Executive Attentional Resources Research Articles

Closing-in in Parkinson’s disease individuals with dementia: An experimental study

Introduction: The tendency to reproduce figures close to or superimposed on the model in copying tasks, the so-called Closing-in (CI) phenomenon, has been rarely reported in individuals affected by Parkinson’s disease and associated dementia (PD-D). We aimed to comprehend the genesis of CI in PD-D individuals by assessing whether reduction of attention/executive resources can increase the tendency to deviate toward the model. Method: Thirty PD-D individuals underwent a neuropsychological evaluation exploring visuo-spatial, visuo-constructional, executive and memory abilities. An experimental copying task was employed in single and in two dual task conditions to assess whether a (verbal) cognitive load can increase CI in these individuals, compared with a matched sample of healthy adults. Results: CI occurred in 19/30 (63.3%) PD-D individuals: 4 of them produced copies close to the model (near-CI), whereas 15 individuals also superimposed their copies on the model (adherent-CI) besides showing near-CI. Presence of CI in PD-D individuals was significantly correlated with executive dysfunction but not with general cognitive impairment. In the experimental copying task the tendency to deviate toward the model was strongly correlated with executive dysfunction, and significantly increased when PD-D individuals were engaged in dual-task compared with single task conditions. Some individuals attempted to counteract CI, but this trend significantly decreased in dual-task compared with the single task conditions. In healthy adults the drift toward the model was significantly smaller than in PD-D individuals; in dual-task conditions healthy adults only showed a significant decrease in their ability to compensate for this drift. Conclusions: In PD-D individuals the tendency to deviate toward a salient model is strongly enhanced by a concurrent cognitive load. Such preliminary findings would suggest a relationship between reduction of executive attentional resources and the genesis of CI in PD-D individuals.

Executive attentional resources in timing: Effects of inhibitory control and cognitive aging.

This research is based on an executive resource theory of timing, which postulates that time perception relies on specialized attentional resources that support executive cognitive functions. In 4 experiments, older and younger participants performed a timing task and an executive task emphasizing inhibitory control under both single-task and dual-task conditions. The timing task in each experiment was serial temporal production. The executive tasks, representing different types of inhibitory control, were the flanker task (Experiment 1), the number-letter task (Experiment 2), the go/no-go task (Experiment 3), and the antisaccade task (Experiment 4). The results showed (a) a pattern of bidirectional interference in each experiment, in that the concurrent inhibition tasks interfered with timing performance and concurrent timing interfered with inhibition performance, (b) the older participants demonstrated a stronger bidirectional interference effect relative to younger participants in 3 experiments, and (c) weaker versions of the inhibition tasks produced weaker interference effects. These findings support the idea that temporal processing relies on executive attentional resources.

Task instructions and implicit theory of mind

It has been hypothesized that humans are able to track other’s mental states efficiently and without being conscious of doing so using their implicit theory of mind (iToM) system. However, while iToM appears to operate unconsciously recent work suggests it does draw on executive attentional resources (Schneider, Lam, Bayliss, & Dux, 2012) bringing into question whether iToM is engaged efficiently. Here, we examined other aspects relating to automatic processing: The extent to which the operation of iToM is controllable and how it is influenced by behavioral intentions. This was implemented by assessing how task instructions affect eye-movement patterns in a Sally–Anne false-belief task. One group of subjects was given no task instructions (No Instructions), another overtly judged the location of a ball a protagonist interacted with (Ball Tracking) and a third indicated the location consistent with the actor’s belief about the ball’s location (Belief Tracking). Despite different task goals, all groups’ eye-movement patterns were consistent with belief analysis, and the No Instructions and Ball Tracking groups reported no explicit mentalizing when debriefed. These findings represent definitive evidence that humans implicitly track the belief states of others in an uncontrollable and unintentional manner.

Time perception and temporal order memory

The purpose of this research was to investigate the relation between the attentional resources underlying time perception and temporal order memory. Subjects made judgments about temporal attributes associated with a series of wordlists. Each word was displayed for 1.4s, and the lists contained 10 words (14s total), 15 words (21s total), or 20 words (28s total). Subjects judged either the list duration, the temporal order of the words, or both duration and temporal order. In addition, there were three mental workload conditions: control (no additional task requirements), and two mental arithmetic tasks (subtract 3 or subtract 7 from a series of random numbers). The results showed a pattern of bidirectional interference between timing and temporal order: the concurrent temporal order task interfered with duration judgments, and the concurrent timing task interfered with temporal order judgments. Bidirectional interference also occurred between the mental workload task and both duration judgments and temporal order judgments. The results indicate that duration and temporal order are closely related temporal attributes, and suggest that the processing of these attributes relies on a common set of executive attentional resources.

African Americans' Implicit Racial Attitudes and the Depletion of Executive Function after Interracial Interactions

Abstract Previous work has found that white individuals who harbor negative racial attitudes toward blacks are particularly likely to be depleted of executive attentional resources after interracial contact. The present study investigated whether engaging in interracial interactions also depletes the executive resources of black individuals as a function of their racial attitudes toward whites. Black participants completed an unobtrusive measure of racial attitudes, engaged in either an interracial or same-race interaction, and then completed an inhibitory response task to assess executive functioning. Similar to previous research, results revealed that blacks' racial attitudes predicted the extent to which they were impaired on the inhibitory response task after an interracial, but not after a same-race, interaction. Specifically, the more ingroup favoritism individuals revealed on the attitude measure, the more depleted of attentional resources they were after the interracial interaction. Taken together...