PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “cognitive control”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources
PubMed2003

Dissociable neural mechanisms underlying response-based and familiarity-based conflict in working memory.

Cognitive control requires the resolution of interference among competing and potentially conflicting representations. Such conflict can emerge at different points between stimulus input and response generation, with the net effect being that of compromising performance. The goal of this article was to dissociate the neural mechanisms underlying different sources of conflict to elucidate the architecture of the neural systems that implement cognitive control. By using functional magnetic resonance imaging and a verbal working memory task (item recognition), we examined brain activity related to two kinds of conflict with comparable behavioral consequences. In a trial of our item-recognition task, participants saw four letters, followed by a retention interval, and a probe letter that did or did not match one of the letters held in working memory (positive probe and negative probe, respectively). On some trials, conflict arose solely because of the current negative probe having a high familiarity, due to its membership in the immediately preceding trial's target set. On other trials, additional conflict arose because of the current negative probe having also been a positive probe on the immediately preceding trial, producing response-level conflict. Consistent with previous work, conflict due to high familiarity was associated with left prefrontal activation, but not with anterior cingulate activation. The response-conflict condition, when compared with high-familiarity conflict trials, was associated with anterior cingulate cortex activation, but with no additional left prefrontal activation. This double dissociation points to differing contributions of specific cortical areas to cognitive control, which are based on the source of conflict.

Conflict, Psychological↗
PubMed2006

Trial by trial effects in the antisaccade task.

The antisaccade task requires participants to inhibit the reflexive tendency to look at a sudden onset target and instead direct their gaze to the opposite hemifield. As such it provides a convenient tool with which to investigate the cognitive and neural systems that support goal-directed behaviour. Recent models of cognitive control suggest that antisaccade performance on a single trial should vary as a function of the outcome (correct antisaccade or erroneous prosaccade) of the previous trial. In addition, repetition priming effects suggest that the spatial location of the target on the previous trial may also influence current trial performance. Thus an analysis of contingency effects in antisaccade performance may provide new insights into the factors that influence the monitoring and modulation of the antisaccade task and other ongoing behaviours. Using a multilevel modelling analysis we explored previous trial effects on current trial performance in a large antisaccade dataset. We found (1) repetition priming effects following correct antisaccades; (2) contrary to models of cognitive control antisaccade error rates were increased on trials following an error, suggesting that failures to adequately maintain the task goal can persist across more than one trial; and (3) current trial latencies varied according to the previous trial outcome (correct antisaccade, slowly corrected error or rapidly corrected error). These results are discussed in terms of current models of antisaccade performance and cognitive control and further demonstrate the utility of multilevel modelling for analysing antisaccade data.

Adult↗
PubMed2004

The impact of glucose ingestion and gluco-regulatory control on cognitive performance: a comparison of younger and middle aged adults.

A great deal of research has been devoted to the issue of whether the ingestion of a glucose containing drink facilitates cognitive performance. However, it remains unclear exactly how age and individual differences in gluco-regulatory control mediate a boost in cognitive functioning. The present study investigates these issues further. A repeated measures (25 g vs 50 g glucose vs placebo) counterbalanced, double-blind design was used with 25 younger and middle-aged adults. A battery of memory and non-memory tasks was administered; including tests of episodic and semantic memory, attention and visuospatial functioning. Glucose ingestion largely facilitated performance on tasks with a memory component. Notably, task demands and age (young vs middle-aged) contributed to the magnitude of memory enhancement. This finding suggests an age- and load-specific benefit of glucose intake. In addition, evidence suggests greater facilitation in individuals with good glucose regulation. These data are discussed in relation to the idea that glucose specifically affects neural mechanisms supporting memory functioning (i.e. the hippocampus), which are known to decline in ageing. Importantly, the present investigation adds to the growing body of literature showing the utility of glucose supplementation as memory enhancers.

Adolescent↗
PubMed2001

Test-retest reliability of electrophysiological parameters related to cognitive motor control.

Previously, the continuous performance test was demonstrated to elicit distinct electrophysiological correlates of cognitive response during execution (Go) and inhibition (NoGo) of an anticipated motor response. A robust method for topographical quantification of these brain electrical microstates has been established recently. Test reliability is crucial to allow application in the assessment of neuropsychiatric disorders. The present study evaluates the reliability of the Go and NoGo centroid locations as well as the NoGo anteriorisation (NGA) in 23 healthy individuals. Our results show supreme test-alternate retest reliabilities of Pearson's product moment correlations and intraclass correlation coefficients of r> or =0.63 (P< or =0.001) for these parameters which assert a quality well within the range reported for those of other electrophysiological standard paradigms. Go and NoGo centroid locations as well as the NGA are, therefore, reliable correlates of prefrontal motor control and may contribute to the understanding of disorders with allied impairments.

Adult↗
PubMed1991

The impact of daily exercise on the mobility, balance and urine control of cognitively impaired nursing home residents.

The purpose of this intervention study was to examine the impact of a daily exercise regimen on the mobility, balance, and urine control of a sample of cognitively impaired elderly nursing home residents. A quasi-experimental pretest-posttest design was used with 15 elderly, cognitively impaired, incontinent nursing home residents. Data were collected regarding walking distance, speed of walking, balance ability, ability to rise from a chair unassisted, ability to walk unassisted, and incidence of urinary incontinence before and after a month of daily assisted walking. Subjects were able to walk significantly greater distances before tiring after the exercise regimen. In addition, the incidence of urinary incontinence was significantly decreased.

Aged↗
PubMed2006

Self-regulatory strategy and executive control: implementation intentions modulate task switching and Simon task performance.

Two tasks where failures of cognitive control are especially prevalent are task-switching and spatial Simon task paradigms. Both tasks require considerable strategic control for the participant to avoid the costs associated with switching tasks (task-switching paradigm) and to minimize the influence of spatial location (Simon task). In the current study, we assessed whether the use of a self-regulatory strategy known as "implementation intentions" would have any beneficial effects on performance in each of these task domains. Forming an implementation intention (i.e., an if-then plan) is a self-regulatory strategy in which a mental link is created between a pre-specified future cue and a desired goal-directed response, resulting in facilitated goal attainment (Gollwitzer in European Review of Social Psychology, 4, 141-185, 1993, American Psychologist, 54, 493-503, 1999). In Experiment 1, forming implementation intentions in the context of a task-switching paradigm led to a reduction in switch costs. In Experiment 2, forming implementation intentions reduced the effects of spatial location in a Simon task for the stimulus specified in the implementation intention. Results supported the prediction that the need for high levels of cognitive control can be alleviated to some degree by making if-then plans that specify how one responds to that critical stimuli.

Adult↗
PubMed2003

Mental fatigue and the control of cognitive processes: effects on perseveration and planning.

We tested whether behavioural manifestations of mental fatigue may be linked to compromised executive control, which refers to the ability to regulate perceptual and motor processes for goal-directed behaviour. In complex tasks, compromised executive control may become manifest as decreased flexibility and sub-optimal planning. In the study we use the Wisconsin Card Sorting Test (WCST) and the Tower of London (TOL), which respectively measure flexibility (e.g., perseverative errors) and planning. A simple memory task was used as a control measure. Fatigue was induced through working for 2 h on cognitively demanding tasks. The results showed that compared to a non-fatigued group, fatigued participants displayed more perseveration on the WCST and showed prolonged planning time on the TOL. Fatigue did not affect performance on the simple memory task. These findings indicate compromised executive control under fatigue, which may explain the typical errors and sub-optimal performance that are often found in fatigued people.

Adult↗
PubMedDate not supplied

Mode of inheritance influences behavioral expression and molecular control of cognitive deficits in female carriers of the fragile X syndrome.

The effect of mode of inheritance on expression of fragile X syndrome [fra(X)] was investigated in nonretarded female carriers. Examination included cognitive and molecular measures. A priori predictions about cognitive impairment and size of an unstable region of DNA containing a CGG repeat on the X chromosome were tested in age and education matched heterozygotes grouped according to parental inheritance. Nine carriers with a maternal fra(X) chromosome, 11 carriers with a paternal fra(X) chromosome and 15 control mothers of children with non X-linked developmental disabilities were tested. Inheritance was established through DNA linkage analysis. Cognitive skills were assessed using the Wechsler Adult Intelligence Scale-Revised and the Benton Visual Retention Test. Molecular status was assessed by Southern blot analysis of genomic DNA digested with Eco RI and Eag I, and probed with StB 12.3. Results supported the inheritance models' predictions. Heterozygotes who inherited the fra(X) from their fathers appeared to be a homogeneous group. They were indistinguishable from controls on cognitive measures and all had genomic insertions of less than 500 base pairs. In contrast, heterozygotes who inherited the fra(X) chromosome from their mothers appeared to be made up of 2 sub-populations. They were as a group deficient in measures of attention and visual memory, but not other measures, with scores of some women consistently below the other subjects. Further, they had some members with greater than 500 base pair inserts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2004

Anterior cingulate conflict monitoring and adjustments in control.

Conflict monitoring by the anterior cingulate cortex (ACC) has been posited to signal a need for greater cognitive control, producing neural and behavioral adjustments. However, the very occurrence of behavioral adjustments after conflict has been questioned, along with suggestions that there is no direct evidence of ACC conflict-related activity predicting subsequent neural or behavioral adjustments in control. Using the Stroop color-naming task and controlling for repetition effects, we demonstrate that ACC conflict-related activity predicts both greater prefrontal cortex activity and adjustments in behavior, supporting a role of ACC conflict monitoring in the engagement of cognitive control.

Adult↗
PubMed2001

[Prefrontal lobes and the attentional control: a neuropsychological study using modified Stroop test].

The prefrontal lobes may play an important role in attentional and cognitive control. The modified Stroop test can detect the disorder of this regulatory function in the brain-damaged patients. The Stroop conflict task was given to 35 prefrontal damaged patients (prefrontal group) and 20 subjects with temporal or parietal lesions (posterior group). The prefrontal subjects were further divided into the three subgroups, which consisted of 17 dorsolateral, 6 medial and 12 orbitofrontal patients. There were no significant differences between the prefrontal and posterior group on the Stroop test. However, the dorsolateral prefrontal damaged subgroup and the medial prefrontal damaged subgroup had significantly poor performances than the posterior group on the incongruent condition of the Stroop test. This findings indicated that the impairment of attentional control between the word reading and color naming resulted from the lesions of dorsolateral and medial part of prefrontal lobes. The cognitive control of visual attention may be supported by the neural substrates including dorsolateral prefrontal lobe, supplementary motor area and anterior cingulate cortex.

Attention↗
PubMedDate not supplied

Emotion regulation in the brain: conceptual issues and directions for developmental research.

Emotion regulation cannot be temporally distinguished from emotion in the brain, but activation patterns in prefrontal cortex appear to mediate cognitive control during emotion episodes. Frontal event-related potentials (ERPs) can tap cognitive control hypothetically mediated by the anterior cingulate cortex, and developmentalists have used these to differentiate age, individual, and emotion-valence factors. Extending this approach, the present article outlines a research strategy for studying emotion regulation in children by combining emotion induction with a go/no-go task known to produce frontal ERPs. Preliminary results indicate that medial-frontal ERP amplitudes diminish with age but become more sensitive to anxiety, and internalizing children show higher amplitudes than noninternalizing children, especially when anxious. These results may reflect age and individual differences in the effortful regulation of negative emotion.

Brain↗
PubMed2002

The distribution of 5-HT(6) receptors in rat brain: an autoradiographic binding study using the radiolabelled 5-HT(6) receptor antagonist [(125)I]SB-258585.

We used the highly selective 5-HT(6) receptor radioligand [(125)I]SB-258585 (4-iodo-N-[4-methoxy-3-(4-methylpiperazin-1-yl)phenyl]benzene-sulfonamide) to perform autoradiographic binding studies on the rat brain. High levels of specific binding occurred in the corpus striatum, nucleus accumbens, Islands of Calleja and the olfactory tubercle. A high level of binding also appeared in the choroid plexus. Moderate levels occurred in several regions of the hippocampal formation and in certain regions of the cerebral cortex, thalamus, hypothalamus, and substantia nigra; and very low levels in the globus pallidus, cerebellum, other mesencephalic regions, and the rhombencephalon. Displacement of total binding with 10 microM unlabelled SB-214111 (4-bromo-N-[4-methoxy-3-(4-methylpiperazin-1-yl)phenyl]benzene-sulfonamide), another selective 5-HT(6) receptor antagonist, or 10 microM unlabelled methiothepin, reduced binding to barely discernible levels. Some animals received unilateral injections of 6-hydroxydopamine (6-OHDA) into the median forebrain bundle to lesion the nigro-striatal pathway before autoradiographic examination. Effectiveness of the 6-OHDA lesions in the substantia nigra and striatum was confirmed with tyrosine hydroxylase immunohistochemistry. Such lesions resulted in no significant changes in [(125)I]SB-SB258585 binding in any brain region examined, suggesting that 5-HT(6) receptors in the striatum are not located on dendritic, somatic or terminal elements of dopaminergic neurones. Thus, the striatal binding sites seen in this study may be on intrinsic GABAergic or cholinergic neurones, or on terminals of projection neurones from the thalamus or cerebral cortex. The 5-HT(6) receptor ligand binding seen here in the striatum, accumbens, olfactory tubercle, Islands of Calleja, cerebral cortex and hippocampus are in concordance with previous immunohistochemical studies, and suggest a possible involvement of 5-HT(6) receptors in locomotor control, cognition, memory, and control of affect. The high levels of binding observed in the choroid plexus in this study have not been reported before. This finding suggests that 5-HT(6) receptors could play a role in the control of cerebrospinal fluid dynamics.

Animals↗
PubMedDate not supplied

Improved cognition after control of risk factors for multi-infarct dementia.

A cohort of 52 patients (30 men and 22 women) with multi-infarct dementia (MID) has been followed up prospectively for a mean interval of 22.2 months. Clinical course has been documented by serial history taking and interviews and neurological, medical, and psychological examinations, and correlated with measurements of cerebral blood flow. The clinical course and cognitive performance have been compared with those of age-matched normal volunteers and patients with Alzheimer's disease. Patients with MID were subdivided into hypertensive and normotensive groups, and also into those displaying stabilized or improved cognition and those whose condition deteriorated. Among hypertensive patients with MID, improved cognition and clinical course correlated with control of systolic blood pressure within upper limits of normal (135 to 150 mm Hg), but if systolic blood pressure was reduced below this level, patients with MID deteriorated. Among normotensive patients with MID, improved cognition was associated with cessation of smoking cigarettes.

Adult↗
PubMed2006

Brain regions underlying response inhibition and interference monitoring and suppression.

Response inhibition and interference monitoring and suppression are two important aspects of cognitive control. Previous functional imaging studies have suggested a common network of brain regions underlying these cognitive processes; the dorsolateral prefrontal cortex (DLPFC), the ventrolateral prefrontal cortex (VLPFC), the dorsal cingulate (dACC), and the parietal cortex (PC). The relative contribution of these regions to these cognitive subprocesses, however, has not been determined. Based on previous findings supporting a role for dACC in the monitoring of conflicting information within a stimulus, we hypothesized greater activity in this cortical region during interference monitoring and suppression relative to response inhibition. On the other hand, as response inhibition is characterized by differential cognitive processes such as control implementation, top down modulation of the response, expectancy, and inhibition of behavioural response, we hypothesized increased activity in the other cortical nodes of the cognitive control network relative to interference monitoring and suppression. To this end, we conducted an event-related functional magnetic resonance imaging (fMRI) study in 57 healthy volunteers using a task preferentially involving either interference monitoring and suppression or response inhibition. Accuracy for response inhibition was lower than for interference monitoring and suppression. Imaging data showed activation in DLPFC, dACC, VLPFC, PC for both conditions. Comparisons between the two conditions indicated greater activation bilaterally in DLPFC, VLPFC and PC during response inhibition, and greater activation in the dACC during interference monitoring and suppression. These results extend previous findings by suggesting regional functional specialization within a cortical network supporting cognitive control.

Adult↗
PubMed2006

Accounting for sequential trial effects in the flanker task: conflict adaptation or associative priming?

The conflict-control loop theory proposes that the detection of conflict in information processing triggers an increase in cognitive control, resulting in improved performance on the subsequent trial. This theory seems consistent with the robust finding that conflict susceptibility is reduced following correct trials associated with high conflict: the conflict adaptation effect. However, despite providing favorable conditions for eliciting and detecting conflict-triggered performance adjustments, none of the five experiments reported here provide unequivocal evidence of such adjustments. Instead, the results corroborate and extend earlier findings by demonstrating that the conflict adaptation effect, at least in the flanker task, is only present for a specific subset of trial sequences that is characterized by a response repetition. This pattern of results provides strong evidence that the conflict adaptation effect reflects associative stimulus-response priming instead of conflict-driven adaptations in cognitive control.

Adolescent↗
PubMed1983

Locus of control and cognitive behaviour therapy with mastectomy patients: a pilot study.

A cognitive behaviour therapy programme was designed for use with mastectomy patients, and a pilot study performed to test the efficacy of the programme. This article reports the locus of control data collected during the pilot study and the relationship between these data and the clinical assessment measures. Lower chance scores at pre-treatment are associated with greater clinical improvement as predicted. Surprisingly, however, there is an increase in chance scores over treatment although this disappears at follow-up. Patients who also received medication scored higher on internal control than those who did not. These results are discussed and it was concluded that antidepressant medication may assist the cognitive therapy programme.

Adjustment Disorders↗