Several studies have found that the reaction time of schizophrenia patients is longer when successive imperative stimuli are of different modality (e.g., light followed by sound) than when they are identical (e.g., sound followed by sound). This effect is called the modality-shift effect. In this study, the reaction times of 175 persons were analyzed: 54 schizophrenia patients, 33 patients with mood disorders, 13 alcoholics, 17 patients with rheumatoid arthritis, 13 patients with internal diseases, and 45 normal controls. The results indicated that a shift from light to sound stimuli lengthened the reaction time for schizophrenia patients considerably more than for alcoholics, patients with rheumatoid arthritis, patients with internal diseases, or normal controls. No difference was found between the reaction times of schizophrenia patients and patients with mood disorders.

The haemoglobin percentage fell to 26% (3.8 g.%) and the total leucocyte count to 10,600. Death occurred on July 20. Relevant Necropsy Findings.-The skin and all organs were pale, with many petechial haemorrhages. Several tough, pale nodules were present in the scalp, and there was a large haematoma on the extensor surface of the right forearm. The lymph nodes were all enlarged and pale. The spleen was enlarged, weighing 26 oz. (737 g.). On section it was red, soft, and coarsely granular. The liver weighed 92 oz. (2,608 g.), and was pale and firm on section. The right ankle-joint was opened. The synovial membrane, synovial fluid, and articular cartilage looked normal. Report on Histology.-"Sections of liver, spleen, lymph node, scalp nodule, skin haematoma, kidney, and small intestine show, in greater or less degree, infiltration by immature leukaemic cells. A portion of the synovial membrane of the left ankle shows infiltration by leukaemic stem cells. The cells have round or ovoid vesicular nuclei

In the Lancet in 1945 Findlay et al. gave a brief account of their experiences with a complement fixation in hepatitis with liver extract as the antigen. For the extract they made use of a liver removed (immediately after death) from a case of rapid acute hepatitis. With this antigen they found complement fixation in patients with >>infective hepatitis< and hepatitis occurring after vaccination for yellow fever. These results were so important that we decided to make a similar test at the first opportunity.In June 1945 an occasion presented itself, a patient having died from acute yellow atrophy of the liver. With the liver from this patient as the basis for our investigation we prepared an extract according to the same method as that employed by Findlay et al. (Bedson & Bland). This liver extract was then employed as the antigen in complement fixation with sera from a number of liver diseases. We found a positive reaction in several diseases in which damage to liver cells is presumable (acute hepatitis, chronic hepatitis and obstructive icterus of long duration). We furthermore found that normal liver from people dying from the results of accidents and from diseases not affecting the liver could also be employed as the antigen. These experiments on the whole were concluded in November 1945.

Our data support newer theories about underlying pathophysiological mechanisms and observable behavioural phenomena occurring across the different diagnostic categories, thereby supporting a dimensional approach in the diagnosis and clinical management.

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Introduction:The effect of a shift of sensory modality on the serial reaction times of patients with schizophrenia was first reported in 1961. Zubin & Spring (1977) argued that the modality shift effect (MSE) might be a vulnerability marker for schizophrenia. A MSE has, however, also been observed in patients with depression, brain damage, alcoholism etc.Objectives:To examine if patients with schizophrenia can be differentated from patients with mood disorder on the basis of the MSE to light and tone stimuli.Aims:To evaluate if MSE measures could be useful in the diagnostic process.Methods:58 patients with schizophrenia, 55 patients with mood disorder, and 30 healthy controls participated in a computerbased reaction time experiment. The stimuli were short visual and auditory signals presented in a randomized sequence. Participants were instructed to press a button each time they saw or heard a signal.Results:The MSE to both light and sound stimuli of the patients with schizophrenia and mood disorder was significantly longer than the control group’s. There was no significant difference in the patient groups’ MSE to light stimuli; but patients with schizophrenia had a significantly longer MSE to tone stimuli than patients with mood disorder. No clear or consistent differences were observed when comparing subgroups of schizophrenia patients with positive, mixed, and negative symptoms, and mood disorder patients in manic, neutral, and depressive phases.Conclusion:The MSE to visual and auditory stimuli is not specific for schizophrenia as it can also be observed in mood disorder.

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Introduction:In experimental psychopathology there is a long tradition of reaction time studies. Especially in schizophrenia there has reliably been observed deficits in attention and reaction time.Objectives:To examine if patients with schizophrenia can be differentiated from patients with mood disorder on the basis of their reaction time patterns.Aims:To evaluate if reaction time measures might be useful in the diagnostic process.Methods:58 patients with schizophrenia, 55 patients with mood disorder, and 30 healthy controls participated in a computerbased reaction time experiment. The stimuli were short visual and auditory stimuli presented in a randomized sequence. The subjects were instructed to press a button each time they saw or heard a signal from the computer.Results:The reaction times of the patients with schizophrenia and mood disorder to both light and sound stimuli were significantly slower than those of the control group. Furthermore, the patient groups’ reaction times were significantly less stable than those of the control group, and they made significantly more errrors. However, no significant differences in reaction times, stability of reaction times, and number of errors were found between the two patient groups. No clear or consistent differences were observed when comparing the reaction time patterns of subgroups of schizophrenia patients with positive, mixed and negative symptoms, and mood disorder patients in manic and depressive phases.Conclusion:On the basis of simple reaction measures it is not possible to differentiate between patients with schizophrenia and mood disorder.