Profiles of everyday executive function in acquired and developmental disorders.

Executive function profiles were examined within and between several clinical disorders via the multi-domain Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000). Parent ratings of children with Inattentive and Combined types of Attention-Deficit/Hyperactivity Disorder (ADHD-I, ADHD-C), Autistic Spectrum Disorders (ASD), moderate and severe Traumatic Brain Injury (TBI), and Reading Disabilities (RD) were compared with controls. Profile analysis revealed significant (p<.01) and substantial (eta2>.10) differences in global elevations and in profile of scale elevations between diagnostic groups. ASD, ADHD-I and ADHD-C groups exhibited greater elevations across the BRIEF scales than did RD and Severe TBI groups, who were in turn more elevated than Moderate TBI and Control groups. The ADHD-C group was unique in its frequency and severity of inhibitory deficits, while the ASD group was distinguishable by its deficits in flexibility. Within diagnostic groups, relative risk for executive dysfunction was calculated with variability present in the frequency of clinically elevated scales. While the BRIEF captures executive profiles characteristic of specific disorders in the clinical setting, it is not diagnostic in its own right and is best used within the context of a broad based evaluation.     

Sleep Disorders and Cognitive Dysfunctions in Parkinson’s Disease: A Meta-Analytic Study

Neuropsychology Review - A relationship between sleep disorders and cognitive dysfunctions was reported in Parkinson’s Disease (PD), however, some studies did not confirm the link. A...     

Attentional biases for threat after fear-related autobiographical recall

Background : Previous studies suggested that affective state could enhance stimulus salience and modulate attention allocation for mood-congruent information, but contrasting data have been reported on the effects of mood induction on attentional biases for threat (ABTs) in non-clinical individuals.

Objective : We aimed to assess whether laboratory-induced negative mood can increase individuals’ tendency to allocate attention on threatening stimuli, thus determining a difficulty in attentional disengagement from threat. We also aimed at assessing whether level of trait anxiety could modulate the effect of mood induction on attentional biases.

Methods : We used an autobiographical episode recall procedure for mood induction (fear, happiness and neutral episode recall), and an exogenous cueing task with threatening and non-threatening images to assess attentional biases in 120 undergraduate students.

Results: Participants showed a significant difficulty in disengaging attention from threat after recalling fear-related episodes, independently from their trait anxiety level.

Conclusions: These findings clarify that the ABTs are not exclusive to anxiety disorders or high trait anxiety individuals, and could also arise in non-clinical individuals in a fearful context.     

On the edge of language acquisition: inherent constraints on encoding multisyllabic sequences in the neonate brain

To understand language, humans must encode information from rapid, sequential streams of syllables – tracking their order and organizing them into words, phrases, and sentences. We used Near‐Infrared Spectroscopy (NIRS) to determine whether human neonates are born with the capacity to track the positions of syllables in multisyllabic sequences. After familiarization with a six‐syllable sequence, the neonate brain responded to the change (as shown by an increase in oxy‐hemoglobin) when the two edge syllables switched positions but not when two middle syllables switched positions (Experiment 1), indicating that they encoded the syllables at the edges of sequences better than those in the middle. Moreover, when a 25 ms pause was inserted between the middle syllables as a segmentation cue, neonates’ brains were sensitive to the change (Experiment 2), indicating that subtle cues in speech can signal a boundary, with enhanced encoding of the syllables located at the edges of that boundary. These findings suggest that neonates’ brains can encode information from multisyllabic sequences and that this encoding is constrained. Moreover, subtle segmentation cues in a sequence of syllables provide a mechanism with which to accurately encode positional information from longer sequences. Tracking the order of syllables is necessary to understand language and our results suggest that the foundations for this encoding are present at birth.     

The loyal member effect: on the preference for ingroup members who engage in exclusive relations with the ingroup

The goal of this article was to investigate an indirect form of intergroup differentiation in children in the context of racial attitudes: the preference for ingroup members who interact positively with other ingroup members rather than with outgroup members. Study 1 confirmed this general hypothesis with preschool and 1st-grade children, demonstrating that respondents preferred the ingroup member who played only with other ingroup members, evaluated this child more positively, and felt more similar to him or her. Studies 2 and 3 tested the boundary conditions of the phenomenon. Study 4 analyzed developmental changes demonstrating that the effect is no longer observed among 9- to 11-year-old children. Overall, these studies suggest that engaging in positive interactions with the outgroup might have its costs in terms of a relative devaluation and rejection by one's peers. Results are discussed by stressing the importance of intragroup processes for the regulation of intergroup relations among very young children.     

Working memory deficits in transgenic rats overexpressing human adenosine A2A receptors in the brain

Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients.     

Heart rate variability and drawing impairment in hypoxemic COPD

We studied 54 patients with hypoxemic chronic obstructive pulmonary disease (COPD). The Mini Mental State Examination and the Mental Deterioration Battery were used for neuropsychological assessment. Heart rate variability (HRV) was assessed based on 24-h Holter ECG recording. Mann–Whitney test was used to compare HRV parameters of patients performing normally or abnormally on individual neuropsychological tasks. Spearman’s rho was used to investigate the correlations between HRV parameters and neuropsychological scores, indexes of health status or COPD severity. Patients with defective performance at copying drawings with landmarks (CDL) test (N = 23) had lower very low frequency (VLF) power with respect to patients with normal performance (N = 31) (24 h: median 213; interquartile range 120–282 vs. 309; 188–431 ms², p = 0.043; daytime: 202; 111–292 vs. 342; 194–397 ms², p = 0.039). The CDL score correlated with the VLF power (24 h: ρ = 0.27, p = 0.049; daytime: ρ = 0.30, p = 0.028), and the normalized low frequency/high frequency (LF/HF) ratio (24 h: ρ = 0.27, p = 0.05; daytime: ρ = 0.33, p = 0.015). Sympathetic modulation decreased for increasing severity of COPD. In conclusion, drawing impairment correlates with depressed sympathetic modulation in patients with COPD, and both might be indexes of COPD severity.