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Executive control

Friday, September 30th,   2011 [17:20 - 19:20]

PS_1.032 - Cognitive control in task switching assessed with imperative probes

Sackur, J.

Laboratoire de Sciences Cognitives et Psycholinguistique, École Normale Supérieure, Paris, France

Task switching is one of the major paradigms used to explore the flexibility of executive control of cognition. In the task-cuing procedure, a cue instructs the subject which task is to be performed on a target that affords two possible tasks. Switch costs are obtained by comparing performances in repeated trials versus switch trials. Although this procedure can be refined so as to disentangle effects of cue and task switches, the level at which switches impact performances may still be unclear. Here, I introduce a novel procedure to probe task-set reconfiguration and cognitive control modulation: a third task, based on imperative targets unrelated to the cues is interspersed among traditional task switching trials. This third task enables me to probe modulations of cognitive control irrespective of any performance effects on primary, cue-related targets. Results show that probe trials are slowed after a switch, and that this effect is reduced for long cue-stimulus intervals. This shows that task switching cues induce endogenous adaptations of cognitive control that cannot be explained by stimulus-level factors.

PS_1.033 - Response selection in the premotor cortex: a transcranial magnetic stimulation study

Bardi, L. & Mapelli, D.

Department of General Psychology, University of Padova, Padova, Italy

Response activation and selection in situations of conflict have been shown to recruit a large frontoparietal network. Within this network, a critical role in response selection has been attributed to premotor cortex. We applied single-pulse TMS over left and right premotor cortex (PM) at different timing after stimulus onset (SOAs) while participants were performing a spatial conflict task (the Simon task). In the Simon task a conflict arises because irrelevant spatial information competes for response selection either facilitating of interfering with performance. Responses are faster when stimulus and response position correspond than when they do not. Results showed that temporary interference with the left PM caused a suppression of the Simon effect due to a delay of corresponding trials in a early timing (160 ms SOA) while an increase of the Simon effect, due to a delay of non-corresponding trials, was observed in a later timing (250 ms SOA). These outcomes suggest that PM plays a critical role both in the activation of the corresponding response and in conflict resolution when the corresponding response has to be overcome. Moreover, our finding extends the idea of the left-hemisphere lateralization of the network for action selection in right-handed subjects.

PS_1.034 - Trait anxiety and attentional networks: An ERP study

Pacheco Unguetti, A. P. , Rueda, M. R. , Castellanos, M. C. , Acosta, A. & Lupiáñez, J.

Department of Experimental Psychology and Behavioural Physiology. University of Granada. Granada, Spain

When studying the functioning of attentional networks (orienting, alerting, and executive control) in individuals with different type and level of anxiety, we have previously observed poorer efficiency of the executive attention network in high trait-anxiety individuals as well as an overfunctioning of the alerting and orienting networks associated with state-anxiety compared to age matched controls. In the current study we aim at examining brain activation during performance of a modified version of the Attention Network Test as a function of trait-anxiety using a high-density event-related potentials technique. Participants (n=50) are individuals with high and low STAI trait-anxiety scores. Preliminary data show the most important difference between High and Low anxiety on the flanker interference effect, an index of efficiency of the executive control network. High anxiety participants show a delayed N2b effect (i.e. larger negative amplitude for incongruent compared to congruent trials) over fronto-parietal channels compared to the Low-anxiety group. Additionally, the N2b is left-lateralized for the High-anxiety group and right-lateralized for the Low-anxiety group. Further, the fronto-central P3 effect appears to be larger for the high-anxiety group. These results are consistent with the idea that anxious individuals have poorer efficiency of regulatory mechanisms important for attentional control.

PS_1.035 - On the origin of task confusions in task switching

Steinhauser, M.

Department of Psychology, University of Konstanz, Konstanz, Germany

When participants rapidly switch between tasks that share the same stimuli and responses, task confusions can occur. The present study investigated whether these task confusions result from failures of endogenous control (i.e., task preparation) or from failures of exogenous control (i.e., stimulus-induced task conflicts). In a series of task-switching experiments, the frequency of task confusions was estimated by considering distractor errors which result when participants erroneously respond to a distractor stimulus associated with the alternative task. The efficiency of exogenous control was manipulated by varying the temporal order of target and distractor presentation. The efficiency of endogenous control was manipulated by varying the time available for preparing the task in advance. The data show that only the efficiency of exogenous control but not the efficiency of endogenous control influenced the proportion of distractor errors. This suggests that task confusions are more related to failures in exogenous control.

PS_1.036 - Task switching with a 2:1 cue-to-task mapping: Separating cue disambiguation from task-rule retrieval

Kleinsorge, T.

Leibniz Research Centre for Working Environment and Human Factors

An study is reported that investigated switching among two numerical judgment tasks with a factorial variation of the cue-to-task mapping (1:1 versus 2:1) for each of the tasks. In addition, the precuing interval (CSI) was varied. The results suggest that with a long CSI of 1,100 ms, switching performance is almost completely determined by the task-specific conditional probability of a task switch given a cue switch. This effect probably reflects the complexity of task-rule retrieval. Without preparation (CSI = 0 ms), the complexity of cue disambiguation as a function of the number of cues across tasks seems to account for most part of the additional variance observed in this condition. The latter observation is in line with suggestions that increasing the number of cues per task from one to two introduces additional demands on the level of cue processing that reflect the transition from an isomorphic to a homomorphic mapping function.

PS_1.037 - Retrieval-induced forgetting depending on an affective regulation of attentional control

KolaƄczyk, A. , Reszko, M. & Mordasiewicz, P.

Warsaw School of Social Sciences and Humanities Faculty in Sopot

The retrieval-induced forgetting (RIF) depends on WM. RIF has been observed only in telic memorization. Pursuing a goal, which in this case is “remember”, requires attentional control, which flexibly adjusts mental operations to situational requirements (e.g. unrelated distracters or even related tasks as retrieval practice). If WM is overloaded, attention controls only current task, not the main goal. The present studies verify the hypothesis that valuations direct attention toward goal-relevant, important objects, and devaluations divert attention from unimportant, “rubbish” objects. RIF could be the result of devaluation (inhibition) of non-practiced words from practiced category (Rp-) or of a valuation (positive valuation &control) of non-practiced category (NRP). Individual differences in attentional control are the hypothetical moderator of RIF and goal-relevant evaluations. Therefore, stronger attentional control should produce more pronounced valuations, devaluations and RIF. The Attentional Control Scale and the affective priming task (for implicit evaluations) were introduced to RIF paradigm. The three experiments employing different amount of presented material and different number of retrieval trials, show that implicitly measured affect reflects goal orientation only in subjects who score high on Attentional Control Scale. RIF could be the result of NRP control (valuation), not only RP- inhibition.

PS_1.038 - Do acute bouts of pyhsical exercise prior to cognitive control training enhance training effects?

Zinke, K. , Einert, M. , Pfennig, L. & Kliegel, M.

Department of Psychology. Technische Universität Dresden. Dresden, Germany.

Cognitive training can enhance performance in executive control tasks. Performance in these tasks has also been shown to be influenced by short bouts of physical exercise. Current study was designed to explore whether acute bouts of exercise (cycling on a stationary bike) directly prior to cognitive training (practicing task switching) can enhance training effects. For that purpose, a group of adolescents (10-14 years) that received a three-week cognitive training was compared to a group that received the same cognitive training but who exercised before each training session. Additionally, a no-contact and an exercise-only control group were included. All groups comprised 20 participants that were matched in age, gender, and basic cognitive functioning. Analyses indicated that both training groups significantly reduced their switching costs over the course of the training sessions and also reduced their mixing costs in a near transfer task more than the non-trained control groups. Interestingly, there was tendency for the exercise-and-cognitive-training group to commit fewer errors during training compared to the cognitive-training-only group. These findings indicate that cognitive control can be enhanced in adolescents through training and prior exercise may influence some aspects of these training effects.

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