Unravelling Trigger Failures: Towards a cognitive account of response-inhibition problems.

Response inhibition is the ability to stop actions when they are no longer appropriate, and is one of the key cognitive functions that underlie adaptive behavior. Formally, response inhibition is described as a ‘race’ between two responses: a go response that runs to execute the action and a stop response that runs to inhibit it. Older work mostly focused on the question how long it takes to stop a response (i.e., stop-response latency), but it neglected a critical aspect of response inhibition: trigger failures, which are instances in which the stop response was not triggered at all. Although there is now converging evidence that trigger failures are fundamental to response inhibition (and potentially other cognitive functions), there is a gap in our understanding how they come about. In this project, I aim to fill this critical gap. First, I will develop computational methods to estimate trigger failures on a fine-grained level. Second, I will examine the processes that drive trigger failures according to a cognitive-control framework that describes response inhibition as a chain of processes that happen on different time scales. I will examine the basic processes that underlie trigger failures (signal detection and response selection) as well as the elements that modulate these processes (proactive control and mind wandering), using an EEG-pupillometry set-up. Together, this research will uncover the underpinnings of a neglected yet critical part of cognitive control.