Maressa Hecht Orzack

The effects of daily administration of carphenazine on attention in the schizophrenic patient

SummaryChronic schizophrenic patients on daily administrations of carphenazine were clinically rated by two separate methods and measured by two types of performance tests. One was an attention test (CPT) and one a cognitive or associative test (DSST). Before medication the subjects performed poorly on the attention test but showed significant improvement during the course of medication. They showed no similar improvement on the cognitive test. Clinical improvement was also manifested and this correlated positively with improvement on the attention test. No such significant correlation existed between the DSST scores and the clinical ratings.The results of the study were discussed in light of the hypothesis that schizophrenic patients are hyperaroused. The fact that patients showed improvement on the CPT and not the DSST gave further evidence to support the hypothesis that phenothiazines have an effect on the selective areas of the brain and that these areas may be inherently related to the underlying factors in schizophrenia.

Physiological and behavioral correlates of attention dysfunction in schizophrenic patients.

SCHIZOPHRENIC patients usually perform poorer than normal subjects on most behavioral tasks. It is our contention that many of the behavioral deficits seen in the schizophrenic can be accounted for by a primary attentional disorder and/or a general lack of interest by the patient in playing the psychological games of the investigator. Much of the discordance in experiments with schizophrenic patients is probably due not only to the failure to obtain full participation of the patient, but also to failure to define adequately the study sample. Furthermore, experimental designs often suffer from the assumption that the disease state itself is a unitary function. Many investigators have attempted to subdivide their subject sample by subtype, i.e. paranoid versus non-paranoid, process versus reactive, good premorbid versus poor premorbid, etc; however, even this type of subdivision has often not given consistent results across a variety of experiments. In all of these studies the dividing of the schizophrenic sample into subtypes has been on the basis of some clinical characteristic of the patient and the dependent variable has been some performance measure. In the present report we will discuss a series of experiments in which we have used the opposite approach. The independent variable is the performance of the patients on a simple test of attention and the dependent variables are other performance tasks, various clinical subdivisions, and EEG recordings. The independent variable In previous work, we have found that the performance of approximately 40 % of chronic schizophrenics that we have tested on the Continuous Performance Test (CPT) is poorer than that of all normal subjects we have tested.1 We have interpreted this impairment as resulting from an attentional deficit. This attentional deficit has been found in schizophrenic patients who were in good remission and not on medication.2 Patients receiving antipsychotic medication are less likely to show an attentional deficit than patients not receiving such medication.lr3 The present paper will, for the most part, review those experiments in which we have compared schizophrenic patients with good performance on the CPT with those patients who do poorly on the CPT. The CPT consists of the presentation of stimuli, usually but not necessarily letters, in a random sequence at a constant rate and for a

A research note on some of the critical factors on the dissimilar effects of chlorpromazine and secobarbital on the digit symbol substitution and continuous performance tests

SummaryThe effects of single doses of chlorpromazine and secobarbital on performance of normal subjects on four behavioral tests were compared. The tests were the Continuous Performance Test (CPT), an experimenter-paced test requiring continued vigilence on the part of the subject; the Digit Symbol Substitution Test (DSST), a self-paced, cognitive test; the Subject-Paced Test (SPT), a test designed to include the same visual stimuli as those used in the CPT with the subject having control over the speed of presentation of the visual stimuli: and the Symbol Copying Test (SCT), a test designed to have all the motor, visual, and self-pacing components of the DSST with the cognitive aspect removed.The results support the hypothesis that chlorpromazine causes more decrement in performance than does secobarbital on experimenter-paced tests where sustained attention is necessary. However, on self-paced tests where sustained attention is not necessary, secobarbital causes more decrement in performance than does chlorpromazine. A self-paced test that is sensitive to barbiturates ceases to be a sensitive indicator of barbiturate effects when the cognitive aspect of the test is removed.

The importance of dosage in antipsychotic drug administration--a review of dose-response studies.

Methodologically adequate clinical dose-response studies with antipsychotic compounds are reviewed. A number of consistent findings have emerged. Treatment resistant schizophrenics, and schizophrenics under 40, hospitalized less than 10 years often benefit from high or very high doses of antipsychotics. Low dose treatment is to be considered for apathetic or depressed schizophrenics who are not floridly psychotic. Placebo or no medication is optimal for a hitherto not well defined subgroup. The usual clinical dose range appears to be most therapeutic for the remaining schizophrenic populations, probably including most out-patients. Methodological problems encountered in dose-response studies and clinical problems in posology are discussed.

Sleep deprivation deficits and their reversal by d-and l-amphetamine

Vigilance performance, waking EEG patterns and mood were studied before and after one night of sleep deprivation in normal males. The effects of d-amphetamine 10 mg, l-amphetamine 10 mg and placebo on these measures were compared. Changes were found in all three measures after one night of sleep-deprivation. d-Amphetamine was more powerful than l-amphetamine in reversing sleep deprivation effects on vigilance and on waking EEG.

A research report on the anti-fatigue effects of magnesium pemoline

SummaryThe effects of magnesium pemoline were compared to those of caffeine and methylphenidate on the performance of a nonmotivated task which required continuous attention over a two hour testing period. The drug treatment consisted of: 25 or 50 mg magnesium pemoline, 100 or 200 mg caffeine, 15 mg methylphenidate or a placebo. Ten unhospitalized volunteers were each tested six times, once on each treatment. The significant increase in errors which occured under placebo conditions did not occur with 50 mg magnesium pemoline, or 200 mg caffeine or 15 mg methylphenidate. These results support the contention of others that magnesium pemoline acts as a nonspecific CNS stimulant.

Psychosurgery Outcome and CNV Asymmetry

Publisher Summary This chapter discusses psychosurgery outcome and contingent negative variation (CNV) asymmetry. Event-related slow brain potentials are useful neurophysiological indicators of information processing. One brain wave complex, contingent negative variation (CNV), is a sensitive indicator of changes in brain functioning associated with impairment in attention processes. Moreover, there is evidence that CNV may provide a method of assessing brain lesion effects on psychological functions. The findings on split-brain and frontal lobe patients do not indicate hemispheric differences in CNV development. An attempt is made to assess the possible association between hemispheric differences in CNV development and clinical outcome following a bimedial prefrontal leukotomy. The fact that hemispheric differences characterize the CNV development of groups of psychosurgery patients with a more favorable and a less favorable outcome suggests that CNV asymmetries may be a useful, non-invasive method for the clinical assessment of behavioral changes following brain lesions. Normal subjects tend to show little or no lateral asymmetry in amplitude of CNV recorded either at the vertex or in areas other than motor cortex.

A comparison of the behavioral effects of periodic administration of chlorpromazine and a "sustained-release" form of chlorpromazine.

The relative efficacy of 300 mg. of chlorpromazine in a “sustained‐release” form was compared with repeated doses of regular chlorpromazine in a double‐blind crossover study. Ten sub;ects, 5 normal volunteers and 5 chronic schizophrenic patients, were given 4 psychomotor tests. Two of these, the CPT and PDS, were primarily attention tests. Performance on all the tests but the DSST indicated differences between the 2 treatments. A decrement in performance of the CPT was found 4 hours after the sustained‐release treatment; it did not persist. Decrement in performance was not found in the regular chlorpromazine program, suggesting an initial “dumping” effect of the sustained‐release capsule. Performance on the SPDT and PDS tests demonstrated latent differences between drug treatments. There were increasing decrements in performance after repeated regular chlorpromazine, suggesting a cumulative effect. This was not found after the sustained‐release treatment. While the sustained‐release treatment is as effective during the midportion of the period of observation as the repeated administration of regular chlorpromazine, the effects start to wear off between 8 to 10 hours after the administration of the sustained‐release capsule; while, after repeated doses of regular chlorpromazine, there were increasing decrements in performance.