Cognitive control: dynamic, sustained, and voluntary influences

The cost of incongruent stimuli is reduced when conflict is expected. This series of experiments tested whether this improved performance is due to repetition priming or to enhanced cognitive control. Using a paradigm in which Word and Number Stroop alternated every trial, Experiment 1 assessed dynamic trial-to-trial changes. Incongruent trials led to task-specific reduction of conflict (trial n + 2) without cross-task modulation (trial n + 1), but this was fully explained by repetition priming. In contrast, an increased ratio of incongruent words did lead to sustained task-specific enhancement, above and beyond repetition priming (Experiment 2). Experiments 3 and 4 assessed the voluntary modulation of cognitive control: A cue predicted the congruency of the incoming trial, allowing participants to establish the correct mindset (Word Stroop in Experiment 3, Flanker task in Experiment 4). Preparing oneself to process an incongruent word (or flanker) enhanced conflict resolution in the subsequent Number Stroop, an example of cross-task modulation. Taken together, these experiments reveal the multifaceted aspects of conflict resolution: Trial-to-trial changes are often due to repetition priming; sustained modulations brought about by task demands are task specific; and voluntary modulations are task general.     

Neuropsychological performance in patients with fibromyalgia syndrome: relation to pain and anxiety

Previous studies have revealed the presence of cognitive impairment in patients with fibromyalgia syndrome (FMS). However, they have not determined the possible influence of the diverse clinical variables in these disturbances. The first aim of the current study is to compare the cognitive function of 81 patients with FMS and 35 healthy controls by means of a neuropsychological battery. The second aim is to determine the influence of anxiety and pain in the cognitive impairment of patients with FMS. The results of our study show that patients with FMS display a significantly lower cognitive performance and a significantly higher anxiety level than the healthy controls in all the parameters assessed. The neuropsychological performance in patients with FMS is associated with pain, and this relation was independent of the anxiety level. The relationship between cognitive performance and anxiety level was also significant. Therefore, we conclude that cognitive performance is primarily affected by pain. The level of anxiety explains part of the variability in neuropsychological tests that is not explained by pain.     

Selective attention in early Dementia of Alzheimer Type

This study explored possible deficits in selective attention brought about by Dementia of Alzheimer Type (DAT). In three experiments, we tested patients with early DAT, healthy elderly, and young adults under low memory demands to assess perceptual filtering, conflict resolution, and set switching abilities. We found no evidence of impaired perceptual filtering nor evidence of impaired conflict resolution in early DAT. In contrast, early DAT patients did exhibit a global cost in set switching consistent with an inability to maintain the goals of the task (mental set). We discuss these findings in relation to the DAT literature on executive attention, dual-tasking, and working memory.     

The association between life events and suicide intent in self-poisoners with and without a history of deliberate self-harm: a preliminary study

The associations between life events in the 12 months preceding an episode of self-poisoning resulting in hospital attendance (the index episode), and the suicide intent of this episode were compared in individuals for whom the index episode was their first, episode and in individuals in whom it was a recurrence of DSH. Results indicated a significant interaction between independent life events, repetition status, and gender in the prediction of suicide intent, the association between life events and intent being moderated by repetition status in women only. The results provide preliminary evidence to suggest the presence of a suicidal process in women, in which the impact of negative life events on suicide intent diminishes across episodes.     

Cross-national comparisons of the association between alcohol consumption and deliberate self-harm in adolescents

How differences in drinking patterns may affect the impact of alcohol consumption on deliberate self-harm among adolescents is explored in this international comparative study. Schools in Australia, Belgium, England, Hungary, Ireland, the Netherlands, and Norway (N = 30,532) were surveyed. In all countries the risk of deliberate self-harm was significantly elevated among adolescents who reported some or numerous episodes of intoxication, controlling for confounding factors. The results support the assumption that intoxication is significantly related to the association between alcohol consumption and deliberate self-harm in adolescents.     

Inhibition of action, thought, and emotion: A selective neurobiological review

The neural bases of inhibitory function are reviewed, covering data from paradigms assessing inhibition of motor responses (antisaccade, go/nogo, stop-signal), cognitive sets (e.g., Wisconsin Card Sort Test), and emotion (fear extinction). The frontal cortex supports performance on these paradigms, but the specific neural circuitry varies: response inhibition depends upon fronto-basal ganglia networks, inhibition of cognitive sets is supported by orbitofrontal cortex, and retention of fear extinction reflects ventromedial prefrontal cortex–amygdala interactions. Inhibition is thus neurobiologically heterogeneous, although right ventrolateral prefrontal cortex may support a general inhibitory process. Dysfunctions in these circuits may contribute to psychopathological conditions marked by inhibitory deficits.     

Sleep disturbances in depressed pregnant women and their newborns

Pregnant women (N=253) were recruited during their second trimester of pregnancy (M=22.3 weeks gestation) and assigned to depressed (N=83) and non-depressed groups based on a SCID diagnosis of depression. They were then given self-report measures on sleep disturbance, depression, anxiety and anger, and their urine was assayed for norepinephrine and cortisol. These measures were repeated during their third trimester (M=32.4 weeks). Their newborns were then observed during sleep. During both the second and third trimesters, the depressed women had more sleep disturbances and higher depression, anxiety and anger scores. They also had higher norepinephrine and cortisol levels. The newborns of the depressed mothers also had more sleep disturbances including less time in deep sleep and more time in indeterminate (disorganized) sleep, and they were more active and cried/fussed more.     

Preterm infants show reduced stress behaviors and activity after 5 days of massage therapy

Preterm infants residing in an NICU were randomly assigned to a massage therapy or to a control group. The preterm infants in the massage therapy group received three 15-min massages each day for 5 consecutive days, with the massages consisting of moderate pressure stroking to the head, shoulders, back, arms and legs and kinesthetic exercises consisting of flexion and extension of the limbs. Infant stress behaviors and activity were recorded on the first and last day of the study. Preterm infants receiving massage therapy showed fewer stress behaviors and less activity from the first to the last day of the study. The findings suggest that massage has pacifying or stress reducing effects on preterm infants, which is noteworthy given that they experience numerous stressors during their hospitalization.     

Task feedback effects on conflict monitoring and executive control: relationship to subclinical measures of depression

Emerging evidence suggests that depression is associated with executive dysfunction, particularly after committing errors or receiving negative performance feedback. To test this hypothesis, 57 participants performed two executive tasks known to elicit errors (the Simon and Stroop Tasks) during positive or negative performance feedback. Participants with elevated depressive symptoms (Beck Depression Inventory scores >or= 13) were characterized by impaired posterror and postconflict performance adjustments, especially during emotionally negative task-related feedback. Additionally, for both tasks, depressive symptoms were inversely related to postconflict reaction time adjustments following negative, but not positive, feedback. These findings suggest that subclinical depression is associated with impairments in behavioral adjustments after internal (perceived failure) and external feedback about deficient task performance.