We recorded the activity of 132 proximal-arm-related neurons in caudal primary motor cortex (M1) two monkeys while they generated either isometric forces against a rigid handle or arm movements with heavy movable handle, same eight directions horizontal plane. The increased monotonic fashion direction force target. exerted movement task were more complex, including an initial accelerating followed by transient decelerating opposite to as hand approached EMG proximal-arm muscles reflected...

Scott, Stephen H., Lauren E. Sergio, and John F. Kalaska. Reaching movements with similar hand paths but different arm orientations. II. Activity of individual cells in dorsal premotor cortex parietal area 5. J. Neurophysiol. 78: 2413–2426, 1997. Neuronal activity primary motor (MI) is altered when monkeys make reaching along handpaths at shoulder level two orientations, either the natural orientation elbow positioned below or an abducted nearly to level. The present study examines what...

Single-unit recordings in macaque monkeys have identified effector-specific regions posterior parietal cortex (PPC), but functional neuroimaging the human has yielded controversial results. Here we used on-line repetitive transcranial magnetic stimulation (rTMS) to determine saccade and reach specificity PPC. A short train of three TMS pulses (separated by an interval 100 ms) was delivered superior parieto-occipital (SPOC), a region over midposterior intraparietal sulcus (mIPS), site close...

Sergio, Lauren E. and John F. Kalaska. Changes in the temporal pattern of primary motor cortex activity a directional isometric force versus limb movement task. J. Neurophysiol. 80: 1577–1583, 1998. We recorded 75 proximal-arm-related cells caudal (MI) while monkey generated either forces or movements against an inertial load. The were eight directions horizontal plane. at hand increased monotonically direction target level. exerted load task was more complex, including transient...

We report here the activity of 96 cells in primate primary motor cortex (MI) during exertion isometric forces at hand constant spatial directions, while was five to nine different locations on a plane. The discharge nearly all varied significantly with both location and direction force before force-ramp generation as well static force-hold. In addition, displayed changes variation their locations. This change relationship often expressed part cell's directional tuning Cell tended shift...

To provide incidence rates and days to symptom resolution cognitive recovery stratified by sex sport at a Canadian institution.A retrospective chart analysis.Seven hundred fifty-nine varsity level athletes competing in men's football, women's soccer, volleyball, basketball, ice hockey, field rugby, tennis, water polo, swimming, badminton, cross-country, track the 2008 2009 season through 2010 2011 season.Incidence of concussion, recovery, as measured clinical interpretation using sports...

The ability to perform visually-guided motor tasks requires the transformation of visual information into programmed outputs. When guiding does not align spatially with output, brain processes rules integrate for an appropriate response. Here, we look at how performance on such is affected in young adult athletes concussion history.Participants displaced a cursor from central peripheral targets vertical display by sliding their finger along touch sensitive screen one two spatial planes....

Cognition allows for the use of different rule-based sensorimotor strategies, but neural underpinnings such strategies are poorly understood. The purpose this study was to compare activity in superior parietal lobule during a standard (direct interaction) reaching task, with two nonstandard (gaze and reach spatially incongruent) tasks requiring integration information. Specifically, these involved dissociating planes vision or rotating visual feedback by 180°. Single unit activity, gaze,...

Recent evidence suggests that visuomotor behaviors may be disrupted in the very early stages of Alzheimer's disease (AD). Here we propose using kinematic measures under conditions place demands on visual-spatial and cognitive-motor processing provide an effective behavioral means to detect subtle changes associated with AD risk.To this end, have tested 22 young adults (mean age = 26.4 ± 4.1) older 64.3 10.1) at low AD, 67.7 11.3) high risk (i.e., strong family history or diagnosis mild...

Sergio, Lauren E. and John F. Kalaska. Systematic changes in directional tuning of motor cortex cell activity with hand location the workspace during generation static isometric forces constant spatial directions. J. Neurophysiol. 78: 1170–1174, 1997. We examined 46 proximal-arm-related cells primary (MI) a task which monkey uses arm to exert at directions while is one nine different locations on plane. The discharge rate all was significantly affected by both direction force final...

<i>Background/Aims:</i> This study examined cognitive-motor integration in adults with mild cognitive impairment (MCI). Previously, we showed that the performance of early-stage Alzheimer’s disease patients declined significantly as a visually-guided movement went from having standard mapping (vision and action spatially aligned) to non-standard incongruent). The present extends this line research by examining individuals affected MCI. <i>Methods:</i> participants...

We investigated whether children and adolescents with concussion history show cognitive-motor integration (CMI) deficits.Asymptomatic (n = 50; mean 12.84 years) no 49; mean: 11.63 slid a cursor to targets using their finger on dual-touch-screen laptop; target location motor action were not aligned in the CMI task.Children showed prolonged deficits, that performance did match of controls until nearly 2 years postevent.These deficits may be due disruptions fronto-parietal networks,...

Abstract In the past it has often been assumed that cortical networks for visually guided movement are same males and females. Here we use functional magnetic resonance imaging (fMRI) to show significant sex‐related differences in human brain activity during visual‐to‐motor transformation tasks. Although behavioural performance of male female groups did not differ, levels blood oxygen level‐dependent fMRI apparent several areas have previously demonstrated be important movements. These...

This study examined the ability of neurologically healthy individuals and with Alzheimer's disease (AD) to successfully complete procedures involving short-term spatial visuomotor memory tasks, tasks increasingly complex transformations. Participants made sliding finger movements over a clear touch-sensitive screen on two separate planes (vertical horizontal), visually constant remembered target positions. Significant main effects were observed between participant groups reaction time...

Posterior parietal cortex (PPC) has been implicated in the integration of visual and proprioceptive information for planning action. We previously reported that single-pulse transcranial magnetic stimulation (TMS) over dorsal-lateral PPC perturbs early stages spatial processing memory-guided reaching. However, our data did not distinguish whether TMS disrupted reach goal or internal estimate initial hand position needed to calculate vector. To test between these hypotheses, we investigated...

Patients with optic ataxia (OA), who are missing the caudal portion of their superior parietal lobule (SPL), have difficulty performing visually-guided reaches towards extra-foveal targets. Such gaze and hand decoupling also occurs in commonly performed non-standard visuomotor transformations such as use a computer mouse. In this study, we test two unilateral OA patients conditions 1) change physical location visual stimulus relative to plane limb movement, 2) cue that signals required...

Alzheimer's disease (AD) is typically associated with impairments in memory and other aspects of cognition, while deficits complex movements are commonly observed later the course disease. Recent studies, however, have indicated that sub