John W. Krakauer

This study shows that cervical spinal cord stimulation impairs proprioception but improves voluntary arm reaching in post-stroke patients.

This study investigates whether mechanical reasoning is necessary for novel tool use in apraxia and finds it is not, suggesting tool use is more intuitive.

This study shows that the severity of flexor synergy after stroke in non-human primates depends on the extent of corticofugal disruption, not specific cortical damage.

The paper identifies a spinal origin for the flexor synergy in non-human primates, showing that spinal microstimulation generates coactivation aligned with the post-stroke synergy.

This study re-examines Twitchell's 1951 findings on post-stroke arm function using modern kinematic analysis, showing that synergy intrusion and weakness evolve differently over time.

The paper shows that arm dominance arises from practice with tool use, not innate motor control asymmetry, by analyzing movement trajectory shapes in tool-based and writing tasks.

This study examines arm control recovery after motor cortex and red nucleus lesions in monkeys, finding that damage to specific cortical areas and the rubrospinal tract affects movement speed and recovery differently.

This study finds that reinforcement learning is impaired in the sub-acute post-stroke period, while error-based learning remains unaffected, suggesting the need for adjusted rehabilitation strategies.

This study investigates how continuous motor skills are learned through a video game task, finding that performance generalizes at the kinematic level but not at the task success level, suggesting a flexible control policy rather than chunked action sequences.

This study examines finger individuation impairment after stroke, finding two dissociable factors: loss of control complexity and flexor bias intrusion.

This study examines how weakness and flexor synergy intrusion affect arm movement coordination in sub-acute stroke patients using kinematic analysis and clinical scales.

This study investigates whether control of moving and holding is independently affected in stroke patients, finding functional separation between these modes of control despite shared characteristics in resting biases and movement synergies.

The paper evaluates the proportional recovery rule (PRR) as a model for motor impairment recovery post-stroke, finding support for its biological relevance and introducing statistical methods to assess recovery models.

This study investigates how motor skill acquisition evolves with practice, identifying memory storage and execution optimization as key factors, and shows that noninvasive brain stimulation can improve motor learning in older adults.

The paper investigates how implicit and explicit learning systems compete during sensorimotor adaptation, showing that shared error signals can lead to competition and reduced learning in one system when the other is enhanced.

This study challenges the forward-model-based theory of motor adaptation by showing that implicit adaptation under mirror-reversed feedback follows a pattern consistent with direct policy learning rather than forward-model-based learning.

The paper investigates how arm holding is controlled by showing that postural fields integrate reach commands, even after corticospinal damage.

The paper shows that latent habits can be unmasked by limiting response time, with habit expression peaking 300-600ms after stimulus presentation.

The paper investigates how practice affects memory representation in visuomotor learning by distinguishing between implicit recalibration and deliberate re-aiming.

This study finds no evidence of cortical reorganization after stroke using resting-state fMRI despite behavioral recovery.

This study investigates how humans imitate movements by analyzing stroke patients' ability to replicate trajectories using different cues, finding that dorsal premotor cortex plays a key role in abstract trajectory representation.

This study shows that patients with cerebellar degeneration cannot switch from sensory-prediction-error-based to target-error-based learning in visuomotor tasks, even when vision of the hand eliminates sensory-prediction errors.

The paper shows that cerebellar damage impairs both implicit learning and the ability to develop an aiming strategy in sensorimotor adaptation tasks.

The paper analyzes mirror movements in stroke patients to assess contributions from cortical and subcortical pathways to hand recovery.

This study tracks recovery of hand function after stroke, finding that strength and finger control recover differently, with individuation improving beyond a strength threshold due to CST-dependent mechanisms.