Activity of somatosensory responsive neurons in high subdivisions of SI cortex during locomotionстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 13 сентября 2017 г.
Аннотация:Responses of neurons in the primary somatosensory cortex during movements are poorly understood, even during such simple tasks as
walking on a flat surface. In this study,weanalyzed spike discharges of neurons in the rostral bank of the ansate sulcus (areas 1–2) in 2 cats
while the cats walked on a flat surface or on a horizontal ladder, a complex task requiring accurate stepping. All neurons (n82) that had
receptive fields (RFs) on the contralateral forelimb exhibited frequency modulation of their activity that was phase locked to the stride
cycle during simple locomotion. Neurons with proximal RFs (upper arm/shoulder) and pyramidal tract-projecting neurons (PTNs) with
fast-conducting axons tended to fire at peak rates in the middle of the swing phase, whereas neurons with RFs on the distal limb
(wrist/paw) and slow-conducting PTNs typically showed peak firing at the transition between swing and stance phases. Eleven of 12
neurons with tactile RFs on the volar forepaw began firing toward the end of swing, with peak activity occurring at the moment of foot
contact with floor, thereby preceding the evoked sensory volley from touch receptors. Requirement to step accurately on the ladder
affected 91% of the neurons, suggesting their involvement in control of accuracy of stepping. During both tasks, neurons exhibited a wide
variety of spike distributions within the stride cycle, suggesting that, during either simple or ladder locomotion, they represent the cycling
somatosensory events in their activity both predictively before and reflectively after these events take place.