R.A. Bornstein

Neuropsychological performance in children with tourette's syndrome

Neuropsychological performance was examined in a sample of 100 children between the ages of 6 and 18 years who met DSM-III-R criteria for Tourettes syndrome. Neuropsychological test scores were converted to age-corrected t scores based on published normative data. Ratings of Tourettes symptoms were also obtained. The mean IQ of the sample was approximately 100. Most of the subjects performed within normal limits, although approximately 20% obtained scores suggesting impairment on a summary neuropsychological performance measure. There were no differences attributable to medication effects. Later age at onset and the severity of complex tics were related to performance below normal levels on a number of neuropsychological measures. There was no specific evidence of frontal lobe dysfunction. The pattern of neuropsychological performance was virtually identical to a previously reported independent sample of patients. These data suggest a relatively characteristic pattern of neuropsychological performance abnormalities in a subgroup of patients with Tourettes syndrome. In general, most patients appear to perform within normal limits. Directions for future investigation are considered.

Neuropsychological deficit in schizophrenic subtypes: Paranoid, nonparanoid, and schizoaffective subgroups

Schizophrenic patients were carefully diagnosed and screened for a history of neurological disorders. Diagnosis and subtyping was based on DSM-III-R criteria, using the Structured Clinical Interview for DSM-III-R, which was administered by trained interviewers and confirmed by a research psychiatrist. The schizophrenic patients were compared with an age-matched control group on an extensive battery of neuropsychological measures. The undifferentiated/disorganized schizophrenic patients were consistently the most impaired on a broad range of tasks. When the effect of symptom severity and drug level were statistically controlled (analysis of covariance), however, the magnitude and number of differences were substantially reduced. The perseverative error score from the Wisconsin Card Sort Test showed the greatest difference between the groups. However, the strongest and most consistent effects were observed in relation to symptom ratings. These data indicate the importance of controlling for medication and symptom severity, and suggest that current diagnostic classifications may not be the most useful factors for studies of the cognitive correlates of schizophrenia.

PHENYLETHYLAMINERGIC MECHANISMS IN ATTENTION-DEFICIT DISORDER

Urinary excretion (24-hr) of beta-phenylethylamine (PEA), phenylacetic acid (PAA), phenylalanine (Phe), and p-tyrosine (Tyr), and plasma levels of PAA, Phe, and Tyr were examined in 18 normal children and 26 children diagnosed as having attention-deficit hyperactivity disorder (ADHD). The results indicated that urinary excretion (expressed per g of creatinine) of free and total PEA was significantly lower in the ADHD patients, and plasma levels of Phe and Tyr were also decreased in the ADHD subjects compared with the normal controls.

Neuropsychological performance in adults with Tourette's syndrome

Neuropsychological performance was examined in a sample of 36 adults who met DSM-III-R criteria for Tourettes syndrome (TS), confirmed by a psychiatrist or a neurologist. All subjects were administered an extensive battery of psychological and neuropsychological tests as well as symptom rating scales. The mean performance on most tests was within normal limits, and the patients and controls did not differ on a summary measure of neuropsychological performance. However, apparently 20% of the TS subjects had mild abnormalities on a summary measure of neuropsychological performance. These data are consistent with recent reports of generally normal performance in children with TS. Poor performance on several tasks was related to later age at symptom onset. The results were discussed with regard to the nature of the sample and directions for future research.Neuropsychological performance was examined in a sample of 36 adults who met DSM-III-R criteria for Tourettes syndrome (TS), confirmed by a psychiatrist or a neurologist. All subjects were administered an extensive battery of psychological and neuropsychological tests as well as symptom rating scales. The mean performance on most tests was within normal limits, and the patients and controls did not differ on a summary measure of neuropsychological performance. However, apparently 20% of the TS subjects had mild abnormalities on a summary measure of neuropsychological performance. These data are consistent with recent reports of generally normal performance in children with TS. Poor performance on several tasks was related to later age at symptom onset. The results were discussed with regard to the nature of the sample and directions for future research.

Tourette syndrome and neuropsychological performance

This study examined performance on a battery of neuropsychological tests in a sample of 28 patients with Tourettes syndrome (TS). Test scores were converted to age‐corrected T‐scores to control for the effect of age on test performance. The frequency of abnormal test performances was variable, but more frequent on motor and sensory tasks. Symptom severity as measured by the Tourette Syndrome Global Scale was inversely related to neuropsychological performance. In general, neuropsychological performance was mildly below average. The pattern of performance was similar to previous studies of TS patients.

Classification rates obtained with “standard” cut-off scores on selected neuropsychological measures

Examined in a normal sample (N = 365) the number of subjects was classified as impaired on several commonly used neuropsychological tests (Seashore Rhythm Test, Trail Making Test, Finger Tapping Test, and Grooved Pegboard Test) in reference to conventional cut-off scores. The sample was stratified on the basis of age, sex, and education. For the sample as a whole, the percentage of subjects classified as impaired ranged from 15.6 to 80. In some subgroups on some tests, the percentage so classified was 100. The data were discussed in relation to the need to adjust conventional cut-off scores for the influence of subject variables. In addition, cross-cultural differences on some tests suggested the need for local or national normative studies.

Third-ventricle enlargement and neuropsychological deficit in schizophrenia☆

Cerebral ventricular enlargement is present in a substantial subgroup of schizophrenic patients. Most, but not all studies examining neuropsychological performance and ventricular size in schizophrenics show more severe cognitive impairment in those patients with greatest ventricular enlargement. Inconsistencies in this literature have been attributed to different neuroimaging techniques, variation in patient characteristics across studies, and the variety of neuropsychological batteries used. In the present study, schizophrenic patients (n = 49 men, n = 23 women) and normal controls (n = 13 men, n = 18 women) underwent magnetic resonance (MR) imaging of the brain and extensive neuropsychological testing including measures of frontal and temporal lobe function. A complete coronal set of MR images was used to calculate volumetric estimates of lateral and third cerebral ventricles. Highly significant associations were found between cognitive deficits and third-ventricle volume, with measures of frontal functioning, attention, and concentration showing the most robust correlations. In contrast, neuropsychological performance was not highly associated with lateral ventricular size. These findings further support the pathophysiological relevance of ventricular enlargement in schizophrenia. More specifically, third, but not lateral, ventricular enlargement was associated with greater cognitive disturbance in this sample. Results are consistent with pathological involvement of periventricular diencephalic structures resulting in dysfunctional frontal and limbic processing in a subgroup of patients.

Plasma amino acids in attention deficit disorder

This study examines plasma amino acids in a group of 28 patients meeting DSM-III criteria for attention deficit disorder (ADD) and 20 control subjects. Compared with controls, the ADD subjects had significantly lower levels of phenylalanine, tyrosine, tryptophan, histidine, and isoleucine. These data suggest a general deficit in amino acid transport, absorption, or both.

Urinary amines in Tourette's syndrome patients with and without phenylethylamine abnormality

Previous data indicated a subgroup of Tourettes syndrome patients with a beta-phenylethylamine (PEA) level that was lower than all subjects in a control group matched for age and education. The current study compared the subgroups of Tourettes syndrome patients (n = 28) from the previous study with 20 control subjects in regard to other amines and metabolites. Patients with low levels of PEA were also found to have lower levels of 3-methoxy-4-hydroxy-phenylglycol, normetanephrine, serotonin, m-tyramine, and p-tyramine. There was also some evidence of dopaminergic abnormalities in the low-PEA subgroup. These data provide suggest a role of PEA in the pathophysiology of some patients with Tourettes syndrome. This effect may be mediated through other neurotransmitter systems.

Urinary indoleamines in Tourette syndrome patients with obsessive-compulsive characteristics.

Tourette syndrome patients with high levels of obsessive-compulsive symptoms were compared with patients without these symptoms on urinary measures of serotonin and its major metabolite, 5-hydroxyindoleacetic acid (5HIAA). Both groups were compared with normal controls, and it was hypothesized that patients with obsessive-compulsive symptoms would have lower levels of serotonin. Both groups of Tourette syndrome patients had lower levels than controls, but there was no difference between them. Obsessive symptoms were related to higher levels of 5HIAA and to a higher turnover of serotonin.