum information transfer rates of up to 25 b/min. Achievement of greater speed and accuracy requires improvements in signal acquisition and processing, in translation algorithms, and in user training. These improvements depend on interdisciplinary cooperation among neuroscientists, engineers, computer programmers, psychologists, and rehabilitation specialists, and on adoption and widespread application of objective criteria for evaluating alternative methods. The practical use of BCI technology will be determined by the development of appropriate applications and identification of appropriate user groups, and will require careful attention to the needs and desires of individual users.10aaugmentative communication10aBrain-computer interface (BCI)10aelectroencephalography (EEG)10aRehabilitation1 aVaughan, Theresa, M1 aHeetderks, William, J.1 aTrejo, Leonard, J.1 aRymer, William, Z.1 aWeinrich, Michael1 aMoore, Melody, M.1 aKübler, Andrea1 aDobkin, Bruce, H.1 aBirbaumer, Niels1 aDonchin, Emanuel1 aWolpaw, Elizabeth, Winter1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1289924701629nas a2200265 4500008004100000022001400041245010300055210006900158260001200227300001200239490000800251520078600259653003101045653002901076653002801105653002701133653002401160653002001184653001901204100001901223700002601242700002601268700002101294856004801315 2003 eng d a0304-394000aElectroencephalographic(EEG)-based communication: EEG control versus system performance in humans.0 aElectroencephalographicEEGbased communication EEG control versus c07/2002 a89–920 v3453 aPeople can learn to control electroencephalographic (EEG) sensorimotor rhythm amplitude so as to move a cursor to select among choices on a computer screen. We explored the dependence of system performance on EEG control. Users moved the cursor to reach a target at one of four possible locations. EEG control was measured as the correlation (r(2)) between rhythm amplitude and target location. Performance was measured as accuracy (% of targets hit) and as information transfer rate (bits/trial). The relationship between EEG control and accuracy can be approximated by a linear function that is constant for all users. The results facilitate offline predictions of the effects on performance of using different EEG features or combinations of features to control cursor movement.10aaugmentative communication10abrain-computer interface10abrain-machine interface10aElectroencephalography10amu and beta rhythms10aneuroprosthesis10aRehabilitation1 aSheikh, Hesham1 aMcFarland, Dennis, J.1 aSarnacki, William, A.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1282117802517nas a2200241 4500008004100000022001400041245007400055210006900129260001200198300001600210490000800226520179400234653001302028653002902041653002502070653001902095653001902114100002302133700002602156700002402182700002102206856004802227 2003 eng d a1388-245700aEMG contamination of EEG: spectral and topographical characteristics.0 aEMG contamination of EEG spectral and topographical characterist c09/2003 a1580–15930 v1143 aOBJECTIVE: Electromyogram (EMG) contamination is often a problem in electroencephalogram (EEG) recording, particularly, for those applications such as EEG-based brain-computer interfaces that rely on automated measurements of EEG features. As an essential prelude to developing methods for recognizing and eliminating EMG contamination of EEG, this study defines the spectral and topographical characteristics of frontalis and temporalis muscle EMG over the entire scalp. It describes both average data and the range of individual differences. METHODS: In 25 healthy adults, signals from 64 scalp and 4 facial locations were recorded during relaxation and during defined (15, 30, or 70% of maximum) contractions of frontalis or temporalis muscles. RESULTS: In the average data, EMG had a broad frequency distribution from 0 to >200 Hz. Amplitude was greatest at 20-30 Hz frontally and 40-80 Hz temporally. Temporalis spectra also showed a smaller peak around 20 Hz. These spectral components attenuated and broadened centrally. Even with weak (15%) contraction, EMG was detectable (P<0.001) near the vertex at frequencies >12 Hz in the average data and >8 Hz in some individuals. CONCLUSIONS: Frontalis or temporalis muscle EMG recorded from the scalp has spectral and topographical features that vary substantially across individuals. EMG spectra often have peaks in the beta frequency range that resemble EEG beta peaks. SIGNIFICANCE: While EMG contamination is greatest at the periphery of the scalp near the active muscles, even weak contractions can produce EMG that obscures or mimics EEG alpha, mu, or beta rhythms over the entire scalp. Recognition and elimination of this contamination is likely to require recording from an appropriate set of peripheral scalp locations.10aartifact10abrain-computer interface10aelectroencephalogram10aelectromyogram10aRehabilitation1 aGoncharova, I., I.1 aMcFarland, Dennis, J.1 aVaughan, Theresa, M1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/1294878703278nas a2200229 4500008004100000022001400041245006900055210006700124260001200191300001400203490000700217520263700224653001302861653001702874653001302891653001102904653001902915653002302934100002102957700002202978856004803000 2001 eng d a0147-006X00aActivity-dependent spinal cord plasticity in health and disease.0 aActivitydependent spinal cord plasticity in health and disease c03/2001 a807–8430 v243 aActivity-dependent plasticity occurs in the spinal cord throughout life. Driven by input from the periphery and the brain, this plasticity plays an important role in the acquisition and maintenance of motor skills and in the effects of spinal cord injury and other central nervous system disorders. The responses of the isolated spinal cord to sensory input display sensitization, long-term potentiation, and related phenomena that contribute to chronic pain syndromes; they can also be modified by both classical and operant conditioning protocols. In animals with transected spinal cords and in humans with spinal cord injuries, treadmill training gradually modifies the spinal cord so as to improve performance. These adaptations by the isolated spinal cord are specific to the training regimen and underlie new approaches to restoring function after spinal cord injury. Descending inputs from the brain that occur during normal development, as a result of supraspinal trauma, and during skill acquisition change the spinal cord. The early development of adult spinal cord reflex patterns is driven by descending activity; disorders that disrupt descending activity later in life gradually change spinal cord reflexes. Athletic training, such as that undertaken by ballet dancers, is associated with gradual alterations in spinal reflexes that appear to contribute to skill acquisition. Operant conditioning protocols in animals and humans can produce comparable reflex changes and are associated with functional and structural plasticity in the spinal cord, including changes in motoneuron firing threshold and axonal conduction velocity, and in synaptic terminals on motoneurons. The corticospinal tract has a key role in producing this plasticity. Behavioral changes produced by practice or injury reflect the combination of plasticity at multiple spinal cord and supraspinal sites. Plasticity at multiple sites is both necessary-to insure continued performance of previously acquired behaviors-and inevitable-due to the ubiquity of the capacity for activity-dependent plasticity in the central nervous system. Appropriate induction and guidance of activity-dependent plasticity in the spinal cord is an essential component of new therapeutic approaches aimed at maximizing function after spinal cord injury or restoring function to a newly regenerated spinal cord. Because plasticity in the spinal cord contributes to skill acquisition and because the spinal cord is relatively simple and accessible, this plasticity is a logical and practical starting point for studying the acquisition and maintenance of skilled behaviors.10abehavior10aconditioning10aLearning10aMemory10aRehabilitation10aspinal cord injury1 aWolpaw, Jonathan1 aTennissen, A., M. uhttp://www.ncbi.nlm.nih.gov/pubmed/1152091901315nas a2200289 4500008004100000022001400041245006100055210005800116260001200174300001600186490000800202520045900210653003100669653002900700653002700729653002000756653002900776653002800805653001400833653001900847653002400866100001900890700002100909700002600930700002100956856004800977 2000 eng d a1388-245700aEEG-based communication: presence of an error potential.0 aEEGbased communication presence of an error potential c12/2000 a2138–21440 v1113 aEEG-based communication could be a valuable new augmentative communication technology for those with severe motor disabilities. Like all communication methods, it faces the problem of errors in transmission. In the Wadsworth EEG-based brain-computer interface (BCI) system, subjects learn to use mu or beta rhythm amplitude to move a cursor to targets on a computer screen. While cursor movement is highly accurate in trained subjects, it is not perfect.10aaugmentative communication10abrain-computer interface10aElectroencephalography10aerror potential10aerror related negativity10aevent related potential10amu rhythm10aRehabilitation10asensorimotor cortex1 aSchalk, Gerwin1 aWolpaw, Jonathan1 aMcFarland, Dennis, J.1 aPfurtscheller, G uhttp://www.ncbi.nlm.nih.gov/pubmed/1109076302088nas a2200265 4500008004100000022001400041245006600055210006300121260001200184300001400196490000800210520131500218653003101533653001701564653002701581653002101608653001401629653001901643653002401662100002401686700001801710700002601728700002101754856004701775 1998 eng d a0013-469400aEEG-based communication: analysis of concurrent EMG activity.0 aEEGbased communication analysis of concurrent EMG activity c12/1998 a428–4330 v1073 aOBJECTIVE: Recent studies indicate that people can learn to control the amplitude of mu or beta rhythms in the EEG recorded from the scalp over sensorimotor cortex and can use that control to move a cursor to targets on the computer screen. While subjects do not move during performance, it is possible that inapparent or unconscious muscle contractions contribute to the changes in the mu and beta rhythm activity responsible for cursor movement. We evaluated this possibility. METHODS: EMG was recorded from 10 distal limb muscle groups while five trained subjects used mu or beta rhythms to move a cursor to targets at the bottom or top edge of a computer screen. RESULTS: EMG activity was very low during performance, averaging 4.0+/-4.4% (SD) of maximum voluntary contraction. Most important, the correlation, measured as r2, between target position and EMG activity averaged only 0.01+/-0.02, much lower than the correlation between target position and the EEG activity that controlled cursor movement, which averaged 0.39+/-0.18. CONCLUSIONS: These results strongly support the conclusion that EEG-based cursor control does no depend on concurrent muscle activity. EEG-based communication and control might provide a new augmentative communication option for those with severe motor disabilities.10aaugmentative communication10aconditioning10aElectroencephalography10aElectromyography10amu rhythm10aRehabilitation10asensorimotor cortex1 aVaughan, Theresa, M1 aMiner, L., A.1 aMcFarland, Dennis, J.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/992208902193nas a2200265 4500008004100000022001400041245005800055210005600113260001200169300001400181490000800195520144100203653002801644653002701672653001401699653002501713653001501738653001901753653002401772100002601796700001901822700001801841700002101859856004701880 1997 eng d a0013-469400aSpatial filter selection for EEG-based communication.0 aSpatial filter selection for EEGbased communication c09/1997 a386–3940 v1033 aIndividuals can learn to control the amplitude of mu-rhythm activity in the EEG recorded over sensorimotor cortex and use it to move a cursor to a target on a video screen. The speed and accuracy of cursor movement depend on the consistency of the control signal and on the signal-to-noise ratio achieved by the spatial and temporal filtering methods that extract the activity prior to its translation into cursor movement. The present study compared alternative spatial filtering methods. Sixty-four channel EEG data collected while well-trained subjects were moving the cursor to targets at the top or bottom edge of a video screen were analyzed offline by four different spatial filters, namely a standard ear-reference, a common average reference (CAR), a small Laplacian (3 cm to set of surrounding electrodes) and a large Laplacian (6 cm to set of surrounding electrodes). The CAR and large Laplacian methods proved best able to distinguish between top and bottom targets. They were significantly superior to the ear-reference method. The difference in performance between the large Laplacian and small Laplacian methods presumably indicated that the former was better matched to the topographical extent of the EEG control signal. The results as a whole demonstrate the importance of proper spatial filter selection for maximizing the signal-to-noise ratio and thereby improving the speed and accuracy of EEG-based communication.10aassistive communication10aElectroencephalography10amu rhythm10aoperant conditioning10aprosthesis10aRehabilitation10asensorimotor cortex1 aMcFarland, Dennis, J.1 aMcCane, L., M.1 aDavid, S., V.1 aWolpaw, Jonathan uhttp://www.ncbi.nlm.nih.gov/pubmed/930528702490nas a2200265 4500008004100000022001400041245004000055210003800095260001200133300001400145490000700159520177200166653002801938653002701966653001401993653002502007653001502032653001902047653002402066100002102090700001902111700002102130700002602151856004702177 1997 eng d a0736-025800aTiming of EEG-based cursor control.0 aTiming of EEGbased cursor control c11/1997 a529–5380 v143 aRecent studies show that humans can learn to control the amplitude of electroencephalography (EEG) activity in specific frequency bands over sensorimotor cortex and use it to move a cursor to a target on a computer screen. EEG-based communication could be a valuable new communication and control option for those with severe motor disabilities. Realization of this potential requires detailed knowledge of the characteristic features of EEG control. This study examined the course of EEG control after presentation of a target. At the beginning of each trial, a target appeared at the top or bottom edge of the subject's video screen and 1 sec later a cursor began to move vertically as a function of EEG amplitude in a specific frequency band. In well-trained subjects, this amplitude was high at the time the target appeared and then either remained high (i.e., for a top target) or fell rapidly (i.e., for a bottom target). Target-specific EEG amplitude control began 0.5 sec after the target appeared and appeared to wax and wane with a period of approximately 1 sec until the cursor reached the target (i.e., a hit) or the opposite edge of the screen (i.e., a miss). Accuracy was 90% or greater for each subject. Top-target errors usually occurred later in the trial because of failure to reach and/or maintain sufficiently high amplitude, whereas bottom-target errors usually occurred immediately because of failure to reduce an initially high amplitude quickly enough. The results suggest modifications that could improve performance. These include lengthening the intertrial period, shortening the delay between target appearance and cursor movement, and including time within the trial as a variable in the equation that translates EEG into cursor movement.10aassistive communication10aElectroencephalography10amu rhythm10aoperant conditioning10aprosthesis10aRehabilitation10asensorimotor cortex1 aWolpaw, Jonathan1 aFlotzinger, D.1 aPfurtscheller, G1 aMcFarland, Dennis, J. uhttp://www.ncbi.nlm.nih.gov/pubmed/945806001539nas a2200241 4500008004100000022001400041245005700055210005400112260001200166300001400178490000700192520085200199653002801051653002701079653001401106653002501120653001501145653001901160653002401179100002101203700002601224856004701250 1994 eng d a0013-469400aMultichannel EEG-based brain-computer communication.0 aMultichannel EEGbased braincomputer communication c06/1994 a444–4490 v903 aIndividuals who are paralyzed or have other severe movement disorders often need alternative means for communicating with and controlling their environments. In this study, human subjects learned to use two channels of bipolar EEG activity to control 2-dimensional movement of a cursor on a computer screen. Amplitudes of 8-12 Hz activity in the EEG recorded from the scalp across right and left central sulci were determined by fast Fourier transform and combined to control vertical and horizontal cursor movements simultaneously. This independent control of two separate EEG channels cannot be attributed to a non-specific change in brain activity and appeared to be specific to the mu rhythm frequency range. With further development, multichannel EEG-based communication may prove of significant value to those with severe motor disabilities.10aassistive communication10aElectroencephalography10amu rhythm10aoperant conditioning10aprosthesis10aRehabilitation10asensorimotor cortex1 aWolpaw, Jonathan1 aMcFarland, Dennis, J. uhttp://www.ncbi.nlm.nih.gov/pubmed/7515787