Mechanisms of Impulsive Responding to Temporally Predictable Events as Revealed by Electromyography. (21st January 2020)

• Record Type: Journal Article
• Authors: Korolczuk, Inga; Burle, Boris; Coull, Jennifer T.; Smigasiewicz, Kamila
• Is Part Of: Neuroscience. Volume 428(2020)
• Page Start: 13
• Page End: 22
• Publication Date: 2020-01-21
• Subjects: CAF Conditional Accuracy Function -- CR correction ratio -- CT correction time -- EMG electromyography -- FP foreperiod -- PE partial error; temporal prediction -- timing -- motor control -- response inhibition -- EMG; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2019.12.022
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: Temporal predictability often benefits behaviour but can induce impulsive responding. Erroneous but subthreshold EMG activations can be used to index impulsive behaviour. Temporal cueing increased the number and speed of such impulsive responses. Yet temporal cueing did not impair the ability to then correct these responses. Motor impulsivity can explain both costs and benefits of temporal predictability. Abstract: Temporal predictability optimises behaviour when a simple response is required, as demonstrated by faster reaction times (RTs) and higher accuracy. However, its beneficial effects come at a cost under situations of response conflict. Here, we investigated the motor underpinnings of behaviour to temporally predictable events in the Simon conflict task. We compared motor responses to lateralised targets whose position conflicted (incompatible condition) or not (compatible condition) with the hand of response. Importantly, electromyographic (EMG) recordings allowed us to study "partial errors", defined as subthreshold muscle activity in the incorrect response agonist preceding a correct response. Advanced distributional analyses coupled with EMG data revealed that temporal predictability induced impulsive premature responding, as indexed by increased likelihood of fast incorrect EMG activations (both partial errors and errors) to incompatible targets. In parallel, responding to temporally predictable targets speeded the latency of partial errors, further indicating that temporal predictability increased the tendency to act prematurely. There was, however, no effect of temporal predictability on subsequent suppression of partial errors. Our results provide direct evidence that temporal predictability acts by increasing the urge to initiate a fast, yet potentially erroneous, response. This mechanism parsimoniously explains both beneficial effects of temporal predictability when no conflict in the environment is present, as well as its costs when more complex motor behaviour is required.