Reward‐related activity in the human motor cortex

Abstract

The human primary motor cortex (M1) participates in motor learning and response selection, functions that rely on feedback on the success of behavior (i.e. reward). To investigate the possibility that behavioral contingencies alter M1 activity in humans, we tested intracortical inhibition with single and paired (subthreshold/suprathreshold) transcranial magnetic stimulation during a slot machine simulation that delivered variable money rewards for three-way matches and required no movement. A two-way match before the third barrel had stopped (increased reward expectation) was associated with more paired-pulse inhibition than no match. Receiving a large reward on the preceding trial augmented this effect. A control task that manipulated attention to the same stimuli produced no changes in excitability. The origin of this reward-related activity is not clear, although dopaminergic ventral tegmental area neurons project to M1, where they are thought to inhibit output neurons and could be the source of the finding. Transcranial magnetic stimulation of M1 may be useful as a quantitative measure of reward-related activity.

Counterfactual thinking affects the excitability of the motor cortex

“…In the study of Kapogiannis et al (2008) it was shown that M1 excitability might be modulated by an upcoming potential reward. However, that study examined only the effect of passive viewing of a monetary gain.…”

“…Some studies have focused on the anticipatory processing of upcoming potential rewards that occurs immediately before and during the selection of an appropriate action aimed at getting the rewards (Klein-Flü gge & Bestmann, 2012; Freeman, Razhas, & Aron, 2014; Gupta & Aron, 2011) or even in the absence of any motor requirement (e.g., slot machine paradigm; Kapogiannis, Campion, Grafman, & Wassermann, 2008). Other studies have explored the effect of seeing pictures of coins relative to abstract symbols presented soon after the execution of an action (Suzuki et al, 2014;Thabit et al, 2011).…”

Motor cortex inhibition

“…For example, a recently published, small study in healthy adults showed that SICI is reduced when an individual is attending to a task and then increases in response to anticipation of reward during this task. 26 This finding suggests that mechanisms measured by SICI may engage in attention and reward processing. Such studies in ADHD in children might further enhance our understanding of SICI as a quantitative, biologically based marker of ADHD symptoms.…”

“…Studies of SICI in healthy adults suggest that this may be relevant to motor task inhibition 25 and reward expectation. 26 Difficulties with response selection and control (including increased inhibitory failure and variability) are hallmarks of ADHD, 27 as are alterations in reward motivation. 28 Refinement of neural signals critical to developing appropriate response selection and control, particularly in response to reward, may be critical to development of appropriate control of impulsive, hyperactive, and off-task behavior.…”

Robotic Technology for Spinal Cord Injury: Upper Extremity

“…Ödüllendirme motor hafızanın uzun sürmesine karşın cezalandırma ile kısa sürdüğü görülüyor. Bu nedenle doğru hareket sekansları için sanal gerçeklik ile ödül sinyallerinin eşleştirildiği stratejiler klinik fayda sağlayabilirler (3,21,22).…”