Kaoru Sakamoto

Association between novelty seeking and dopamine receptor D4 (DRD4) exon III polymorphism in Japanese subjects

In this study, we investigated the association between dopamine receptor D4 (DRD4) exon III polymorphism and novelty seeking in 69 Japanese women. The group of subjects with long allele (> or =5 repeats) exhibited significantly elevated novelty seeking scores in comparison with subjects lacking the long allele. By contrast, the scores for harm avoidance, reward dependence, and persistence were statistically indistinguishable in the two group of subjects. With regard to the subscales of novelty seeking, the scores for exploratory excitability and extravagance were significantly higher in subjects with the long allele than in subjects lacking the long allele. However, no significant associations with impulsiveness or disorderliness were recognized. Our results suggest that although long alleles of the polymorphic exon III repeats are low in the Japanese population, there is an association between long alleles of DRD4 exon III polymorphism and novelty seeking.

Insight and clinical correlates in schizophrenia

It is not clear to what extent poor insight is inherent in schizophrenic psychopathology or is related to clinical factors. It is clinically important to elucidate this point to know how some insight remains intact in schizophrenia. Sixty-three ICD-10 schizophrenics were recruited. Insight was measured by Davids three-dimensional scale, which deals with the awareness of the need for treatment, of the illness, and of psychotic experiences. Clinical factors that may influence insight were grouped into objective psychopathology, subjective experience, and treatment settings, according to the normal development of insight starting from objective illness, through subjective perception of it, to seeking treatment. Psychopathology was measured by the Brief Psychiatric Rating Scale (BPRS) and the Scale for the Assessment of Negative Symptoms (SANS), and the subjective experience was measured by a checklist of our own. Positive symptoms, especially disordered thought, hallucinations, and delusions, had a modest inverse correlation with awareness of illness and of psychotic experiences, but these were not correlated with alogia or other negative symptoms. Later age at the first onset was significantly correlated with poor awareness of psychotic experience, but no correlation of subjective experience with insight emerged. Awareness of the need for treatment was significantly higher in outpatient than in inpatient groups, and was not correlated with any other variables. Poor awareness of illness and of psychotic experience seems to be a trait of the acute rather than the chronic psychopathology of schizophrenia. Poor awareness of psychotic experience was related to later onset. Awareness of the need for treatment seems to improve, even in the absence of awareness of illness or of psychotic experience, in outpatient settings--the effects of social interaction may be relevant to this.

Subjective experience and related symptoms in schizophrenia

We had previously extracted two types of subjective experience of schizophrenia (SES); first, a feeling of inadequacy in stream of speech, thought, and action, associated with a distorted sense of self, and second, a feeling that excessive thoughts are filling and sticking to ones head, causing negative affective burden such as misery and oppression. This study tried to validate their content using conventional symptom clusters as external validators. Subjects were 63 patients from two hospitals in Tokyo meeting ICD-10 criteria for schizophrenia. Positive, negative, and depressive psychopathology were measured by the Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of the Negative Symptoms (SANS), and Hamiltons Depression Scale (HDS). The two types of SES were measured by an original scale. The first type of SES correlated significantly with the negative symptoms of alogia, avolition, and attention, whereas the second correlated with positive and depressive symptoms. To analyze how schizophrenia is experienced by patients, qualitative and comprehensive descriptions, such as indicated by our subjective factors, will be useful.

Familial transmission of seasonal changes in sleep and eating function in the general population

Both genetic and environmental factors may be involved in the development of the increased sleep and appetite/body weight during winter, which are observed in seasonal affective disorder (SAD) as well as in normal variants of behavior in the general population. Decreases of these psychosomatic functions are also observed during summer, although the change may be less apparent than the winter changes. We studied familial correlation of these seasonal changes in 129 small Japanese families of the general population, using the Seasonality Pattern Assessment Questionnaire (SPAQ). No association was observed between the child and biological parents in the changes of sleep length or appetite/body weight during winter or summer. In contrast, significant spouse correlations were found in the changes of sleep and eating function during winter as well as during summer. This may indicate a role of shared environmental factors in the development of the seasonal patterns. The present results are preliminary and further studies are recommended.

Long‐Term Course of Seasonal Affective Disorders: A Preliminary Report

In recent years, increasing interest has been centered on seasonal affective disorder (SAD), leading many researchers to investigate various aspects of SAD. To our knowledge, however, no systematic study on the long-term course of SAD has been reported. Nevertheless, there has been no clinical confirmation of the stability of this condition over a long period of time. Therefore, in this paper we report our observations of the long-term courses of patients with SAD. Our first purpose in this study was to determine whether a patient undergoes a switch from SAD to nonseasonal affective disorder (NONSAD), and vice versa, and if so, which factors would be associated with such a switch in individual cases.

Fifty Young Women's Seasonal Changes in Mood and Behavior in Tokyo

Since the Description of Seasonal Affective Disorder (SAD)4 the interest in seasonal influences on affective illness has increased. On the other hand, seasonal changes in mood and behavior in the normal population have been recognized well since ancient times but there have been only a few studies.l Seasonality of individuals have to be observed more concretely nowadays because not only for the request of the epidemiological investigation{, the proportion of patients with SAD in a population, but also to elucidate the mechanism of onset of SAD. Methods