I Lost It in the Lights: The Effects of Predictable and Variable Intermittent Vision on Unimanual Catching

In this study, 2 competing views of interceptive action were examined by assessing the influence of variability in the interval between visual samples in a unimanual ball-catching task. Subjects were required to catch tennis balls projected over a distance of 14 m, under conditions of intermittent vision in which the between-sample intervals were either predictable or unpredictable. Results indicated that, although performance was best with shorter between-sample intervals, the temporal predictability of samples did not reliably affect catching performance. This suggests that between-sample retinal expansion provides sufficient information for the timing of the interceptive act.

Aging and encoding in memory: false alarms and decision criteria in a word-pair recognition task

Employing a false alarm recognition procedure with learning of highly associated word pairs, an experiment was conducted to examine the hypothesis of an age-related deficit in the distinctiveness of encoding. The evolution of the false alarm rate and of the C decision criteria was observed across three age groups, young adults, older adults, and older-older adults. The results show 1) no age differences on C decision criteria, indicating that the increase in FA with age is not related to a subject compensation strategy but is probably due to a failure in memory strength, and 2) that older respondents produced significantly more false alarms to distractors related to target items than the young respondents did but that they did not differ in their false alarm rate for unrelated distractors. This finding is interpreted as supporting the hypothesis of a failure with age to encode target items in a sufficiently elaborate or distinctive fashion. For the older-older respondents the data showed an increase in all false alarms indexes, suggesting that the encoding deficit gets worse in late adulthood.

[Atypical depression: evolution toward a specific pharmacologic and efficacious treatment?]

The present article reviews different concepts of atypical depression. Of these, major depression associated with panic disorder would have a specific meaning according to some pharmacological and prognosis studies. It seems that this type of depression is quite frequent and has a significantly worse prognosis than major depression alone. Controlled studies comparing the efficacy of tricyclic antidepressants to phenelzine concluded in favour of the latter in general. It is generally thought that atypical depression would respond better to monoamine oxidase inhibitors (MAOI), but it would seem that it is mainly major depression associated with panic disorder that could predict this kind of response to treatment. Second generation antidepressants have not been studied systematically for this purpose even though preliminary reports seem promising.

A double-blind comparison of nefazodone, imipramine, and placebo in major depression

BACKGROUND

Nefazodone is a 5-HT2-receptor antagonist and serotonin (5-HT) selective reuptake inhibitor. This study evaluates the safety and efficacy of nefazodone in patients with major depressive disorder (MDD) in comparison to imipramine and placebo treatments. It also compares two dose ranges of nefazodone to investigate its optimal dose range.

METHOD

Nefazodone was evaluated in a 6-week, double-blind trial of novel design involving 180 patients meeting Research Diagnostic Criteria for major depressive disorder and having a minimum pretreatment score of 22 on the first 17 items of the Hamilton Rating Scale for Depression (HAM-D). Patients were randomly assigned to placebo (2-10 capsules/day), imipramine (50-250 mg/day), or nefazodone in two dose ranges (50-250 mg/day or 100-500 mg/day).

RESULTS

Improvement on depression measures with nefazodone in the 100-500-mg/day dose range (endpoint mean = 460 mg/day) and imipramine (endpoint mean = 214 mg/day) exceeded that with placebo. Some benefit was also observed in the nefazodone 50-250-mg/day treatment group (endpoint mean = 242 mg/day), but it was suboptimal. Evidence of nefazodone's efficacy as an antidepressant was consistently observed on physician- (HAM-D, Clinical Global Impressions [CGI]) and patient-rated (CGI-patient rated) scales. By patient self-report, improvement of anxiety symptoms associated with depression was evident with nefazodone as early as the first week of treatment, and benefit was seen with both nefazodone dosage groups. Analyses of the physician's global assessments of therapeutic effect and side effects at end of treatment showed therapeutic benefit for both nefazodone and imipramine treatments; however, patients in the nefazodone treatment groups were significantly less troubled by adverse experiences than were imipramine-treated patients, resulting in a lower dropout rate for adverse experience.

CONCLUSION

Nefazodone is a well-tolerated and effective antidepressant for the treatment of major depressive disorder.

Clonazepam in the treatment of panic disorder: a double-blind, placebo-controlled trial investigating the correlation between clonazepam concentrations in plasma and clinical response

Thirty-two outpatients with a DSM-III diagnosis of panic disorder or agoraphobia with panic attacks were randomly assigned to 4 weeks of treatment with clonazepam or placebo, after a 1-week placebo washout period. Twenty-nine patients entered the double-blind phase of the study and were eligible for intent-to-treat analysis. Clonazepam-treated patients experienced significantly fewer panic attacks, and these were of lesser intensity and short duration than those in placebo-treated patients (p < 0.001). Clonazepam was also superior to placebo with respect to symptoms of anxiety and depression (p < 0.001). The mean dose of clonazepam at week 4 was 2.2 mg (standard deviation, 0.7 mg). There was significant (p < 0.05) correlation between drug concentration in plasma and decrease in the global measure of the severity of panic disorder (r = 0.68); similar trends were seen for the decreases in frequency (r = 0.60) and severity (r = 0.55) of panic attacks, but not between concentration in plasma and decline in generalized anxiety. The most common adverse event was drowsiness, which occurred in 9 of 13 clonazepam-treated patients.

Sodium valproate and clonazepam for treatment-resistant panic disorder

Sodium valproate (VA) and clonazepam (CLZ) were combined in the treatment of 4 patients with panic disorders (PD) who were resistant to several antipanic drug treatments. A significant improvement was found in the symptomatology of these patients, but relapses occurred when CLZ dosage was reduced. A potentiation of the GABAergic properties of VA and clonazepam is postulated. This combined treatment could be advantageous for some treatment-resistant PD patients but needs to be studied further.

Clomipramine hydrochloride in childhood and adolescent obsessive-compulsive disorder--a multicenter trial

Children and adolescents with obsessive compulsive disorder were studied in an 8-week, multicenter, double-blind, parallel groups trial of clomipramine hydrochloride (CMI) versus placebo. Efficacy assessments included the child version of the Yale-Brown Obsessive Compulsive Scale and the National Institute of Mental Health Global rating scale. At the end of 8 weeks, CMI-treated patients showed a mean reduction in Yale-Brown Obsessive Compulsive Scale score of 37% compared to 8% in the placebo group. Side effects were typical of tricyclic antidepressants. In a 1-year open label treatment, CMI continued to be effective and well tolerated.

Panic disorder: vascular evaluation with transcranial Doppler ultrasonography

Several recent studies have shown neurophysiologic and neuroanatomic abnormalities in panic disorder. This study aimed to assess by transcranial Doppler (TCD) ultrasonography the magnitude of the changes in blood flow during panic attacks induced by intravenous sodium lactate infusion. The subjects consisted of 30 patients with panic disorder (DSM-III-R) and 25 controls; all were between the ages of 18 and 40 years and were right-handed. The flow in the middle cerebral artery was recorded bilaterally before the infusion began (to provide baseline readings) and at 3-minute intervals during the infusion. The patients showed a more rapid acceleration of flow (p less than 0.05) than the controls. Higher maximal velocity and higher variations in velocity (p less than 0.05) were observed in the patients sensitive to lactate but only in the right middle cerebral artery. These results suggest that abnormalities of local cerebrovascular autoregulation occurred in the patients with panic disorder during attacks induced by sodium lactate.

Immunocytochemical localization of xanthine oxidase in rat myocardium

Monoclonal antibodies (MAb's) to xanthine oxidase (XO) (from bovine milk) were produced by hybridoma technique. Culture supernatants were initially screened using enzyme-linked immunoabsorbant assay (ELISA). Forty four positive clones were subcloned and further characterized by ELISA and immunoblot analysis. Out of fifteen clones, which were positive in immunoblot analysis, one clone N2-26 was also positive in immunocytochemical studies. Indirect immunoperoxidase and enzyme histochemistry staining showed that XO activity is present in endothelial cells of capillaries, small blood vessels and also in interstitial cells. Electron microscopy revealed that diaminobenzidine reaction product was distributed in the cytoplasm of interstitial cells and endothelial cells of capillaries and small blood vessels. This is the first report of the presence of XO in interstitial cells and endothelial cells of small blood vessels. Allopurinol, which inhibits the xanthine oxidase activity, did not have any effect on the immunocytochemical staining. Our results in normal rat heart suggest that XO activity is confined to interstitial cells, endothelial cells of capillaries and small blood vessels.

Refractory depression: the addition of lithium to fluoxetine or desipramine

We carried out an open clinical study with 60 consecutive patients suffering from major depression with melancholia who were resistant to anti-depressants. After at least 6 weeks of desipramine (DMI) or fluoxetine (FX) without improvement, lithium carbonate was added to the anti-depressant. Semistructured clinical interviews using the 7-point Clinical Global Impression Scale and 90-item Symptom Checklist were done at baseline and weeks 1, 6 and 14. Following the addition of lithium, more patients on FX improved within the first week than those on DMI. However, with FX, 6 relapses occurred during the 2 months of follow-up and none with DMI. The unified serotonergic and noradrenergic hypothesis for the antidepressant action could be relevant in drug-refractory depression and should be studied further.

Probable interaction of sodium divalproex with benzodiazepines

1. After drug discontinuation and 1 week placebo washout, 12 patients with panic disorders received, for 6 weeks, either placebo or sodium divalproex. During 6 consecutive weeks, alternate medication was given. 2. Severity of panic and anxiety attacks was improved only in patients receiving sodium divalproex as a first medication. 3. Protracted benzodiazepine effects may occur in the dichotomous antipanic activity of sodium divalproex.

Lithium carbonate augmentation of desipramine in refractory depression

An open clinical study with 20 consecutive outpatients suffering from major depression with melancholia (DSM-III) was carried out. All patients were resistant to desipramine after at least six weeks of treatment. A significant improvement was found in 13 of the 20 patients when lithium carbonate was added. Among the responder patients, five improved in the first week of lithium augmentation, while eight others improved after one week of lithium. The mechanism of action of the lithium augmentation effect in tricyclic-resistant depressed patients is discussed in view of our findings. We suggest that the unified 5-HT/NE hypothesis used in affective disorder could be applied in drug refractory depression.

Positional behavior in Saimiri boliviensis and Ateles geoffroyi

Positional behavior, associated context, and substrate use in Ateles geoffroyi and Saimiri boliviensis were quantified using instantaneous focal animal sampling and a hierarchically organized nomenclature to describe posture and locomotion. This paper then examines behavioral predictions derived from pseudo-behavioral locomotor classifications, multivariate morphometric studies, and studies of the behavioral consequences of body size. The principal interspecific contrasts include (1) the superiority of Ateles with respect to locomotor and postural use of the forelimbs in tension, brachiation, arm swinging, dropping, quadrupedal climbing, forelimb dominated leaping/dropping take-offs and landings, suspensory posture, forelimb suspension, and use of larger and more complex supports; and (2) the superiority of Saimiri with respect to most forms of quadrupedal-cursorial locomotion and leaping, quadrupedal leaping/dropping take-off and landing patterns, locomotor and postural use of the limbs under compression, nonsuspensory posture, sitting, quadrupedal standing, and the use of twigs and single supports. In both animals, however, nonsuspensory postures and quadrupedal locomotion prevailed. Although behavioral findings were generally consistent with predictions derived from morphological accounts, the fit was loose. Discrepancies arose, especially concerning climbing and leaping. These were attributed to inadequacies in current nomenclature descriptive of positional behavior arising from the indiscriminate use of overinclusive vernacular and pseudo-behavioral terms.

Zopiclone and triazolam in insomnia associated with generalized anxiety disorder: a placebo-controlled evaluation of efficacy and daytime anxiety

In a double-blind placebo-controlled study, following a 1 week washout, 75 outpatients suffering from generalized anxiety disorder with severe insomnia as the target symptom were randomly assigned to 4 weeks of treatment with zopiclone 7.5 mg, triazolam 0.5 mg or placebo at bedtime. Zopiclone was significantly better than placebo on most sleep parameters. Triazolam tended to be superior to placebo, but its superiority was significant only on the sleep induction factor. Triazolam-treated patients presented significantly more day-time-interdose anxiety than zopiclone as assessed by the weekly HARS and Clinical Global Assessment of Anxiety. Although daytime-interdose anxiety was observed with both drugs, this treatment emergent symptom was more frequent and severe with triazolam. Side-effects were of a mild to moderate intensity for both zopiclone and triazolam; however, taste perversion frequently appeared with zopiclone. Although both drugs share similar pharmacological properties and bind to benzodiazepine receptors, they differ significantly with respect to side-effects and daytime anxiety.

Social phobia and clonazepam

Five patients meeting the DSM-III-R criteria for social phobia, without any other psychiatric diagnosis, were treated with clonazepam, a high potency benzodiazepine. All patients improved markedly within four weeks. By the end of the eighth week of treatment, a marked improvement of their symptoms was reported. The adverse effects were minimal at an average dose of 3 mg per day. The authors suggest that clonazepam is a safe and effective medication in the treatment of social phobia. Moreover, clonazepam is easier to use as compared to other drugs which are used (atenolol, phenelzine, alprazolam).

Valproic acid and panic disorder

Valproic acid (VA), an anticonvulsant which increases GABAergic transmission was given to patients suffering from recurrent panic attacks. Ten consecutive outpatients were included in this study. After a seven day placebo washout period, patients were given a dose of 500 mg/day, which was gradually increased to a maximum of 2250 mg/day. A significant improvement was found in the symptomatology of patients as measured on the Clinical Global Impression Scale for panic severity (p less than 0.001), the Hamilton Psychiatric Rating Scale for Anxiety (p less than 0.001) and the panic factor of the SCL-90 (p less than 0.05). These findings support the hypothesis that VA is useful in the treatment of panic disorders. Further research should be carried out to assess its efficacy and safety.

Temporal lobe abnormalities in panic disorder: an MRI study

Brain mapping studies have shown abnormal changes in cerebral blood volume and oxygen consumption, or other neurophysiological abnormalities, in panic disorder (PD) patients. Because of these intriguing reports, we decided to assess the neuroanatomical aspects of patients with PD using magnetic resonance imaging (MRI). We included 31 consecutive cases with a diagnosis of PD according to the DSM-III criteria, and 20 controls. All subjects had to be right-handed and between 20 and 40 years of age. The usual exclusion criteria were applied. We carried out the MRI tests with a General Electric Signa Machine operating at 1.5 Tesla. Over 100 images were obtained per patient with an emphasis on assessing temporal lobe. There were no significant differences in age, gender, or weight between the patients and controls. We found a statistically significant higher number of abnormalities in PD patients (40%), as compared with the controls (10%). The most striking findings were focal abnormalities in the temporal lobes: areas of abnormal signal activity, and asymmetric atrophy of the temporal lobe occurred mostly on the right side. These results implicated the limbic system and may prove to be of particular relevance in panic and phobic disorders. However, the significance of our findings remains unknown and challenging. Further MRI studies in PD will be required for a better understanding of the illness.