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Objective: An ecologically valid adaptation of the irrelevant sound effect paradigm was employed to examine the relative roles of short-term memory, selective attention, and sustained attention in ADHD. Method: In all, 32 adults with ADHD and 32 control participants completed a serial recall task in silence or while ignoring irrelevant background sound. Results: Serial recall performance in adults with ADHD was reduced relative to controls in both conditions. The degree of interference due to irrelevant sound was greater for adults with ADHD. Furthermore, a positive correlation was observed between task performance under conditions of irrelevant sound and the extent of attentional problems reported by patients on a clinical symptom scale. Conclusion: The results demonstrate that adults with ADHD exhibit impaired short-term memory and a low resistance to distraction; however, their capacity for sustained attention is preserved as the impact of irrelevant sound diminished over the course of the task.

Objective: To determine the potential effectiveness of a behavioural weight control programme including physical exercise in the prevention of antipsychotic-induced weight gain and associated comorbid conditions in outpatients with schizophrenia and mood disorders. Methods: A prospective, comparative, open and naturalistic study was carried out for a total of 110 patients with schizophrenia, schizoaffective or bipolar disorders (DSM-IV), on treatment with atypical antipsychotics. Of these, 59 patients participated in an 18 month weight control programme that included an educational activity about dietary and physical activity counselling as well as a structured, supervised, facility-based exercise programme. The control group consisted of 51 patients with the same baseline characteristics who did not receive the clinical programme. Anthropometric measurements, plasma lipid–lipoprotein profile, and fasting plasma glucose concentrations were assessed at 11 time-points over the study. In addition, serum concentrations of prolactin, thyrotropin-stimulating hormone (TSH), and glycated haemoglobin (HbA1c) were assessed at four time-points. Finally, the Clinical Global Impression scale (CGI), the Brief Psychiatric Rating Scale (BPRS) and the Short Form (SF)-36 Health Survey were used. Results: The adherence rate of patients was 85%, both in the active and in the control group. Whereas the control group experienced a significant increase in bodyweight (4.1%), body mass index (BMI; 5.5%) and waist circumference (WC; 4.2%), the active group significantly reduced their bodyweight (−3.5%), BMI (−4.4%), and WC (−4.6%) at the study end-point. In addition, a significant increase in low-density lipoprotein (LDL)-cholesterol (14.8%) and in triglyceride concentrations (12.3%) was observed at month 18 in the control group. In contrast, high-density lipoprotein-cholesterol (HDL) significantly increased (21.4%), and LDL cholesterol (−13.7%), triglycerides (−26.2%), total cholesterol (−12.1%), fasting glucose concentrations (−12.0%), and HbA1c (−11.4%) significantly decreased compared to baseline in the active group. No significant changes were observed regarding serum concentrations of prolactin and TSH during the study. In regard to the changes observed in psychological measures, no between-group differences were seen in the clinical ratings of CGI and BPRS. However, the SF-36 showed that physical health was improved only for subjects in the active group at months 12 and 18 compared to baseline (p Conclusion: Bodyweight and metabolic risk profile in patients receiving atypical antipsychotic medications can be effectively managed with a weight control programme including physical activity.

Performance on the Stroop Color-Word Test is impaired in depression, but it is not clear whether this impairment reflects a distractor inhibition disturbance or a reduction of processing resources. In this study, untreated major depressives were evaluated using a modified computerized Stroop Test composed of three tasks: to name the color of XXXXXs, of nonconflicting words, and of conflicting color words. It was hypothesized that, unlike color words, nonconflicting word distractors would disturb the color naming task only in the presence of a primary distractor inhibition disturbance. The slow reaction time (RT) depressives and normal RT depressives, according to their color naming speed without distractors, were contrasted to distinguish depressives with and without clear signs of resource deficit. It was found that interference produced by nonconflicting words was greater in normal RT depressives than in either slow RT depressives or control subjects, while interference caused by color words was dramatically stronger in slow RT depressives than in other groups. Results suggest the existence of two different attentional deficit patterns in clinical depression: some depressives have a distractor inhibition disturbance while others are deficient in processing resources.

Cognitive impairments in depression have recently been proposed as secondary to more basic attentional disturbances. Studies have shown that performance on the Stroop Color-Word Test is impaired in depressives, but it is not clear whether this impairment reflects a primary distractor inhibition disturbance or a more global cognitive dysfunction, such as a reduction of processing resources. In the present study, unmedicated clinical depressives were evaluated using a computerized Stroop Color-Word Test and the Visuo-Spatial Interference Test, a selective attention task that makes fewer demands on resources. Compared with normal subjects, depressives presented increased choice reaction times (CRT) and interference in both tests. Correlations were found between CRT and interferences only in depressives, favoring the processing resource hypothesis. Further exploratory analysis comparing the more rapid depressives and the slower normal subjects on CRT revealed that although these subgroups had comparable CRT, rapid depressives still exhibited increased interference on the Visuo-Spatial Interference Test. Thus, in non- or mildly retarded patients, a specific distractor inhibition deficit was observed in absence of resource deficit.

Oestrogens are known to exert specific stimulatory effects on basal and dopamine (DA)-inhibited prolactin (PRL) release as well as on PRL cell content in rat adenohypophysial cells in primary culture. Recently, we have demonstrated that classical oestrogens increase growth hormone (GH) release and cellular GH content in rat pituitary somatotrophs. Since there is evidence that 5-androstene-3 beta, 17 beta-diol (delta 5-diol), a metabolite of dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEA-S) can induce typical oestrogenic responses in target tissues, we have investigated the effect of C19 adrenal steroids and compared them to that of 17 beta-oestradiol (E2) on the above-indicated parameters. Following a 72-h incubation, maximal concentrations of E2, delta 5-diol and DHEA caused a similar increase in PRL cell content at respective EC50 values of 0.020, 14 and 115 nM. The sensitivity of lactotrophs to DA action was decreased by approximately 4-fold after a 48-h exposure to maximal concentrations of delta 5-diol or DHEA. The time course of the antidopaminergic effect of delta 5-diol and DHEA was almost superimposable to that of E2. A 72-h incubation with 5 microM DHEA-S, a concentration within the range of blood levels found in women, doubled (P less than or equal to 0.001) cellular PRL accumulation. On the other hand, androstenedione (delta 4-dione) was without effect on any of the parameters measured. All stimulatory effects induced by maximal effective concentrations of delta 5-diol, DHEA or DHEA-S were competitively inhibited by simultaneous incubation with the antioestrogen LY156758. The amplitude of the stimulatory effects of delta 5-diol and DHEA on GH cell content as well as on spontaneous GH-releasing factor (GRF)-induced GH release was superimposable to that observed with E2. The effect of the steroids on GH cell content was exerted at 0.016 nM (E2), 12 nM (delta 5-diol) and 250 nM (DHEA). Simultaneous incubation with LY156758 completely blocked the effect of maximally effective concentrations of E2, delta 5-diol and DHEA in somatotrophs. Furthermore, a physiological concentration of DHEA-S (5 microM) enhanced spontaneous as well as GRF-induced GH release. On the other hand, delta 4-dione as well as testosterone and dihydrotestosterone did not alter GH release. The present data demonstrate that delta 5-diol, DHEA and DHEA-S can exert full oestrogenic effects in lactotrophs and somatotrophs, thus supporting their potential oestrogenic role under both physiological and pathological conditions.

The estrogenic activity of phenol red, a pH indicator widely used in cell culture media, was studied in rat anterior pituitary cells. After 72 hours of incubation with 40 microM phenol red, a 40-50% increase in prolactin cell content and a 100% stimulation of luteinizing hormone-releasing hormone induced luteinizing hormone release was observed. Both effects could be completely reversed by simultaneous incubation with the antiestrogen LY156758. In the rat uterine [3H] estradiol binding assay, phenol red showed a significant displacement at concentrations above 10 microM while its concentration in the commonly used culture media is about 40 microM. From the present results, we conclude that phenol red acts as a weak estrogen in normal tissues and that its estrogenic activity should be taken into account in studies using estrogen-sensitive cell or tissue cultures.