Transformations in the couplings among intellectual abilities and constituent cognitive processes across the life span

Abstract— Two-component theories of intellectual development over the life span postulate that fluid abilities develop earlier during child development and decline earlier during aging than crystallized abilities do, and that fluid abilities support or constrain the acquisition and expression of crystallized abilities. Thus, maturation and senescence compress the structure of intelligence by imposing age-specific constraints upon its constituent processes. Hence, the couplings among different intellectual abilities and cognitive processes are expected to be strong in childhood and old age. Findings from a population-based study of 291 individuals aged 6 to 89 years support these predictions. Furthermore, processing robustness, a frequently overlooked aspect of processing, predicted fluid intelligence beyond processing speed in old age but not in childhood, suggesting that the causes of more compressed functional organization of intelligence differ between maturation and senescence. Research on developmental changes in functional brain circuitry may profit from explicitly recognizing transformations in the organization of intellectual abilities and their underlying cognitive processes across the life span.     

Eye movements and behavioral responses to threatening and nonthreatening stimuli during visual search in phobic and nonphobic subjects

Spider-phobic and nonphobic subjects searched for a feared/fear-relevant (spider) or neutral target (mushroom) presented in visual matrices of neutral objects (flowers). In half of the displays, the mushroom target was paired with a spider distractor, or a spider target was paired with a mushroom distractor. Although all subjects responded faster to the neutral target than to the feared/fear-relevant target, phobics were slower to respond than nonphobics when a mushroom target was presented with a spider distractor. Their eyes appeared to be drawn to the feared distractor before fixating neutral targets. A further experiment indicated no group differences when subjects merely judged the homogeneity of matrices. Thus, threat seems to capture the attention of phobics only when it is part of a background that subjects are explicitly instructed to ignore.     

Attention bias towards personally relevant stimuli: the individual emotional Stroop task

The emotional Stroop task is a widely used method for investigating attentional bias towards stimuli due to mood or affect. In general, standardized stimuli are used, which might not be appropriate when investigating individual contextual frameworks. It was investigated whether words chosen to be related to individuals' personal life events would produce more pronounced Stroop interference (as an indicator of attentional bias) than stimuli without any personal relevance. Twenty-six nonclinical subjects, 20 female and 6 male, participated in the study. Mean age was 36.1 yr. (SD = 18.1). All were recruited by means of local advertising. Stimulus material consisted of four word types: personal words related to negative life events with and without current personal relevance, and negative and neutral words without any personal relevance. Words were presented in three blocks. Analysis of variance showed main effects for word type and blocks, with slower reactions in the personally relevant conditions than in the negative, or neutral conditions, and in response to the first blocks as opposed to the last. These findings indicate that regardless of the word valence, personally relevant stimuli evoke more pronounced Stroop interference than do stimuli without personal relevance.     

Effectiveness of an empirically supported treatment for social phobia in the field

This study examined the effectiveness of individual exposure combined with cognitive restructuring for social phobia in a clinical setting as well as the influence of sample restriction criteria on the effect size. Participants were 217 unselected patients with a primary diagnosis of social phobia who were treated by 57 therapists in four outpatient clinics of the Christoph-Dornier-Foundation of Clinical Psychology in Germany. Results 6 weeks after the end of therapy showed highly significant reductions in social phobic fears and avoidance as well as in general anxiety and symptoms of depression. However, patients who dropped out during therapy reported a significantly higher degree of depression. Results did not differ between the four outpatient clinics and are comparable with the average effect-sizes reported by meta-analytic studies of controlled efficacy research, using selected patients. Also, restricting the sample according to the selection criteria often applied in research settings did not result in higher effect sizes for the applied outcome measures. We conclude that individual cognitive behavioural therapy for social phobia can be transported from research settings to the field of mental health.     

The perceived onset time of self- and other-generated actions

Awareness of actions is partly based on the intentions accompanying them. Thus, the awareness of self- and other-generated actions should differ to the extent that access to own and other's intentions differs. Recent studies have found a brain circuit (the mirror-neuron system) that represents self- and other-generated actions in an integrated fashion. This system does not respond to actions made by nonagents, such as machines. We measured the estimated onset time of actions that subjects either executed themselves or observed being executed by someone else or by a machine. In three experiments, the estimates of the machine actions always differed from those of self- and other-generated actions, whereas the latter two were indistinguishable. Our results are consistent with the view that intentions are attributed to others but not to machines. They also raise the interesting possibility that people attribute intentions to themselves in the same way as they do to others.     

Inactivation of the ventral tegmental area abolished the general excitatory influence of Pavlovian cues on instrumental performance

Pavlovian stimuli can markedly elevate instrumental responding, an effect known as Pavlovian-instrumental transfer (PIT). As the role of the ventral tegmental area (VTA) in PIT is yet unknown, we examined the effects of transient VTA inactivation by direct microinjections of a mixture of the GABA(A) and GABA(B) receptor agonists, muscimol and baclofen. Results reveal that PIT, i.e., the increase in instrumental responding during presentation of a Pavlovian stimulus, was abolished by intra-VTA microinjections of muscimol/baclofen. These data provide the first evidence that the VTA mediates Pavlovian influences on instrumental behavior.     

Dopamine D1 receptors in the anterior cingulate cortex regulate effort-based decision making

The anterior cingulate cortex (ACC) has been implicated in encoding whether or not an action is worth performing in view of the expected benefit and the cost of performing the action. Dopamine input to the ACC may be critical for this form of effort-based decision making; however, the role of distinct ACC dopamine receptors is yet unknown. Therefore, we examined in rats the effects of an intra-ACC D1 and D2 receptor blockade on effort-based decision making tested in a T-maze cost-benefit task. In this task, subjects could either choose to climb a barrier to obtain a high reward in one arm or a low reward in the other arm without a barrier. Unlike vehicle-treated rats, rats with intra-ACC infusion of the D1 receptor antagonist SCH23390 exhibited a reduced preference for the high-cost- high-reward response option when having the choice to obtain a low reward with little effort. In contrast, in rats with intra-ACC infusion of the D2 receptor antagonist eticlopride, the preference for the high-cost-high-reward response option was not altered relative to vehicle-treated rats. These data provide the first evidence that D1 receptors in the ACC regulate effort-based decision making.     

Parental Locus of Control and Family Functioning in the Quality of Life of Children with Sickle Cell Disease

The objective was to examine the association of parental locus of control (PLOC) with pediatric quality of life (QOL) for children with sickle cell disease (SCD), specifically addressing the potential mediating role of family functioning. Associations with disease severity were also investigated. Thirty-one primary caregivers completed standard measures of parental locus of control, family functioning, and quality of life during their child's inpatient admission for pain or fever. Results indicated that the PLOC total score was significantly associated with QOL in terms of self-competence and showed marginal significance with QOL social competence; it was significantly negatively correlated with family functioning. The association of the PLOC with QOL subscales was maintained when controlling for family functioning. Disease severity was not associated with PLOC scores. Primary caregivers endorsed more external parental locus of control beliefs. Further investigation of the association of caregiver appraisals and family functioning is warranted with the goal of addressing the stress that disease management with sickle cell may add to parent–child relationships.     

Does sound stimulation have additive effects on cognitive-behavioral treatment of chronic tinnitus?

Psychological and physiological habituation are major goals in the treatment of patients suffering from chronic tinnitus. This study evaluates whether sound stimulation provided by use of low level white noise generators (NG) enhances the effects of cognitive-behavioral treatment (CBT). 124 outpatients with tinnitus of >6 months received manualized group treatment and were randomly assigned to the NG/no NG conditions. Those with moderate tinnitus-related distress obtained four sessions focusing on education, while severely distressed subjects were treated according to a full 10-session CBT program. Outcome was assessed at post-treatment and at 6- and 18-month follow-up. No additive effects due to the NGs could be demonstrated. All groups improved significantly on measures of tinnitus-related distress, dysfunctional cognitions, general psychopathology, depression, hypochondriasis and psychosocial functioning. Beneficial effects of the NGs were only observed for patients with concurrent tinnitus and hyperacusis. As systematic physical stimulation of the auditory system does not further improve the effects of CBT, the importance and strength of psychological interventions are emphasized. The clinical relevance of recently developed "retraining" approaches accentuating physical stimulation should be reconsidered.