Biomedical subjects

Rudolf Cohen

Publications and source records attributed to Rudolf Cohen.

7 recordsLinked to original sources

PubMed2006

The Brief Motor Scale (BMS) for the assessment of motor soft signs in schizophrenic psychoses and other psychiatric disorders.

Subtle motor impairment is an important aspect of neurological soft signs (NSS) which are frequently found in psychiatric patients-particularly schizophrenic patients. On the basis of data collected in previous studies using two different NSS scales, the most reliable and discriminative signs of motor impairment were identified to construct a brief 10-item rating scale. Subsequently, the new scale was applied to a sample of subacute patients with schizophrenic psychoses (N = 82) and healthy controls (N = 33). Factor analysis identified two factors which were labeled "motor coordination" and "motor sequencing". Both the total score and the subscores showed high internal consistency and test-retest reliability. There were highly significant group differences on the total score and the subscores as well as on each individual task. The scale has high sensitivity (84.1%) and specificity (87.9%) indicating that it may provide an effective instrument for the screening of subjects with neurodysfunction as well as for monitoring motor dysfunction in the clinical course of psychiatric disorders.

Adolescent↗

PubMed2006

Motoric neurological soft signs and psychopathological symptoms in schizophrenic psychoses.

Motoric neurological soft signs (NSS) were investigated by means of the Brief Motor Scale (BMS) in 82 inpatients with DSM-III-R schizophrenic psychoses. To address potential fluctuations of psychopathological symptoms and extrapyramidal side effects, patients were examined in the subacute state, twice at an interval of 14 days on the average. NSS were significantly correlated with severity of illness, lower social functioning, and negative symptoms. Modest, but significant correlations were found between NSS and extrapyramidal side effects as assessed on the Simpson-Angus Scale. Neither the neuroleptic dose prescribed to the patient, nor scores for tardive dyskinesia and akathisia were significantly correlated with NSS. Moreover, NSS scores did not significantly differ between patients receiving clozapine and conventional neuroleptics. Patients in whom psychopathological symptoms remained stable or improved over the clinical course showed a significant reduction of NSS scores. This finding did not apply to those patients in whom psychopathological symptoms deteriorated. Our findings demonstrate that NSS in schizophrenic psychoses are relatively independent of neuroleptic side effects, but they are associated with the severity and persistence of psychopathological symptoms and with poor social functioning.

Adolescent↗

PubMed2005

How do psychiatrists choose among different antipsychotics?

OBJECTIVE: We attempted to determine the decision rules psychiatrists use in the choice of antipsychotic drugs for inpatients with schizophrenia. METHODS: Interviews were conducted with 50 hospital psychiatrists in Southern Germany. Each physician was interviewed with respect to the reasons for his antipsychotic drug choice in the cases of three patients with a diagnosis of schizophrenia. Interviews were audiotaped and subsequently analyzed using a standardized coding scheme. RESULTS: The clinical decision rules identified are highly complex, with a mean of eight categories cited per patient. Categories named included the patient's past treatment response, side effects, intended route of administration and co-morbidities. Moreover, psychiatrists strongly take the patient's target symptoms and the assumed efficacy of certain compounds into account in their choice of medication. CONCLUSION: Psychiatrists' explanations for their antipsychotic drug choice seem for the most part reasonable and overlap substantially with drug-choice algorithms of clinical guidelines. However, psychiatrists additionally use indicators that--in their view--might predict treatment response. For these indicators, which are derived from personal experience, it is still unclear whether they are valid and simply have not yet been proven in clinical trials or whether they merely represent unfounded assumptions on the part of the doctors.

Adult↗

PubMed2005

Do patients with schizophrenia wish to be involved in decisions about their medical treatment?

OBJECTIVE: Little is known about the desire of patients with schizophrenia to be involved in medical decisions affecting their treatment. METHOD: The authors administered the Autonomy Preference Index to 122 inpatients with schizophrenia. In addition, the patients filled out the Drug Attitude Inventory. Sociodemographic data and Positive and Negative Syndrome Scale ratings were available for all patients. RESULTS: The patients expressed a desire for shared decision making that was slightly greater than that of primary care patients. Negative attitudes toward medical treatment and younger age were associated with a higher desire for participation. CONCLUSIONS: It is important to meet the participation needs of patients who are dissatisfied with their psychiatric treatment.

Adult↗

PubMed2003

Semantic categorization in the human brain: spatiotemporal dynamics revealed by magnetoencephalography.

We examined the cortical representation of semantic categorization using magnetic source imaging in a task that revealed both dissociations among superordinate categories and associations among different base-level concepts within these categories. Around 200 ms after stimulus onset, the spatiotemporal correlation of brain activity elicited by base-level concepts was greater within than across superordinate categories in the right temporal lobe. Unsupervised clustering of data showed similar categorization between 210 and 450 ms mainly in the left hemisphere. This pattern suggests that well-defined semantic categories are represented in spatially distinct, macroscopically separable neural networks, independent of physical stimulus properties. In contrast, a broader, task-required categorization (natural/man-made) was not evident in our data. The perceptual dynamics of the categorization process is initially evident in the extrastriate areas of the right hemisphere; this activation is followed by higher-level activity along the ventral processing stream, implicating primarily the left temporal lobe.

Adult↗

PubMed2002

Brain activity during syntactic and semantic processing--a magnetoencephalographic study.

Drawings of objects were presented in series of 54 each to 14 German speaking subjects with the tasks to indicate by button presses a) whether the grammatical gender of an object name was masculine ("der") or feminine ("die") and b) whether the depicted object was man-made or nature-made. The magnetoencephalogram (MEG) was recorded with a whole-head neuromagnetometer and task-specific patterns of brain activity were determined in the source space (Minimum Norm Estimates, MNE). A left-temporal focus of activity 150-275 ms after stimulus onset in the gender decision compared to the semantic classification task was discussed as indicating the retrieval of syntactic information, while a more expanded left hemispheric activity in the gender relative to the semantic task 300-625 ms after stimulus onset was discussed as indicating phonological encoding. A predominance of activity in the semantic task was observed over right fronto-central region 150-225 ms after stimulus-onset, suggesting that semantic and syntactic processes are prominent in this stage of lexical selection.

Adult↗

PubMed2002

Slow event-related brain activity of aphasic patients and controls in word comprehension and rhyming tasks.

Slow event-related potentials (ERP) were examined in healthy and aphasic subjects in two-stimulus designs comprising a word comprehension and a rhyming task. Aphasics, though selected to perform above chance level, made significantly more errors and responded more slowly than controls, although canonical correlations did not indicate a statistical relationship between performance measures and ERP amplitudes. A discriminant analysis of ERP amplitudes distinguished the groups for the slow wave (SW; 0.5-1.0 s post-S1 onset) in the word comprehension, for the SW and the initial contingent negative variation (iCNV; 1.0-2.0 s post-S1 onset) in the rhyming task. Similarly for both tasks, ERP topography showed left-anterior predominance of the negative SW and iCNV in controls, whereas participants with aphasia showed smaller anterior and larger left-posterior amplitudes. The centroparietal terminal CNV (tCNV; 1 s pre-S2) was smaller in participants with aphasia than in controls, but similar in topography. Results suggest left-anterior activation for those language processes that were presumably provoked in the present tasks, like lexical access, or phonological encoding. The pattern of participants with aphasia may indicate effects of language impairment and recovery, but also consequences of the brain damage.

Adult↗