Brain morphology in first-episode schizophrenic-like psychotic patients: a quantitative magnetic resonance imaging study

Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity.     

Interaction of permanently charged chlorpromazine and dopamine analogs with the striatal D-1 dopaminergic receptor

Although a structural feature common to all dopaminergic agonists and antagonists is a side-chain basic amino group, it is unclear whether this moiety binds to the D-1 dopamine (DA) receptor in the charged or uncharged form. To obtain information on this point, we synthesized permanently charged dimethylsulfonium and quaternary ammonium analogs of chlorpromazine and DA and determined whether these compounds can bind to the D-1 receptor by measuring their abilities to inhibit the binding of SCH 23390, a D-1 receptor antagonist. Chlorpromazine and the dimethylsulfonium and trimethylammonium analogs of chlorpromazine were found to inhibit the binding of [3H]SCH 22390, which was maximally inhibited to the same extent by all three compounds. In addition, inhibition curves for the compounds fit a one-site binding model, indicating binding to a single class of sites. However, while the permanently charged chlorpromazine analogs were able to inhibit [3H]SCH-23390 binding, they were considerably less potent than chlorpromazine. DA and dimethyl DA were also able to inhibit [3H]SCH 23390 binding. However, the permanently charged dimethylsulfonium and trimethylammonium analogs of DA were ineffective in inhibiting [3H]SCH 23390 binding. In addition, the permanently uncharged methylsulfide analog did not inhibit binding. These studies show that permanently charged analogs of chlorpromazine can bind to the striatal D-1 receptor, which is consistent with an anionic recognition site on the D-1 receptor that interacts with antagonists in the cationic form. In addition, it appears that a nitrogen atom is not required for binding to the D-1 receptor, since the sulfonium analog of chlorpromazine bound to the receptor to the same extent as chlorpromazine. However, since the permanently charged or uncharged analogs of DA did not bind to the D-1 receptor, it is still unclear as to whether the charged form of a dopaminergic agonist can bind. The lower potency or ineffectiveness of the permanently charged analogs compared to the parent amines (chlorpromazine, DA, dimethyl DA) in binding to the D-1 receptor may reflect the inability of the permanently charged analogs to undergo hydrogen binding with the anionic site of the receptor.     

Role of burst activity in attribute detection by visual neurons of the cat cortex

The temporal structure of neuronal responses has been investigated in the Clare-Bishop area of the cat cortex. Stationary and moving slit and moving spot have been used for stimulation. It was found that orientational and directional selectivity was determined mainly by the number of clustered impulses and the number of clusters. A closed-loop model for features detection which is able to interpret clustered activity is presented.     

Agoraphobics 5 years after imipramine and exposure. Outcome and predictors

Five years after treatment in a controlled trial, in which all had received self-exposure homework, a group of 40 agoraphobic outpatients retained marked improvement in agoraphobia, mood, and free-floating anxiety. Frequency of spontaneous panics decreased as much in those who had placebo and self-exposure as in those who received imipramine and self-exposure. Few patients, however, were completely well at 5 years and over half had received further treatment for agoraphobia during the follow-up. Patients who were still highly phobic at the end of the clinical trial were more often prescribed psychotropic medication during follow-up and remained phobic at 5 years. Phobic improvement had generalized more in those patients with very low than in those with moderate pretreatment Hamilton depression scores. Frequency of initial spontaneous panics did not predict outcome. Improvement in agoraphobia was associated with improved marital adjustment. Those who began with the best marital, work, and social adjustment were more improved in their phobias 5 years later.