Age and cognitive control preservation modulate the neuronal markers of task switching

The study was carried out with the objective of exploring the joint influence of age and cognitive control on the behavioral and electrophysiological indicators connected to the change of task in different sample types.

Thus, the sample was divided into two groups of people of middle age (49-60 years) and older (61-80 years), according to the general score in a composite of six neuropsychological measures of executive function. All participants made a version of the Wisconsin card grading test adapted to measure event-related potentials. The results obtained from the brain responses at sensory and motor level were diverse. First, we could see how working memory was conserved in both older adults and middle-aged adults.

In addition, it could be seen how in adults with low executive control, the costs of reactivating the task were greater and the capacity to prepare for the task when there if interference and distractions was less. In middle-aged adults, it was found a higher cost to perform alternating tasks, which was associated with the presence of more slow fronto central negativities, suggesting an inefficient maintenance of the information of task over time. In contrast, the brain responses in older adults showed an anterioritzation (change of topology towards frontal regions) of the P300 potential activity associated with the change of task. As well, an attenuation of fronto central negativities was observed during the realization of a single task, without alternation.

Finally, the association that found between age and cognitive control by the different indexes of task change costs suggests a differential influence of the two stages of information processing: preparation to carry put the task and maintain it in the time. To the contrary, the effects related to age have a more noticeable influence on the neural indices responsible for the selection of the response and the execution of the task.

 

Reference: Adrover-Roig D, & Barceló F. (2010). Individual differences in aging and cognitive control modulate the neural indexes of context updating and maintenance during task switching. Cortex; 46(4):434-50