Biomedical subjects

P M Rennick

Publications and source records attributed to P M Rennick.

17 recordsLinked to original sources

PubMed1979

Decay and interference processes in short-term retention of normal and brain-damaged patients.

The present study examined decay and interference mechanisms in short-term verbal retention in brain damaged patients with and without clinical memory impairment. Petersons' distractor technique was modified for this purpose. Results indicated that decay and impaired consolidation of memory traces was greater in organic amnesics, accounting for a greater degree of forgetting than proactive interference. Absence of an interference function is discussed in terms of the modified technique utilizing repeated trials to recall and more rigorously eliminating covert rehearsal, in addition to employing a more representative sample of organic amnesics than in provious studies.

Adult↗

PubMed1978

Cognitive and evoked response measures of information processing in schizophrenics with and without a family history of schizophrenia.

Twenty-four male schizophrenics, 12 (SFH) with schizophrenia in the immediate family and 12 (SNFH) with no evidence of schizophrenia in the family background, and 24 male control subjects, 12 highly educated (HEC), and 12 minimally educated (MEC), were assessed for premorbid social adjustment and were administered the Digit Symbol Substitution Test, a size estimation task, and the EEG average evoked response (AER) at different levels of stimulus intensity. As predicted from the stimulus redundancy formulation, the SFH patients were poorer in premorbid adjustment, were less often paranoid, functioned at a lower level of cognitive efficiency (poor digit symbol and greater absolute error on size estimation), were more chronic, and, in some respects, had size estimation indices of minimal scanning. Contrary to prediction, the SFH group had the strongest and most sustained augmenting response on AER, while the SNFH group shifted from an augmenting to a reducing pattern of response. The relationship between an absence of AER reducing and the presence of cognitive impairment in the SFH group was a major focus of discussion.

Adult↗

PubMed1978

Organic impairment in polydrug users: risk factors.

In a national collaborative study to assess the neuropsychological status of 151 polydrug users, the Halstead-Reitan Neuropsychological Battery showed deficits in 37% two to three weeks after they entered treatment and in 34% at three-month follow-up. Comparative rates for a group of psychiatric patients were 26% and 27%, and for nonpatients, 8% and 4%. Extensive and intensive use of CNS depressants and opiates correlated positively with neuropsychological deficit. Older, less-educated subjects with adverse medical or developmental histories were more likely to show polydrug-related organic impairment. Although there is some evidence that such impairment is reversible, the condition appears to be of at least intermediate duration and may be long lasting.

Adult↗

PubMed1978

Evaluation of intellectual, linguistic, and achievement variables in normal, emotionally disturbed, and learning disabled children.

This study addresses itself to developing an abbreviated test battery to assess children presenting learning difficulties in the classroom. Factor analyses of the WISC, ITPA and PIAT revealed that 85% of the total variance of these tests can be accounted for by an abbreviated battery utilizing 12 subtests from the 26 in the total from all three tests. Evidence is presented that the discrepancy between academic achievement and academic aptitude is not as great as expected, in children with apparent underachievement, when careful, reliable measures are used.

Achievement↗

PubMed1977

A matched-subject comparison of underachievers with normals on intellectual, behavioral, and emotional variables.

Children labeled as underachievers are compared to a matched group functioning normally within the classroom. Factor analyses of the data from several tests reveal that the "normal" children not only have achieved higher academic performance but also have better learning aptitude. The inference may be made that many "underachievers" actually have a low general aptitude when carefully measured.

Achievement↗

PubMed1977

Neuropsychological deficit in polydrug users. A preliminary report of the findings of the collaborative neuropsychological study of polydrug users.

The Collaborative Neuropsychological Study of Polydrug Users performed extensive neuropsychological assessments on 15 polydrug users 3 weeks after their enrollment in each of eight polydrug demonstration programs. Fifty-six (37%) of these subjects exhibited neuropsychological deficit. This deficit was partially related to increasing age, poor education and premorbid medical risk factors. The deficit was also associated with extensive and intensive use of two classes of drugs: sedatives (sleeping pills and minor tranquilizers) and opiates (heroin and other narcotic drugs). Seventeen (26%) of a comparison group of 66 psychiatric in-patients and day patients also demonstrated age- and education-correlated neuropsychological deficit. For these patients impairment was also related to lifetime experience with antipsychotic drugs and (perhaps) with clinical diagnosis of schizophrenia. Although both polydrug users and psychiatric patients revealed serious psychopathology as measured by the MMPI, the pattern of the neuropsychological test findings suggested that psychopathology alone did not account for impairment. The 3 month follow-up which is in progress should delineate further the time course and enduring features of neuropsychological deficit among polydrug users, and may establish more clearly the relationship of sedative and opiate use to such impairment. Changes in psychopathological status of both polydrug users and psychiatric patients should also help to clarify the influence of this variable on neuropsychological findings.

Adult↗

PubMed1976

A comparison of the effectiveness of primidone versus carbamazepine in epileptic outpatients.

Prior to the release of carbamazepine for the treatment of patients with psychomotor and grand mal seizures, primidone was regarded as the drug of choice for these disorders, especially when combined with diphenylhydantoin (DPH). It was, therefore, of interest to compare the effectiveness of carbamazepine against primidone when added to a therapeutic dose of DPH. Forty-five patients completed a 6-month study with each patient serving as his own control. The patients were initially stabilized on therapeutic doses of DPH and one of the test compounds, while all other medications were withdrawn. After 3 months of treatment, they were transferred onto the other drug for a second 3-month period. Extensive laboratory testing, including anticonvulsant levels, electroencephalograms, and neuropsychological evaluations, was performed. For the most part, the patients remained on outpatient status, returning for reports of seizure frequency, side effects, and laboratory studies every 14 days. The study was conducted in a single blind fashion by the treating neurologists; double blind by the electroencephalographer and psychologists. The results indicated that the two drugs did not differ in their effectiveness on seizure control. There were somewhat more side effects--none serious--with carbamazepine than with primidone. The EEG showed increased fast activity with primidone and increased theta activity with carbamazepine. There was no difference in regard to decrease of electroencephalographic seizure discharges. The patients showed more impairment on a repeatable neuropsychological test battery with primidone than with carbamazepine, and they also showed an increase on the psychopathic deviate scale of the Minnesota Multiphasic Inventory. Depressive feelings, when present, lessened while under treatment with carbamazepine. The results suggest that patients with the seizure types under consideration and who do not respond to DPH alone or to a DPH-phenobarbital combination can be placed on either carbamazepine or primidone while phenobarbital is discontinued. A patient who is intellectually and emotionally intact with no past history of behavioral disturbances may do better on primidone than carbamazepine, because this drug gives fewer side effects. On the other hand, those patients who have a past history of emotional and/or intellectual disturbances may profit more from carbamazepine.

Adolescent↗

PubMed1974