Delusional Parasitosis

Abstract: In order to examine the clinical characteristics of delusional parasitosis in a large sample, we previously analyzed 102 cases reported in Japan. In this article, these results are shown briefly, and psychopathological symptoms and nosological classifications are discussed.
In our study, 53 cases were classified in to pure type excluding endogenous psychoses, induced psychosis and somatically based psychoses. Two thirds of the pure type cases had visual experiences. These cases involved both hallucinatory and delusional factors, and symptoms considered delusional perception or bodily hallucinations "being made" by parasites were included in these experiences. Although these symptoms are thought to be specific to schizophrenia, some biological findings were often present. Furthermore, the facts concerning sex difference, age at onset, and no personality changes resembled late-onset paraphrenia, that is, a type of atypical psychoses. Therefore, both psychopathological and biological studies should be carried out continuously from now on.     

Delusional loving

Erotomania is reexamined by an in-depth study of eight patients. There appear to be two main varieties: the phantom lover syndrome, or fixed delusion elaborated around a person who does not exist, and erotomania proper, a recurrent tendency to believe that one is loved by a powerful, prominent man.     

Delusional misidentification

The purpose of the present study was to investigate differences in brain activation with functional magnetic resonance imaging (fMRI) during imagery of painful and non-painful ‘finger movements’ and ‘hand positioning’ in a subject with an amputated arm. The subject was a right-handed man in his mid-thirties who lost his right arm just above the elbow in a car-train accident. MRI was performed with a 1.5 T Siemens Vision Plus scanner. The basic design involved four conditions: imagining ‘painful finger movements’, ‘non-painful finger movements’, ‘painful hand positioning’, ‘non-painful hand positioning’. Imagery of finger movements uniquely activated the contralateral primary motor cortex which contains the classic ‘hand area’. The lateral part of the anterior cerebellar lobe was also activated during imagery of finger movements. Imagery of pain uniquely activated the somatosensory area, and areas in the left insula and bilaterally in the ventral posterior lateral nucleus of the thalamus. It is suggested that the insula and thalamus may involve neuronal pathways that are critical for mental processing of pain-related experiences, which may relate to a better understanding of the neurobiology of phantom limb pain.     

Delusional Depression and Suicide

Abstract: During the 12-year period of retrospective observation, 38 cases of 93 major depressive inpatients were delusional and the remainders were nondelusional. We evaluated the differences on several variables, especially about suicide, between the two groups. The mean age at the onset of illness of delusional depressive patients was higher than that of nondelusional ones. The incidence of psychomotor retardation was lower in the former group than in the latter. The frequency of suicidal ideation and suicidal attempts were higher in the former group than the latter. The suicidal methods in the delusional depressives tended to be more active and violent than those in nondelusional depressives and were supposed to have a twofold mortality than those in the nondelusional ones. We discussed this high rate of suicides of delusional depression from the viewpoint of disinhibition of psychomotor retardation, chronicity, partial affinity of delusional depressives to schizophrenics and neuroendocrinological perspective.     

Delusional depression and suicide

After a short survey of the relevant literature, the authors discuss the significance of delusional depression symptoms for suicidality, whereby they do not regard such symptoms alone as a sufficient condition for classifying a delusional patient as suicidal. In a comparison of delusional depressed patients with a non-delusional control group (matched pairs), the former were adjudged to be significantly less suicidal than the control group and did not differ from the control group in regard to suicide frequency.     

Delusional misidentification.

The Capgras syndrome and other forms of delusional misidentification may be encountered frequently in neuropsychiatric settings. DMS can occur in the presence of idiopathic psychiatric illness, in diffuse brain illness such as dementia, and in focal neurologic disease. In patients who have focal lesions, there is evidence that right hemisphere damage is necessary for the production of DMS. Although DMS is associated with a pattern of neuropsychologic impairments in the domains of memory, perception, and executive function, these impairments alone do not account for the selectivity and delusional nature of DMS. Therefore, other factors such as premorbid psychopathology, motivation, and loss of ego functions may be important in determining which vulnerable patients develop DMS and which do not.     

The prevalence of cyclothymia in borderline personality disorder

Sixty patients with personality disorders were evaluated by several different diagnostic instruments to determine the prevalence of cyclothymia in borderline personality disorder (BPD) and in other personality disorders (OPD). Cyclothymia occurred more frequently in BPD than in OPD, regardless of which diagnostic system was used. In contrast, the prevalence of major, minor, and intermittent depression, hypomania, and bipolar disorder was not significantly different in BPD as compared with OPD. Cyclothymic borderlines and noncyclothymic borderlines could not be distinguished on behavioral or functional measures. These results have implications for the diagnostic validity of both BPD and cyclothymia.     

Delusional theme, sex and age

In a retrospective study of 865 delusional syndromes, connections were investigated between delusional themes and the sex of patients, and the ages in which these themes extensively occurred. According to previous reports, the results of this investigation indicated that differences exist between the ages of manifestation regarding the themes of hypochondria, persecution, love and jealously. Furthermore, differences could be observed between males and females in relation to the frequency of choice of particular themes, as well as the age of occurrence. Based on psychological studies concerned with the content's dependence on motives we conclude that the age distribution of delusional themes corresponds to the main existential concerns in different life periods.