How to stop and change a response: The role of goal activation in multitasking.

Abstract

Multitasking was studied in the stop-change paradigm, in which the response for a primary GO1 task had to be stopped and replaced by a response for a secondary GO2 task on some trials. In 2 experiments, the delay between the stop signal and the change signal was manipulated to determine which task goals (GO1, GO2, or STOP) were involved in performance and to determine whether the goals were activated in series or in parallel. As the delay increased, the probability of responding on stop trials changed very little, but GO2 task reaction times decreased substantially. Such effects are consistent with both a nondeterministic serial model (in which the GO1 goal is replaced by the STOP goal, which is subsequently replaced by the GO2 goal) and a limited-capacity parallel model (in which stopping and GO2 processing occur concurrently) with a capacity-sharing proportion that resembles serial processing.

How to withhold or replace a prepotent response: An analysis of the underlying control processes and their temporal dynamics

“…The strong similarities between the change-signal and withhold-signal trials are consistent with the idea that a stop process or goal is needed to quickly change a response (Verbruggen et al, 2008;Camalier et al, 2007). Furthermore, the results are in line with recent theoretical accounts and fMRI findings (e.g., Band et al, 2003;Mars et al, 2007;Kenner et al, 2010;Boecker et al, 2011), suggesting the same inhibitory mechanisms are at play when subjects have to cancel or replace a response.…”

“…For example, Verbruggen, Schneider and Logan (2008) introduced in a stop-change paradigm a delay between the stop signal and the go2 signal to examine whether the go1 response can be inhibited simply by activating the go2 response (go1ç go2) or whether it also requires a top-down inhibition process (go1ç stop + go2). The results of two experiments were consistent with models that included a stop process.…”

Control in Response Inhibition

“…Stop and go processes do not seem to share capacity in this way (e.g., Logan, 1981;Logan & Burkell, 1986;Verbruggen, Schneider, & Logan, 2008). Yamaguchi, Logan, and Bissett (2012) measured SSRT in a dual-task experiment in which subjects had to stop one of two go tasks.…”

A causal role of the right inferior frontal cortex in implementing strategies for multi-component behaviour

“…Such coordination requires the organization of individual actions into a hierarchical structure that can be flexibly interrupted and altered to achieve a goal whenever necessary. A number of previous studies have demonstrated that people apply different strategies when coordinating complex motor plans [1][2][3] in situations requiring a chaining of different actions to achieve a goal; however, the neuronal mechanisms underlying the strategy that links individual actions in multi-component behaviour have remained elusive.…”

“…However, an alternative strategy in which different task goals are activated with some temporal overlap (that is, parallel processing) hampers the efficient unfolding of multi-component behaviour, possibly because different actions interfere with each other and overstrain response selection capacities [1][2][3][4] .…”