| Popis: |
Background: The efference copy (EC)/corollary discharge (CD) mechanism of predictive coding has been hypothesized to function as a neural indicator of self-generation of action. According to this hypothesis, performing an action generates a copy of the motor command (the EC), which results in a CD (representing the sensory consequences expected from performing that action). As a result, activity in the sensory cortex related to the sensory consequences of performing the action is suppressed. This mechanism has been shown to be dysfunctional in individuals with schizophrenia (SZ). There is some evidence that this mechanism is conserved even when the action and sensory consequence are not mechanically coupled (ie, an EC and CD are generated in response to pushing a button to hear a tone, respectively). This suggests that information related to self-initiation in addition to self-generation of action may be carried by the EC. To further explore this phenomenon, we investigated the strength of the CD in SZ and controls (CN) in response to cued action across conditions requiring different degrees of cognitive control. We hypothesized that increased cognitive control would recruit increased intentionality (ie, greater degree of self-initiation) of motor actions, possibly resulting in a more robust CD compared to a simple reaction time task, wherein intention to move is largely offloaded onto the appearance of the stimulus cuing action. |
