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Biomedical subjects

N J Cohen

Publications and source records attributed to N J Cohen.

11 recordsLinked to original sources
PubMed1991

Cognitive representations and processes in arithmetic: inferences from the performance of brain-damaged subjects.

In this article, we present data from two brain-damaged patients with calculation impairments in support of claims about the cognitive mechanisms underlying simple arithmetic performance. We first present a model of the functional architecture of the cognitive calculation system based on previous research. We then elaborate this architecture through detailed examination of the patterns of spared and impaired performance of the two patients. From the patients' performance we make the following theoretical claims: that some arithmetic facts are stored in the form of individual fact representations (e.g., 9 x 4 = 36), whereas other facts are stored in the form of a general rule (e.g., 0 x N = 0); that arithmetic fact retrieval is mediated by abstract internal representations that are independent of the form in which problems are presented or responses are given; that arithmetic facts and calculation procedures are functionally independent; and that calculation algorithms may include special-case procedures that function to increase the speed or efficiency of problem solving. We conclude with a discussion of several more general issues relevant to the reported research.

Brain Damage, Chronic↗
PubMed1990

Relation of global ratings of functioning with behaviour and development in delayed and disturbed preschoolers.

Ratings on the Global Assessment Scale for Children (GASC) were assessed in relation to a battery of objective developmental and behavioural measures. Children aged three to six years (N = 55) attending a day treatment program for developmental delays, language disorders, and behavioural and emotional problems comprised the sample. A battery of tests was administered to the children. Parents and teachers completed standardized questionnaires to measure developmental, behavioural and emotional problems. The results indicated that the GASC score correlated significantly with child developmental level, impulse control, and with teacher ratings of social withdrawal. The GASC was unrelated to ratings of behavioural problems. Ratings on the GASC also were highly consistent over time. These results are discussed with respect to the strengths and limitations of using global ratings with preschool children.

Affective Symptoms↗
PubMed1979

Osteosarcoma complicating Paget's disease of the spine with neurologic complications.

An osteosarcoma with neurologic manifestations complicated Paget's disease of the lumbar spine in a 63-year-old man. Initially without demonstrable metastasis, the patient was treated by decompressive laminectomy followed by radiation and adjuvant chemotherapy (COMPADRI-1 regimen). While such treatment may not be curative, there are significant palliative benefits.

Diagnosis, Differential↗