bioRxiv Science⌕ Search

Biology subjects

Greenlee, J.

Publications and source records attributed to Greenlee, J..

2 recordsLinked to original sources

A domain-general basal ganglia mechanism for inhibitory control during language comprehension

Whether controlled language processing involves domain-general or language-specific neural circuits is subject of controversial debate. We tested whether the inhibitory control of linguistic activity shares a common neural process with motor inhibition in twenty humans undergoing intra- and extracranial neural field potential recordings and deep-brain stimulation. Engaging motor and linguistic inhibition simultaneously resulted in a significant behavioral cost, suggesting a shared underlying neural process. Indeed, neural decoders trained during motor inhibition were able to decode linguistic inhibition and vice versa. Depth-electrode recordings from the subthalamic nucleus (STN), a key basal ganglia area for inhibitory control, showed increased {beta}-band (13-30 Hz) activity during both linguistic and motor inhibition. Finally, disrupting the STN via deep-brain stimulation impaired behavioral and neural signatures of both linguistic and motor inhibition. Together, these findings show that the inhibitory control of language and movement share a domain-general mechanism implemented via the subthalamic nucleus of the basal ganglia.

neuroscience↗

Cortico-basal ganglia dynamics of global and selective response inhibition in humans

Response inhibition is an important cognitive control mechanism, which enables flexible behavior by stopping inappropriate actions. Intracranial recordings across species have identified a neural circuit that implements response inhibition via the subthalamic nucleus of the basal ganglia. However, this work has been limited to simple tasks, in which unequivocal, salient "stop"-signals require the inhibition of all ongoing responses. Notably, response inhibition in the real world is substantially different. Real-world response inhibition is selective: it occurs only after specific salient signals ( stimulus-selectivity) and stops only specific movements, while others continue ( response-selectivity). If and how the fronto-subthalamic system implements selective inhibition is largely unknown. Here, we recorded subthalamic local field potentials and scalp-EEG in humans performing a novel, selective inhibition task. Salient signals either required stopping all initiated responses (global inhibition), stopping only some responses (response-selective inhibition), or continuing all responses - i.e., ignoring the signal (which ensures stimulus-selectivity). All three signals initially triggered a common fronto-subthalamic inhibitory process, signified by a rapid increase in {beta}-burst activity. During global inhibition, subthalamic {beta}-bursting subsequently increased above baseline, persisting for over a second. During response-selective inhibition, this activity was delayed, which enabled a second bout of disinhibition and allowed appropriate responses to continue. Throughout this period, frontal cortical and subthalamic {beta}-band activity was tightly coupled. This shows that selective inhibition is implemented through rapid, context-dependent engagement and release of fronto-subthalamic inhibition. Moreover, subthalamic activity lasted substantially longer than assumed by classic behavioral-computational models. This supports recent theoretical models that assume protracted response inhibition during action-stopping.

neuroscience↗