Traumatic stress, dissociation, and limbic irritability in patients with unipolar depression being treated with SSRIs.

Recent evidence suggests that stressful experiences may be related to deficits in inhibitory functions and temporo-limbic epileptic-like activity. The latter may produce psychosensory seizure-like symptoms that may also appear in nonepileptic conditions. This study assesses whether the increased presence of the seizure-like symptoms in 113 unipolar depressive patients treated with SSRIs is associated with significantly more severe symptoms of depression, traumatic stress, and dissociation in comparison with 86 healthy controls. Results indicate that seizure-like symptoms in depressive patients have significant association with depression, symptoms of dissociation, and traumatic stress. This association suggests that processess generating seizure-like symptoms may be related to symptoms of depression, traumatic stress, and dissociation.

Dissociation, cognitive conflict and nonlinear patterns of heart rate dynamics in patients with unipolar depression.

Recent findings in cognitive neuroscience indicate that activation of anterior cingulate cortex (ACC) is related to detecting cognitive conflict. Conflict related ACC activation elicits responses in central autonomic network which can be assessed by psychophysiological measures such as heart rate variability (i.e. beat to beat R-R intervals--RRI). Recent findings in neuroscience also suggest that cognitive conflict is related to specific nonlinear chaotic changes of the signal generated by the neural systems. The present study used Stroop word-colour test as an experimental approach to the study of cognitive conflict in connection with RRI measurement, psychometric measurement of dissociation (DES) and calculation of largest Lyapunov exponents in nonlinear data analysis of RRI time series in 40 patients with unipolar depression and 35 healthy controls. Significant correlation 0.58 (p<0.01) between largest Lyapunov exponents and DES found in depressive patients indicate that cognitive conflict related neural interference during conflicting Stroop task is closely related to dissociative processes. These results present first supportive evidence that degree of chaos could be related to dissociation.

Dissociative symptoms and neuroendocrine dysregulation in depression.

BACKGROUND: Dissociative symptoms are traditionally attributed to psychological stressors that produce dissociated memories related to stressful life events. Dissociative disorders and dissociative symptoms including psychogenic amnesia, fugue, dissociative identity-disorder, depersonalization, derealization and other symptoms or syndromes have been reported as an epidemic psychiatric condition that may be coexistent with various psychiatric diagnoses such as depression, schizophrenia, borderline personality disorder or anxiety disorders. According to recent findings also the somatic components of dissociation may occur and influence brain, autonomic and neuroendocrine functions. At this time there are only few studies examining neuroendocrine response related to dissociative symptoms that suggest significant dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis. The aim of the present study is to perform examination of HPA axis functioning indexed by basal cortisol and prolactin and test their relationship to psychic and somatoform dissociative symptoms. MATERIAL/METHODS: Basal cortisol and prolactin and psychic and somatoform dissociative symptoms were assessed in 40 consecutive inpatients with diagnosis of unipolar depression mean age 43.37 (SD=12.21). RESULTS: The results show that prolactin and cortisol as indices of HPA axis functioning manifest significant relationship to dissociative symptoms. Main results represent highly significant correlations obtained by simple regression between psychic dissociative symptoms (DES) and serum prolactin (R=0.55, p=0.00027), and between somatoform dissociation (SDQ-20) and serum cortisol (R=-0.38, p=0.015). CONCLUSIONS: These results indicate relationship between HPA-axis reactivity and dissociative symptoms in unipolar depressive patients that could reflect passive coping behavior and disengagement.

Depression, cortisol and somatoform dissociative symptoms.

OBJECTIVE: According to recent findings neuroendocrine response related to dissociative symptoms is related to dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis but HPA axis functioning as related to dissociation is only partially understood. METHOD: With the aim to test the relationship between basal serum cortisol and dissociative symptoms measured as somatoform and psychic dissociation we performed clinical testing and biochemical analysis in 30 inpatients with diagnosis of unipolar depression (mean age 41.46, SD=13.68). RESULTS: The results show that cortisol as an index of HPA axis functioning manifests significant relationship to somatoform dissociative symptoms (r=-0.40; p=0.014). CONCLUSIONS: The result indicates relationship between HPA-axis reactivity and somatoform dissociative symptoms in unipolar depressive patients and suggests that somatoform dissociation presents a defense mechanism related to a passive coping response.

Psychobiology of dissociation and its clinical assessment.

OBJECTIVE: Dissociation is often defined as partial or total disconnection between memories of the past, awareness of identity and of immediate sensations, and control of bodily movements, often resulting from traumatic experiences, intolerable problems, or disturbed relationships. This type of reaction to a psychological and/or physical trauma has often various neurobiological consequences and its clinical assessment has received enormous interest in recent psychological and neuroscience research. METHODS: Psychometric parameters of the Czech version of the Dissociative Experiences Scale were tested from the viewpoints of internal consistency, validity and factor structure, using data from a sample of n=783 adults, divided into three groups (epilepsy n=243, depression n=357, norm n=183), average age 39 years, SD=13.5. RESULTS: Findings of this study demonstrated that reliability, validity and factor structure of the Czech version of the Dissociative Experiences Scale correspond to those of the original English version. CONCLUSIONS: The Czech version of the questionnaire may be considered a suitable tool for estimating subjectively experienced dissociative symptoms.

Depression, prolactin and dissociated mind.

OBJECTIVES: Usual neuroendocrinological manifestation of traumatic stress and dissociation is dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis. The aim of the present study is to perform examination of HPA axis as indexed by basal serum prolactin and test its relationship to dissociative symptoms and symptoms of traumatic stress. PATIENTS AND METHODS: 25 inpatients treated at the university hospital with diagnosis of unipolar depression mean age 41.23 (SD=11.53) were assessed using psychometric measures of dissociation (DES) and traumatic symptoms (TSC-40), and using standard biochemical analytical methods basal serum prolactin levels were investigated. RESULTS: Data show that prolactin manifests significant relationship to dissociative symptoms (r=0.52, p=0.004). Significant correlation was not found between prolactin and traumatic symptoms measured by TSC-40 (r=0.31, p=0.07). CONCLUSIONS: The present data suggest that serum prolactin levels in unipolar depressive patients are related to dissociative symptoms that is likely caused by passive coping mechanisms leading to dissociation.

Traumatic dissociation, epileptic-like phenomena, and schizophrenia.

OBJECTIVES: According to recent evidence, trauma and stress are important etiological factors in pathogenesis of schizophrenia. However, the hypothetical influence of traumatic stress on epileptic-like (or kindling) phenomena in schizophrenia is at this time unclear. METHODS: In order to discover the influence of trauma, 82 patients with a diagnosis of paranoid schizophrenia and 50 healthy controls were assessed for symptoms of dissociation, traumatic stress and psycho-sensory symptoms of epileptic origin. RESULTS: We have found significant traumatization and dissociation in patients who met the cut-off score for psychosensory epileptic-like symptoms and also significant correlations among these measures have been found. CONCLUSIONS: These data suggest a certain role of epileptic-like phenomena in dissociative states in schizophrenia and are in accordance with rare intracranial EEG findings which suggest a certain role of epileptiform events in schizophrenia.

Subclinical epileptiform process in patients with unipolar depression and its indirect psychophysiological manifestations.

BACKGROUND: According to recent clinical findings epileptiform activity in temporolimbic structures may cause depressive and other psychiatric symptoms that may occur independently of any seizure in patient's history. In addition in these patients subclinical seizure-like activity with indirect clinical manifestations likely may occur in a form of various forms of cognitive, affective, memory, sensory, behavioral and somatic symptoms (the so-called complex partial seizure-like symptoms). A typical characteristic of epileptiform changes is increased neural synchrony related to spreading of epileptiform activity between hemispheres even in subclinical conditions i.e. without seizures. These findings suggest a hypothesis that measures reflecting a level of synchronization and information transfer between hemispheres could reflect spreading of epileptiform activity and might be related to complex partial seizure-like symptoms. METHODS AND FINDINGS: Suitable data for such analysis may provide various physiological signals reflecting brain laterality, as for example bilateral electrodermal activity (EDA) that is closely related to limbic modulation influences. With this purpose we have performed measurement and analysis of bilateral EDA and compared the results with psychometric measures of complex partial seizure-like symptoms, depression and actually experienced stress in 44 patients with unipolar depression and 35 healthy controls. The results in unipolar depressive patients show that during rest conditions the patients with higher level of complex partial seizure like symptoms (CPSI) display increased level of EDA transinformation (PTI) calculated between left and right EDA records (Spearman correlation between CPSI and PTI is r = 0.43, p = 0.004). CONCLUSIONS: The result may present potentially useful clinical finding suggesting that increased EDA transinformation (PTI) could indirectly indicate increased neural synchrony as a possible indicator of epileptiform activity in unipolar depressive patients treated by serotoninergic antidepresants.

Epileptiform activity in alcohol dependent patients and possibilities of its indirect measurement.

BACKGROUND: Alcohol dependence during withdrawal and also in abstinent period in many cases is related to reduced inhibitory functions and kindling that may appear in the form of psychosensory symptoms similar to temporal lobe epilepsy frequently in conditions of normal EEG and without seizures. Because temporal lobe epileptic activity tend to spread between hemispheres, it is possible to suppose that measures reflecting interhemispheric information transfer such as electrodermal activity (EDA) might be related to the psychosensory symptoms. METHODS AND FINDINGS: We have performed measurement of bilateral EDA, psychosensory symptoms (LSCL-33) and alcohol craving (ACQ) in 34 alcohol dependent patients and 32 healthy controls. The results in alcohol dependent patients show that during rest conditions the psychosensory symptoms (LSCL-33) are related to EDA transinformation (PTI) between left and right EDA records (Spearman r = 0.44, p<0.01). CONCLUSIONS: The result may present potentially useful clinical finding suggesting a possibility to indirectly assess epileptiform changes in alcohol dependent patients.

Depression, traumatic stress and interleukin-6.

BACKGROUND: Recent evidence indicates that various types of interactions between nervous and immune system are important in pathogenesis of depression. These findings show that a significant role in developing depression play pro-inflammatory cytokines that may mediate its psychological, and neurobiological manifestations. Great importance among these cytokine molecules plays interleukin-6 (IL-6). There is growing evidence that this inflammatory process related to depression may be influenced by psychological stress as well as organic inflammatory conditions. These findings suggest that specific influences related to traumatic stress and dissociation could be found in close relationship to increased level of cytokine IL-6. METHODS: In the present study we have performed psychometric measurement of depression (BDI-II), traumatic stress symptoms (TSC-40) and dissociation (DES, SDQ-20), and immunochemical measure of serum IL-6 in 40 inpatients with unipolar depression (mean age 42.3+/-6.8). RESULTS: The results show that IL-6 is significantly correlated to BDI-II (Spearman R=0.47, p<0.01), TSC-40 (Spearman R=0.32, p<0.05), SDQ-20 (Spearman R=0.34, p<0.05) but not to DES (Spearman R=0.25, p=0.11). CONCLUSION: The findings of the present study indicate that increased level of IL-6 in depression could be directly related to symptoms of traumatic stress and somatoform dissociation.

Alcohol craving, limbic irritability, and stress.

BACKGROUND: Recent findings indicate that craving during alcohol withdrawal, also in abstinent patients, can relate to kindling phenomena caused by sensitization in temporo-limbic structures. Because limbic structures are involved in stress, anxiety, and emotional processing, kindling and temporolimbic seizure-like activity are also closely related to various psychiatric symptoms frequently presented without seizure disorders. Recent findings also show that these seizure-like processes are related to limbic irritability, which may also be significantly influenced by stressful life events. MATERIAL/METHODS: The hypothesis tested in the present study is that limbic irritability could be closely related to craving symptoms. Therefore, limbic irritability and craving were assessed using psychometric measures in 40 alcohol-dependent patients and the results were compared with those of 40 healthy controls. RESULTS: Statistical analysis showed highly significant correlation (r=0.75, p<0.0000001) between limbic irritability (LSCL-33) and craving (ACQ-R) and highly increased limbic irritability scores in the patients compared with the healthy controls. CONCLUSIONS: The results indicate that craving symptoms are related to the kindling process presented in the form of cognitive, affective, sensory, somatic, behavioral, and memory symptoms linked to limbic irritability and temporo-limbic seizure-like activity.