Hannu Lauerma

Exploring the relations between depression, somatization, dissociation and alexithymia--overlapping or independent constructs?

Background: The aim of this study was to extend our knowledge of associations among the constructs of alexithymia, depression, somatization and dissociation. Sampling and Methods: 924 nonclinical subjects answered questions about depression (21-item Beck Depression Inventory), somatization (13-item somatization part of Symptom Check List-90), dissociation (28-item Dissociative Experiences Scale) and alexithymia (20-item Toronto Alexithymia Scale). In addition, a 12-item General Health Questionnaire (GHQ-12) was administered to detect psychiatric distress among subjects. Results: The results suggested that there was a significant clinical correlation between somatization, dissociation, depression and alexithymia (rho varied from 0.31 to 0.56). The principal component analysis revealed the presence of four components: depression, somatization, dissociation and alexithymia. The use of factor scores diminished the covariance between measures (rho varied from –0.10 to 0.01 between the factor scores). There was almost no correlation between the dissociation factor (rho = 0.06) and alexithymia factor (rho = 0.09) scores and general distress (GHQ-12). Conclusions: This study suggests that while somatization, dissociation, depression and alexithymia are distinct constructs, they correlate to a considerable extent. The use of factor analysis and factor scores should be considered to diminish covariance between the above constructs. Comparing results between factored and unfactored results may prove illuminating. As a case in point, the results suggest that the part of dissociation that coincides with other constructs (overlaps) is associated with distress, whereas the distinct part of dissociation (no shared covariance) is not associated with distress. The same applies to the alexithymia construct. Longitudinal studies are needed to show whether there is a trait such as a relatively stable dissociation component and also whether a separate state-dependent dissociation component exists that is associated with coincident distress, somatization and depression.

Seasonal affective disorders among rural Finns and Lapps

Saarijärvi S, Lauerma H, Helenius H, Saarilehto S. Seasonal affective disorders among rural Finns and Lapps.

The Finnish version of the Dissociative Experiences Scale-II (DES-II) and psychiatric distress

The confirmatory factor structure of the Finnish version of the Dissociative Experiences Scale II (DES-II) was exactly the same in the non-clinical population (n=924) as was found in the most recent study in the USA (with the original English version) and as suggested by the authors of the original version. The Finnish version of the DES-II has a Cronbachs alpha of 0.92, and there is a clear positive correlation (from 0.31 to 0.66) between all 28 items and the total score (P<0.001 for all items), indicating good internal consistency and reliability. We also investigated dissociative experiences and psychiatric distress with the DES-II and the General Health Questionnaire (GHQ-12). The increased proportion of pathological dissociation (DES-T) to non-pathological dissociation (DES-NP) was directly linked with increased distress. This finding is meaningful for the debate on the utility of the different DES-II scoring systems.

Visual distortions and dissociation

Visual distortions may be a frightening experience. They are often incorrectly diagnosed and easily dismissed. The causes of visual distortions are poorly understood. The aim of this study was to investigate the link between visual distortions and dissociative experiences in a nonclinical population. A total of 297 nonclinical volunteers completed the Dissociative Experience Scale and answered questions concerning visual distortions. Our study suggests that visual distortions are quite common and that there is a clear link between visual distortions and dissociative phenomena. Literature indicates that this may be caused by disturbances in brain lateralization. Bilateral language capacity may interfere with abilities usually associated with the nondominant hemisphere. Research efforts attempting to shed light on the above matter may benefit our knowledge for dissociative phenomena. An interdisciplinary approach is needed.

Effect of Visual Information on Postural Control in Patients With Schizophrenia

Lateralized motor and attentional abnormalities contribute to schizophrenia, but little is known about possible abnormalities in neural machinery involved in postural control. We examined postural stability of 22 patients with schizophrenia taking medication and 14 healthy control participants using computerized force platform posturography. The shift in the center point of pressure in the condition of eyes open versus eyes closed characterizes the effect of visual information on body posture. Closing the eyes had less of an effect on the center point of velocity (velocity sm/s) in the patients with schizophrenia than in the control group (median change, 36% vs. 70%, p = 0.0006). Change in the body position during eye closure tended to be directed rightwards in the control group but leftwards in the group with schizophrenia (p = 0.025). The results show that visual component had less dominance in the balance control of these patients with schizophrenia. The lateralized effect of visual information on posture was also impaired.

Recurrent CSPs after Transcranial Magnetic Stimulation of Motor Cortex in Restless Legs Syndrome

Aims. The aim of this study was to investigate the motor control and central silent period (CSP) in restless legs syndrome (RLS). Methods. Transcranial magnetic stimulation was focused on the dominant and nondominant hemispheric areas of motor cortex in six subjects with RLS and six controls. The responses were recorded on the contralateral abductor digiti minimi (ADM) and tibialis anterior (TA) muscles with intramuscular needle electrodes. Results. No significant differences were found in the motor conduction or central motor conduction time, in the latency, or in the duration of the CSPs between or within the groups, but multiple CSPs were observed in both groups. The number of the CSPs was significantly higher in both ADMs and in the dominant TA (P ≤ 0.01) in the RLS group compared to the controls. Conclusion. Descending motor pathways functioned correctly in both groups. The occurrence of the recurrent CSPs predominantly in the RLS group could be a sign of a change of function in the inhibitory control system. Further research is needed to clarify the role of the intramuscular recording technique and especially the role of the subcortical generators in the feedback regulation of the central nervous system in RLS.

Associations among Dissociative experiences, handedness, and demographic variables in a nonclinical population

Handedness is considered an indirect marker for bilateral language capacity in the brain. The Edinburgh Inventory for Handedness and the Dissociative Experiences Scale (DES) were administered to 297 nonclinical volunteers. Female sex, young age, and non-right handedness accounted for 24% of the total variance on the DES, including both pathological and nonpathological dissociative experiences. This is consistent with the hypothesis that cerebral lateralization indicating handedness is a predisposing factor for dissociative episodes especially in female subjects.

Psychopathic traits in a representative sample of Finnish male prisoners

Abstract Background: The psychopathic traits measured with the Hare Psychopathy Checklist-Revised (PCL-R) in a representative national prisoner sample have not been studied in Finland before. It has been unclear whether there could occur some national differences or whether the PCL-R can be used for assessing psychopathic traits in the Finnish forensic settings. Aims: Our aim was to study the distribution of psychopathic traits in the Finnish male prisoners as well as the correlations of these traits with DSM-IV disorders and to compare the sample with similar samples of Europe and America. Methods: 171 male prisoners representing all Finnish sentenced male offenders (about 3300) were studied using the PCL-R, SCID-I and SCID-II. Results: The results of the first Finnish study utilizing the PCL-R in a representative national sample of male prisoners were quite similar to the findings of the previous studies of male prisoners carried out in North America, the UK and Sweden. The scores of the interpersonal facet are lower in this sample than in the sample of North America. In total, 16.4% of the Finnish male prisoners can be diagnosed as having a psychopathic disorder. Conclusions: The PCL-R is a reliable and valid measure of the psychopathy construct of the Finnish male prisoners. The PCL-R is applicable to the Finnish offenders and it is a useful tool for assessing psychopathy in the Finnish criminal justice settings.

Knocking on prison’s door: a 10-fold rise in the number of psychotic prisoners in Finland during the years 2005–2016

Abstract Background: As in many European countries, Finnish psychiatric services experienced a rapid process of deinstitutionalization in the 1990s. In recent decades, the decrease in numbers of psychiatric hospital beds has in several countries been found to be linked with increasing criminality among severely mentally ill individuals. It has been concluded that deinstitutionalization could be the main reason for this development. Aim: To investigate whether the prevalence of severely mentally ill persons to prison is a growing trend also in Finland. Methods: We searched for the annual data in electronic case files of all prisoners about the ICD-10 diagnostic group of the most severe psychotic disorders. We also searched for the comorbid substance use disorders. Psychotic disorders due to substance abuse only were excluded from this study. Results: During the years 2005–2016, a rapid 10-fold increase in psychotic disorders has occurred in Finnish prisons. In 2016, 185 prisoners (5.9% of all Finnish prisoners) were diagnosed as having a psychotic disorder that was not induced by substance abuse. The causes of this dramatic change are unclear. Comorbid substance abuse disorders were detected in only 39.5% of these prisoners and therefore substance abuse can only partly explain the increasing criminality of the severely mentally ill persons. 80.5% of psychotic disorders were diagnosed in Psychiatric Hospital for prisoners and 19.5% in prison policlinic services. Conclusion: Trans-institutionalization has become a serious challenge for the Finnish criminal justice and mental health systems. Further studies are needed to detect the causes of this change. More specialized services for severely mentally ill persons are needed both in the community psychiatry and also inside the prison services.

Disrupted Central Inhibition after Transcranial Magnetic Stimulation of Motor Cortex in Schizophrenia with Long-Term Antipsychotic Treatment

Aims. Schizophrenia is a neuropsychiatric disorder associated with mental and motor disturbances. We aimed to investigate motor control, especially central silent period (CSP) in subjects with schizophrenia (n = 11) on long-term antipsychotic treatment compared to healthy controls (n = 9). Methods. Latency and duration of motor evoked potentials (MEPs) and CSPs were measured with the help of single pulse transcranial magnetic stimulation (TMS) and intramuscular electrodes. After stimulation of the dominant and nondominant motor cortex of abductor digiti minimi (ADM) and tibialis anterior (TA) muscle areas, respective responses were measured on the contralateral side. Results. MEPs did not differ significantly between the groups. Multiple CSPs were found predominantly in subjects with schizophrenia, which showed a higher number of CSPs in the dominant ADM and the longest summarized duration of CSPs in the nondominant ADM (P < 0.05) compared to controls. Conclusions. There were multiple CSPs predominantly in the upper extremities and in the dominant body side in subjects with schizophrenia. Behind multiple CSPs may lie an impaired regulation of excitatory or inhibitory neurotransmitter systems in central motor pathways. Further research is needed to clarify the role of the intramuscular recording methods and the effect of antipsychotics on the results.