Impaired Executive Control Research Articles

Executive control for methadone maintenance patients: an event-related potential study

Objective To discuss the neuropsychological mechanism of executive control for methadone maintenance patients( MMP). Methods Using the event-related potentials (ERPs) technique to reveal the time course of information processes with high temporal resolution, and exam the function of attention monitoring and response inhibition in heroin-dependent MMP. Results (1)The behavioral results: there were significant within-subjects Stroop interference effects for the MMP and control groups(reaction time: control group’s congruent condition(766.57±75.64)ms, incongruent condition(879.52±62.31)ms, MMP group’s congruent condition (821.89± 64.44)ms, incongruent condition(906.29±69.46)ms, P<0.001; error rate: control group’s congruent condition (4.15±2.92)%, incongruent condition(8.70±6.12)%, P<0.001, MMP group’s congruent condition(12.07±10.80)%, incongruent condition (16.60±12.43)%, P<0.01). (2)ERPs data showed that MMP demonstrated significantly smaller incongruent-N2/N450/SP amplitudes than controls, and all disappearing incongruent effects in N2, N450 and SP, comparing statistically significant incongruent effects for controls in N2, N450 and SP. In MMP group, the amplitudes of N2 and N450 incongruent condition(N2(1.40±2.91)μV、N450(1.29±0.55)μV) were bigger than congruent condition amplitudes(N2(0.77±3.61)μV、N450(0.83±1.07)μV, P<0.05), but the amplitude of SP (0.37±3.58)μV was smaller than congruent condition(1.53±3.05)μV, P<0.001; in control group, the amplitudes of N2 and N450 incongruent condition((-0.30±3.45)μV, N450(1.77±1.55)μV) were smaller than congruent condition (N2(1.10±3.64)μV, P<0.001; N450(2.37±2.12)μV, P<0.05), the amplitude of SP ((1.93±1.65)μV) was bigger than congruent condition((0.98±2.02)μV, P<0.01). Conclusion There are impaired executive control functions during the conflict monitoring process and the conflict resolution process for MMP. These results provide the neural electrophysiological evidence to explain relapse behaviors in methadone maintenance patients. Key words: Methadone maintenance patients; Stroop effect; Executive control; Event-related potentials

Repeated Detoxification of Alcohol-Dependent Patients Impairs Brain Mechanisms of Behavioural Control Important in Resisting Relapse

Alcohol abuse is frequently characterised by cycles of heavy drinking, detoxification, and relapse. We review evidence that multiple detoxifications are associated with impaired ability to control reward seeking, and with exaggerated responses to negative emotional stimuli. Under conditions of incentive conflict and in intra-extra dimensional shift and reversal tasks, deficits are found that are consistent with impaired executive control of behaviour by prefrontal cortical mechanisms. Correspondingly, alcoholics who have undergone multiple detoxifications show loss of grey matter in prefrontal regions associated with accurate performance of these tasks, the extent correlating with numbers of detoxifications. The ability to respond appropriately to certain emotional stimuli (e.g., fearful faces) is also impaired following multiple detoxifications. Such impairments are associated with reduced connectivity between insula and prefrontal areas but increased connectivity between insula and subcortical regions (colliculus), and between amygdala and other subcortical regions (bed nucleus of stria terminalis, BNST). Such changes may increase vulnerability to stress-induced relapse, and disrupt social abilities, contributing to social isolation.

Gait profiles as indicators of domain-specific impairments in executive control across neurodevelopmental disorders

In neurodevelopmental disorders, unique profiles of executive control and attention appear to co-occur with poor motor coordination. However, less is known about how syndrome-specific cognitive profiles interact with motor control and impact behavioural outcomes in neurodevelopmental disorders such as Williams syndrome (WS) and Down syndrome (DS). Here we aimed to examine the extent to which specific components of executive function interact with gait control when performing cognitive dual-tasks (verbal fluency, digit span) in WS and DS. Spatiotemporal gait characteristics and intra-individual variability of gait were assessed in individuals with WS who were matched on spatial ability to individuals with DS, and chronologically age (CA) matched controls. During the concurrent verbal fluency task, the WS group had greater dual-task costs on spatiotemporal gait parameters and variability than CA controls. Conversely, individuals with DS had selective gait interference during the concurrent digit span task when compared to CA controls, but only under increased demands on cognitive control where there was greater variability in step timing in DS. The interrelationships between cognitive-motor interference and behavioural measures of executive functioning appeared to differentiate between WS and DS, and emphasise the importance of task modality in unpacking the executive control profile in these neurodevelopmental disorders. These findings support the notion that associated cerebellar-cortico abnormalities may produce quite distinct profiles of executive control across cognitive and motor domains that impact on behavioural outcomes in neurodevelopmental disorders.

Attention processes in chronic fatigue syndrome: Attentional bias for health-related threat and the role of attentional control

Cognitive behavioural models of chronic fatigue syndrome (CFS) propose that attention processes, specifically, enhanced selective attention to health-threat related cues, may play an important role in symptom maintenance. The current study investigated attentional bias towards health-threat stimuli in CFS. It also examined whether individuals with CFS have impaired executive attention, and whether this was related to attentional bias. 27 participants with CFS and 35 healthy controls completed a Visual Probe Task measuring attentional bias, and an Attention Network Test measuring executive attention, alerting and orienting. Participants also completed self-report measures of CFS and mood symptoms. Compared to the control group, the CFS group showed greater attentional bias for health-threat words than pictures; and the CFS group was significantly impaired in executive attention. Furthermore, CFS individuals with poor executive attention showed greater attentional bias to health-threat related words, compared not only to controls but also to CFS individuals with good executive attention. Thus, this study revealed a significant relationship between attentional bias and executive attention in CFS: attentional bias to threat was primarily evident in those with impaired executive attention control. Taking account of individual differences in executive attention control in current intervention models may be beneficial for CFS.

Pilot study of cognition in children with unilateral hearing loss

ObjectiveThe objective of this study was to obtain preliminary data on the cognitive function of children with unilateral hearing loss in order to identify, quantify, and interpret differences in cognitive and language functions between children with unilateral hearing loss and with normal hearing. MethodsFourteen children ages 9–14 years old (7 with severe-to-profound sensorineural unilateral hearing loss and 7 sibling controls with normal hearing) were administered five tests that assessed cognitive functions of working memory, processing speed, attention, and phonological processing. ResultsMean composite scores for phonological processing were significantly lower for the group with unilateral hearing loss than for controls on one composite and four subtests. The unilateral hearing loss group trended toward worse performance on one additional composite and on two additional phonological processing subtests. The unilateral hearing loss group also performed worse than the control group on the complex letter span task. Analysis examining performance on the two levels of task difficulty revealed a significant main effect of task difficulty and an interaction between task difficulty and group. ConclusionsCognitive function and phonological processing test results suggest two related deficits associated with unilateral hearing loss: (1) reduced accuracy and efficiency associated with phonological processing, and (2) impaired executive control function when engaged in maintaining verbal information in the face of processing incoming, irrelevant verbal information. These results provide a possible explanation for the educational difficulties experienced by children with unilateral hearing loss.

Are stress and mixed urinary incontinence associated with impaired executive control in community-dwelling older women?

Objectives: To assess whether stress or mixed urinary incontinence (UI) is associated with deficits in executive functioning among community-dwelling women. Design: An observational study comparing the performance, using multivariate analyses of variance (MANOVAs) and Bonferroni post hoc test, of continent women and women with stress or mixed UI during executive control tasks. Setting: The research center of the Institut universitaire de gériatrie de Montréal. Participants: One hundred and fifty-five community-dwelling women aged 60 and older participated in the study. Measurements: Based on the Urogenital Distress Inventory (UDI), participants were split into three groups: 35 continent women, 43 women with stress UI, and 78 women with mixed UI. Participants completed a battery of neuropsychological tests and a computerized dual-task test. Results: Women with mixed UI showed poorer performances than continent and stress UI women in executive control functions. Deficits were specific to tests involving switching and sharing/dividing attention between two tasks. Conclusion: Results of this study suggest that mixed UI can be associated with executive control deficits in community-dwelling older women. Future intervention studies in the treatment of UI should take the higher risk of an executive control deficit in women with UI under consideration.

Reduced Specificity of Autobiographical Memory in Traumatized Adolescents: Exploring the Contributions of Impaired Executive Control and Affect Regulation

Reduced specificity of autobiographical memories retrieved to word cues on the Autobiographical Memory Test (AMT) associated with increased posttraumatic stress in traumatized samples has been already confirmed, though the researches for the adolescents are still not very substantial. Theoretical debates concerning the dominant influences on this effect have focused on affect regulation, whereby specific personal information is avoided more by those experiencing greater distress, versus impaired executive control, whereby increased distress is associated with an inability to set aside inappropriately general responses on the AMT. The present study compared these 2 views using AMT and AMT-R (the reversed version of the AMT) together. All the participants were recruited from a nonclinical and normal middle school. Participants (divided into three groups: high-PTSD, n = 31, low-PTSD, n = 32, and nontraumatic controls, n = 30)were required to generate specific memories response to emotion-related cue words in the AMT, whereas had to generate general memories from the past in the AMT-R. An emphasis on the role of affect regulation would predict that distress would be associated with reduced specificity (as in the standard AMT), whereas emphasis on the role of executive control would predict that this relationship should be reversed. The results indicated that, in contrast with the earlier studies, high-PTSD and low-PTSD groups behaved less specificity than nontraumatic controls and high-PTSD group also had generated less specific memories than low-PTSD group, regardless of cue valence in the AMT. But there were no significant differences of specific memories among the three groups in the AMT-R. The findings suggested that reduced autobiographical memory specificity has been demonstrated in traumatized adolescents in this study, and the results of AMT and AMT-R supported the affect regulation may play a greater role. Moreover, the clinical implications of the current research are discussed.

Failing to forget: prospective memory commission errors can result from spontaneous retrieval and impaired executive control.

Prospective memory (PM) research typically examines the ability to remember to execute delayed intentions but often ignores the ability to forget finished intentions. We had participants perform (or not perform; control group) a PM task and then instructed them that the PM task was finished. We later (re)presented the PM cue. Approximately 25% of participants made a commission error, the erroneous repetition of a PM response following intention completion. Comparisons between the PM groups and control group suggested that commission errors occurred in the absence of preparatory monitoring. Response time analyses additionally suggested that some participants experienced fatigue across the ongoing task block, and those who did were more susceptible to making a commission error. These results supported the hypothesis that commission errors can arise from the spontaneous retrieval of finished intentions and possibly the failure to exert executive control to oppose the PM response.

Recruitment of medial prefrontal cortex neurons during alcohol withdrawal predicts cognitive impairment and excessive alcohol drinking

Chronic intermittent access to alcohol leads to the escalation of alcohol intake, similar to binge drinking in humans. Converging lines of evidence suggest that impairment of medial prefrontal cortex (mPFC) cognitive function and overactivation of the central nucleus of the amygdala (CeA) are key factors that lead to excessive drinking in dependence. However, the role of the mPFC and CeA in the escalation of alcohol intake in rats with a history of binge drinking without dependence is currently unknown. To address this issue, we examined FBJ murine osteosarcoma viral oncogene homolog (Fos) expression in the mPFC, CeA, hippocampus, and nucleus accumbens and evaluated working memory and anxiety-like behavior in rats given continuous (24 h/d for 7 d/wk) or intermittent (3 d/wk) access to alcohol (20% vol/vol) using a two-bottle choice paradigm. The results showed that abstinence from alcohol in rats with a history of escalation of alcohol intake specifically recruited GABA and corticotropin-releasing factor (CRF) neurons in the mPFC and produced working memory impairments associated with excessive alcohol drinking during acute (24-72 h) but not protracted (16 -68 d) abstinence. Moreover, abstinence from alcohol was associated with a functional disconnection of the mPFC and CeA but not mPFC and nucleus accumbens. These results show that recruitment of a subset of GABA and CRF neurons in the mPFC during withdrawal and disconnection of the PFC-CeA pathway may be critical for impaired executive control over motivated behavior, suggesting that dysregulation of mPFC interneurons may be an early index of neuroadaptation in alcohol dependence.

Hyperthermia impairs the executive function using the Attention Network Test

Purpose: The primary aim of this study was to examine the effect of passive hyperthermia on the human attention system using the Attention Network Test (ANT), which has been used in both healthy controls and patients. Using target contrasts between conditions within a Flanker paradigm, the ANT can isolate three essential networks in the attention system: maintaining an alert state that is receptive to stimulus input and ready for responding; orienting, which involves selection of sensory input; and executive control, which monitors for and resolves conflict in responding or other aspects of cognitive processing.Materials and methods: The ANT was administered to 16 right-handed subjects in a heat stress condition (50°C, 40% relative humidity) and a control condition (20°C, 40% relative humidity), for 1 hour each. Reaction time (RT) and accuracy rate as well as mean body core temperature (T-core) and body weight loss were recorded.Results: Compared to the control condition, T-cores significantly increased and body weight was not significantly reduced in the heat stress condition. Overall, there were non-significant group differences for RT and accuracy rate. Although significant changes in neither alerting nor orienting effects were modulated by the simulated hyperthermia, the executive control effect on RTs was significantly larger in the heat compared to the control condition.Conclusions: Passive hyperthermia impaired executive control function, whereas alerting and orienting effects were unaffected.

Supplemental Material for Failing to Forget: Prospective Memory Commission Errors Can Result From Spontaneous Retrieval and Impaired Executive Control

Supplemental Material for Failing to Forget: Prospective Memory Commission Errors Can Result From Spontaneous Retrieval and Impaired Executive Control

Impaired Response Inhibition in Veterans with Post-Traumatic Stress Disorder and Mild Traumatic Brain Injury

Combat veterans with post-traumatic stress disorder (PTSD) can show impairments in executive control and increases in impulsivity. The current study examined the effects of PTSD on motor response inhibition, a key cognitive control function. A Go/NoGo task was administered to veterans with a diagnosis of PTSD based on semi-structured clinical interview using DSM-IV criteria (n = 40) and age-matched control veterans (n = 33). Participants also completed questionnaires to assess self-reported levels of PTSD and depressive symptoms. Performance measures from the patients (error rates and reaction times) were compared to those from controls. PTSD patients showed a significant deficit in response inhibition, committing more errors on NoGo trials than controls. Higher levels of PTSD and depressive symptoms were associated with higher error rates. Of the three symptom clusters, re-experiencing was the strongest predictor of performance. Because the co-morbidity of mild traumatic brain injury (mTBI) and PTSD was high in this population, secondary analyses compared veterans with PTSD+mTBI (n = 30) to veterans with PTSD only (n = 10). Although preliminary, results indicated the two patient groups did not differ on any measure (p > .88). Since cognitive impairments could hinder the effectiveness of standard PTSD therapies, incorporating treatments that strengthen executive functions might be considered in the future. (JINS, 2012, 18, 1-10).

Neurocognition, psychopathology, and subjective disturbances in schizophrenia: a comparison between short-term and remitted patients

Patients with schizophrenia present deficits in multiple domains of cognition. The study of the relationship between cognitive performance and symptoms of schizophrenia has yielded heterogeneous results. The purposes of this study were to examine the extent of the relationship between psychopathologic symptoms, cognitive function, and subjective disturbances in a group of patients affected by schizophrenia spectrum disorders and to compare short-term with remitted patients. Seventy-nine patients meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for schizophrenia, schizophreniform disorder, and schizoaffective disorder were assessed through the Positive and Negative Syndrome Scale, the Frankfurt Complaint Questionnaire, and a neuropsychologic battery exploring the 7 Measurement and Treatment Research to improve Cognition in Schizophrenia cognitive domains (speed of processing, attention/vigilance, working memory, verbal learning, visual learning, reasoning and problem solving, and social cognition) plus executive control. Neuropsychologic and psychopathologic variables were compared and correlated. Treatment groups did not differ in neuropsychologic and psychopathologic measures. The cognitive factor of the Positive and Negative Syndrome Scale correlated with worse performance on cognitive tasks and with higher scores on the Frankfurt Complaint Questionnaire 24 in the short-term, remitted, and combined groups. Subjective disturbances correlated with impaired executive control, reasoning and problem solving, and social cognition but not during the short-term phase. Both “objective” and subjective psychopathology are intertwined with cognitive function, suggesting some common underlying neural bases. The condition of being in a short-term or a remitted phase of the illness influences this interrelationship, regardless of the type of antipsychotic medication taken.

Impaired executive control of emotional information in social anhedonia

We examined the executive control of emotional information and its relationship to social functioning in individuals at risk for schizophrenia, defined by high social anhedonia (SA). Using the same structure as the Attentional Network Test (ANT), we developed a measure of executive control of emotional information (ANT-Emotion) in which subjects identify the direction of an arrow flanked by irrelevant angry or neutral faces. Subjects completed the ANT, ANT-Emotion, and the Social Adjustment Scale, Self-Report (SAS-SR), a measure of social functioning. While there were no group differences in the alerting, orienting, and executive control networks assessed by the ANT, high SA individuals exhibited a specific impairment in the executive control of emotional information. High SA individuals also reported poorer social functioning. However, executive control of emotional information did not mediate the relationship between SA and social functioning. These findings indicate that, in high-risk populations, the impaired ability to inhibit emotional information allows negative affective stimuli to exert inappropriate influence on cognitive processes. These results are consistent with studies indicating similar findings in schizophrenia patients, suggesting that impaired inhibition of negative emotion may be part of the liability for the disorder.

How does linguistic knowledge contribute to short-term memory? Contrasting effects of impaired semantic knowledge and executive control

Background: Linguistic knowledge makes an important contribution to verbal STM. Some theories, including Baddeley's original conception of the episodic buffer, hold that harnessing linguistic knowledge to support STM is executively demanding. However, some recent evidence suggests that the linguistic contribution does not depend on executive resources. Aims: In this study we tested the hypothesis that activation of language representations is automatic and that executive control is most important when the material to be remembered is incompatible with this automatic activation. Methods & Procedures: Word list recall was tested in three patients with transcortical sensory aphasia (TSA) following stroke. All had preserved word repetition and digit span but poor comprehension associated with impaired executive control. They were compared with two semantic dementia (SD) patients with degraded semantic representations but intact executive control. Patients repeated word lists that varied in their semantic and syntactic resemblance to meaningful sentences. Outcomes & Results: The executively impaired TSA patients showed large benefits of semantic and syntactic structure, indicating that their executive deficits did not interfere with the normal linguistic contribution to STM. Instead they showed severe deficits in repetition of scrambled word lists that did not follow usual syntactic rules. On these, the patients changed the word order to better fit their existing knowledge of syntactic structure. In contrast, the SD patients had no problems repeating words in unusual sequences but their semantic knowledge degradation led to frequent phonological errors due to a loss of “semantic binding”, the process by which semantic knowledge of words helps to constrain their phonological representation. Conclusions: These findings suggest that linguistic support for STM consists of (a) automatic activation of semantic and syntactic knowledge and (b) executive processes that inhibit this activation when it is incompatible with the material to be remembered.

Age-related decline in controlled retrieval: the role of the PFC and sleep.

Age-related cognitive impairments often include difficulty retrieving memories, particularly those that rely on executive control. In this paper we discuss the influence of the prefrontal cortex on memory retrieval, and the specific memory processes associated with the prefrontal cortex that decline in late adulthood. We conclude that preretrieval processes associated with preparation to make a memory judgment are impaired, leading to greater reliance on postretrieval processes. This is consistent with the view that impairments in executive control significantly contribute to deficits in controlled retrieval. Finally, we discuss age-related changes in sleep as a potential mechanism that contributes to deficiencies in executive control that are important for efficient retrieval. The sleep literature points to the importance of slow-wave sleep in restoration of prefrontal cortex function. Given that slow-wave sleep significantly declines with age, we hypothesize that age-related changes in slow-wave sleep could mediate age-related decline in executive control, manifesting a robust deficit in controlled memory retrieval processes. Interventions, like physical activity, that improve sleep could be effective methods to enhance controlled memory processes in late life.

Deficits in concept formation in amyotrophic lateral sclerosis.

Amyotrophic Lateral Sclerosis (ALS) is associated with impaired executive control. The aim of the current research was to test the hypothesis that concept formation deficits associated with an extramotor neurocognitive network involving executive and semantic resources can be found in some ALS patients. Forty-one patients with clinically definite ALS were assessed with Delis Kaplan Executive Function System Sorting Test (D-KEFS), a measure of concept formation requiring patients to manipulate verbal and visual semantic information and neuropsychological tests measuring naming, semantic memory, and executive control. Using D-KEFS scale scores, a k-mean cluster analysis specifying a 3-group solution was able to classify ALS patients into groups presenting with mildly impaired, average, and above average sorting test performance. High-resolution T1 structural MRI was used to examine cortical thickness in a subset of 16 ALS patients. Stepwise regression analyses related free and recognition sorting test performance to measures of action naming, single word semantic knowledge, and mental search/working memory. MRI studies found widespread cortical thinning involving bilateral frontal, temporal, and parietal regions. Regression analyses related recognition sorting performance to reduced MRI cortical thickness involving the left prefrontal and left parietal cortex. An extramotor cognitive network is associated with impaired concept formation in ALS.

Do Irrelevant Emotional Stimuli Impair or Improve Executive Control?

Our behavior is constantly influenced by emotional stimuli. These stimuli can enhance (i.e., improve) or impair performance, depending on their specific interaction with situational demands (Dolcos et al., 2011). This paper examines factors that mediate the influence of task-irrelevant negative stimuli on executive control (EC). We demonstrate how similar results of emotion-cognition interactions might be interpreted according to opposing theories, following the use of different analysis methods. Executive control is responsible for monitoring, controlling, and regulating irrelevant information, in order to enable goal-directed behavior (Norman and Shallice, 1986). Recently, there is growing debate regarding the influence of negative stimuli on EC (Hu et al., 2012). Specifically, compared to neutral stimuli, negative stimuli were found to impair (i.e., elongated reaction times – RT), improve (i.e., facilitated RT), or have no influence (i.e., similar RT) on EC. Herein we will first suggest that descriptions of improved or impaired EC may be misleading, and then discuss three factors that modulate links between EC and emotion: available resources, attentional breadth, and top-down modulation.

P-713 - A de novo microdeletion in chromosome 8q12.3q13.2: association with mild intellectual disability and epilepsy?

Whole genome microarray techniques are a primary tool for the etiological assessment in patients with intellectual disabilities. As a result, several novel microdeletions have been demonstrated that could be causatively related to the disorder. Interpretation of array results is facilitated through the use of databases such as the European Cytogeneticists Association of Unbalanced Chromosome Abberations (ECARUCA; http://www.ecaruca.net ). Clinical interpration of rare de novo microdeletions. Detailed evaluation of a young female with unexplained intellectual disability. Extensive neuropsychological, neurological, and genetic workup in a 9-years-old female patient with a history characterized by delay of psychomotor and speech development, mild to moderate intellectual disability and persistent sleep disturbances since the age of two. Several dysmorphic features were noticed including hypertelorism, downslanting palpebral fissures, a long, pear shaped nose, and low set, posteriorly rotated ears. Furthermore, she had a pectus excavatum, bilateral flat feet, and a sandal gap. Besides lowered intelligence, neuropsychological functioning disclosed impaired attentional capacities and executive control as well as weak motor skills. MRI of the brain disclosed no abnormalities. EEG demonstrated frequent epileptiform activity centroparietal bilaterally with marked increase during sleep, corresponding with continuous spike-waves during slow sleep (CSWS) syndrome. Array-CGH demonstrated a 3.57 Mb de novo microdeletion in chromosome 8q12.3. This de novo 8q12.3q13.2 microdeletion syndrome is characterized by a specific combination of a rare form of juvenile epilepsy (CSWS), neuropsychological dysfunction, impaired language and motor skills.

A de novo 3.57 Mb microdeletion in 8q12.3q13.2 in a patient with mild intellectual disability and epilepsy

A female patient, nine years of age, is reported with a history characterized by delay of psychomotor and speech development, mild to moderate intellectual disability and persistent sleep disturbances since the age of two. The patient showed facial dysmorphisms, a pectus excavatum and a sandal gap. Apart from lowered intelligence, neuropsychological functioning disclosed impaired attentional capacities and executive control as well as weak motor skills. Genome wide SNP array analysis revealed a 3.57 Mb de novo microdeletion in band q12.3 of chromosome 8. The long lasting sleep disorders turned out to originate from a rare juvenile epilepsy, continuous spike-waves during slow sleep (CSWS) syndrome, that includes the electrical status epilepticus in sleep (ESES) phenomenon. MRI-scanning of the brain showed no abnormalities.To the authors knowledge, this is the first report of a de novo 8q12.3q13.2 microdeletion syndrome that presents with ESES/CSWS.