Intraindividual Characterization of the Sleep Spindle Variability in Healthy Subjects

Spatial and frequency characterization of sleep spindles have been extensively addressed using M/EEG or fMRI recordings. However, its intraindividual variability across time has not been addressed. Here we propose to assess the intraindividual variability of sleep spindles in a time-resolved way by means of a trial-to-trial-variability (TTV) measure. For that purpose, the EEG of 26 healthy subjects were recorded overnight. After an exhaustive preprocessing pipeline to remove artifacts, spindles were automatically detected using a complex demodulation-based method. Then, the Wavelet Scalogram was estimated to validate it. Spindle TTV of each participant was also computed for all the conventional EEG frequency bands. Root mean square (RMS) of each TTV signal was calculated as a measure of the total variability of each spindle. Results showed significant differences in the variability between frequencies. Specifically, RMS in the beta-1 frequency band showed higher values as compared to all the other frequency bands (p<0.001). TTV curves showed a dichotomic trend, with lower frequencies showing an increase in the variability before the spindle onset, and higher frequencies showing such increase after the onset. The dependence of the spindle variability with the frequency could be explained by the influence of the multiple cortical generators involved.Clinical Relevance- Sleep spindles are similarly affected in different cognitive-related disorders, which supports the relevance of assessing abnormal sleep patterns as a possible cause for such cognitive deficits.

Rare damaging variants in DNA repair and cell cycle pathways are associated with hippocampal and cognitive dysfunction: a combined genetic imaging study in first-episode treatment-naive patients with schizophrenia

Schizophrenia is a complex neurodevelopmental disorder where changes in both hippocampus and memory-related cognitive functions are central. However, the exact relationship between neurodevelopmental-genetic factors and hippocampal-cognitive dysfunction remains unclear. The general aim of our study is to link the occurrence of rare damaging mutations involved in susceptibility gene pathways to the structure and function of hippocampus in order to define genetically and phenotypically based subgroups in schizophrenia. In the present study, by analyzing the exome sequencing and magnetic resonance imaging data in 94 first-episode treatment-naive schizophrenia patients and 134 normal controls, we identified that a cluster of rare damaging variants (RDVs) enriched in DNA repair and cell cycle pathways was present only in a subgroup including 39 schizophrenic patients. Furthermore, we found that schizophrenic patients with this RDVs show increased resting-state functional connectivity (rsFC) between left hippocampus (especially for left dentate gyrus) and left inferior parietal cortex, as well as decreased rsFC between left hippocampus and cerebellum. Moreover, abnormal rsFC was related to the deficits of spatial working memory (SWM; that is known to recruit the hippocampus) in patients with the RDVs. Taken together, our data demonstrate for the first time, to our knowledge, that damaging rare variants of genes in DNA repair and cell cycle pathways are associated with aberrant hippocampal rsFC, which was further relative to cognitive deficits in first-episode treatment-naive schizophrenia. Therefore, our data provide some evidence for the occurrence of phenotypic alterations in hippocampal and SWM function in a genetically defined subgroup of schizophrenia.

Abnormal functional-structural cingulum connectivity in mania: combined functional magnetic resonance imaging-diffusion tensor imaging investigation in different phases of bipolar disorder

OBJECTIVE

The objective of the study was to investigate the relationship between structural connectivity (SC) and functional connectivity (FC) in the cingulum in bipolar disorder (BD) and its various phases.

METHOD

We combined resting-state functional magnetic resonance imaging and probabilistic tractographic diffusion tensor imaging to investigate FC and SC of the cingulum and its portions, the SC-FC relationship, and their correlations with clinical and neurocognitive measures on sustained attention in manic (n = 21), depressed (n = 20), and euthymic (n = 20) bipolar patients and healthy controls (HC) (n = 42).

RESULTS

First, we found decreased FC between the anterior and posterior parts of the cingulum in manic patients when compared to depressed patients and HC. Second, we observed decreased SC of the cingulum bundle, particularly in its anterior part, in manic patients when compared to HC. Finally, alterations in the cingulum FC (but not SC) correlated with clinical severity scores while changes in the cingulum SC (but not FC) were related with neurocognitive deficits in sustained attention in BD.

CONCLUSION

We demonstrate for the first time a reduction in FC and concomitantly in SC of the cingulum in mania, which correlated with psychopathological and neurocognitive parameters, respectively, in BD. This supports the central role of cingulum connectivity specifically in mania.

Psychopathology of the self and the altered cortical midline structures in psychiatric disorders – a marriage?

The self is central in our mental life and disturbances of the self-figure most prominently in psychopathological symptoms. The cortical midline structures (CMS) have been associated with self-related processing and its changes in schizophrenia, depression and other psychiatric disorders. However, the exact neuronal mechanisms underlying self-related processing in CMS and its changes in psychiatric disorders remain unclear. Especially the neural overlap between high resting state activity levels and self-related processing in CMS is rather puzzling. I present recent data on the rest-self overlap in healthy subjects showing that resting state activity in CMS can predict self-relatedness. The implications for psychological symptoms as in depression and schizophrenia are pointed out.

Disclosure of interest

The author has not supplied his declaration of competing interest.

Resting network is composed of more than one neural pattern: an fMRI study

In resting state, the dynamics of blood oxygen level-dependent signals recorded by functional magnetic resonance imaging (fMRI) showed reliable modular structures. To explore the network property, previous research used to construct an adjacency matrix by Pearson's correlation and prune it using stringent statistical threshold. However, traditional analyses may lose useful information at middle to moderate high correlation level. This resting fMRI study adopted full connection as a criterion to partition the adjacency matrix into composite sub-matrices (neural patterns) and investigated the associated community organization and network features. Modular consistency across subjects was assessed using scaled inclusivity index. Our results disclosed two neural patterns with reliable modular structures. Concordant with the results of traditional intervention, community detection analysis showed that neural pattern 1, the sub-matrix at highest correlation level, was composed of sensory-motor, visual associative, default mode/midline, temporal limbic and basal ganglia structures. The neural pattern 2 was situated at middle to moderate high correlation level and comprised two larger modules, possibly associated with mental processing of outer world (such as visuo-associative, auditory and sensory-motor networks) and inner homeostasis (such as default-mode, midline and limbic systems). Graph theoretical analyses further demonstrated that the network feature of neural pattern 1 was more local and segregate, whereas that of neural pattern 2 was more global and integrative. Our results suggest that future resting fMRI research may take the neural pattern at middle to moderate high correlation range into consideration, which has long been ignored in extant literature. The variation of neural pattern 2 could be relevant to individual characteristics of self-regulatory functions, and the disruption in its topology may underlie the pathology of several neuropsychiatric illnesses.

Grey matter density and GABAA binding potential show a positive linear relationship across cortical regions

Voxel based morphometry (VBM) is a widely used technique for studying the structure of the brain. Direct comparisons between the results obtained using VBM and the underlying histology are limited, however. To circumvent the problems inherent in comparing VBM data in vivo with tissue samples that must generally be obtained post-mortem, we chose to consider GABAA receptors, measured using (18)F-flumazenil PET (18F-FMZ-PET), as non-invasive neural markers to be compared with VBM data. Consistent with previous cortical thickness findings, GABAA receptor binding potential (BPND) was found to correlate positively across regions with grey matter (GM) density. These findings confirm that there is a general positive relationship between MRI-based GM density measures and GABAA receptor BPND on a region-by-region basis (i.e., regions with more GM tend to also have higher BPND).

Glutamate modulates resting state activity in the perigenual anterior cingulate cortex - a combined fMRI-MRS study

The perigenual anterior cingulate cortex (PACC) shows high resting state activity and is considered part of the default-mode network (DMN). However, the biochemical underpinnings of the PACC's high resting state activity remain unclear. While animal-based evidence points toward a role for the glutamatergic system, the modulation of the resting state activity level by itself as distinguished from stimulus-induced activity remains to be shown in humans. Using combined fMRI-MRS in healthy subjects, we here demonstrate that the PACC resting state concentration of glutamate is directly related to the level of resting state activity in the same region. In contrast, no such relationship could be detected during the anticipation of reward and punishment, nor in an independent control region (the left anterior insula). Taken together, our findings demonstrate for the first time the modulation of the PACC resting state activity level by the concentration of glutamate in the same regions. This contributes to a better understanding of the biochemical basis for the brain's resting state activity as well as providing some clues regarding its apparent pathological upregulation in psychiatric disorders like the major depressive disorder.

Neural correlates of a single-session massage treatment

The current study investigated the immediate neurophysiological effects of different types of massage in healthy adults using functional magnetic resonance imaging (fMRI). Much attention has been given to the default mode network, a set of brain regions showing greater activity in the resting state. These regions (i.e. insula, posterior and anterior cingulate, inferior parietal and medial prefrontal cortices) have been postulated to be involved in the neural correlates of consciousness, specifically in arousal and awareness. We posit that massage would modulate these same regions given the benefits and pleasant affective properties of touch. To this end, healthy participants were randomly assigned to one of four conditions: 1. Swedish massage, 2. reflexology, 3. massage with an object or 4. a resting control condition. The right foot was massaged while each participant performed a cognitive association task in the scanner. We found that the Swedish massage treatment activated the subgenual anterior and retrosplenial/posterior cingulate cortices. This increased blood oxygen level dependent (BOLD) signal was maintained only in the former brain region during performance of the cognitive task. Interestingly, the reflexology massage condition selectively affected the retrosplenial/posterior cingulate in the resting state, whereas massage with the object augmented the BOLD response in this region during the cognitive task performance. These findings should have implications for better understanding how alternative treatments might affect resting state neural activity and could ultimately be important for devising new targets in the management of mood disorders.

The narcissistic self and its psychological and neural correlates: an exploratory fMRI study

BACKGROUND

The concept of narcissism has been much researched in psychoanalysis and especially in self psychology. One of the hallmarks of narcissism is altered emotion, including decreased affective resonance (e.g. empathy) with others, the neural underpinnings of which remain unclear. The aim of our exploratory study was to investigate the psychological and neural correlates of empathy in two groups of healthy subjects with high and low narcissistic personality trait. We hypothesized that high narcissistic subjects would show a differential activity pattern in regions such as the anterior insula that are typically associated with empathy.

METHOD

A sample of 34 non-clinical subjects was divided into high (n=11) and low (n=11) narcissistic groups according to the 66th and 33rd percentiles of their scores on the Narcissism Inventory (NI). Combining the psychological, behavioral and neuronal [i.e. functional magnetic resonance imaging (fMRI)] measurements of empathy, we compared the high and low narcissistic groups of subjects.

RESULTS

High narcissistic subjects showed higher scores on the Symptom Checklist-90 - Revised (SCL-90-R) and the 20-item Toronto Alexithymia Scale (TAS-20) when compared to low narcissistic subjects. High narcissistic subjects also showed significantly decreased deactivation during empathy, especially in the right anterior insula.

CONCLUSIONS

Psychological and neuroimaging data indicate respectively higher degrees of alexithymia and lower deactivation during empathy in the insula in high narcissistic subjects. Taken together, our preliminary findings demonstrate, for the first time, psychological and neuronal correlates of narcissism in non-clinical subjects. This might stipulate both novel psychodynamic conceptualization and future psychological-neuronal investigation of narcissism.

Discovering imaging endophenotypes for major depression

Psychiatry research lacks an in-depth understanding of mood disorders phenotypes, leading to limited success of genetics studies of major depressive disorder (MDD). The dramatic progress in safe and affordable magnetic resonance-based imaging methods has the potential to identify subtle abnormalities of neural structures, connectivity and function in mood disordered subjects. This review paper presents strategies to improve the phenotypic definition of MDD by proposing imaging endophenotypes derived from magnetic resonance spectroscopy measures, such as cortical gamma-amino butyric acid (GABA) and glutamate/glutamine concentrations, and from measures of resting-state activity and functional connectivity. The proposed endophenotypes are discussed regarding specificity, mood state-independence, heritability, familiarity, clinical relevance and possible associations with candidate genes. By improving phenotypic definitions, the discovery of new imaging endophenotypes will increase the power of candidate gene and genome-wide associations studies. It will also help to develop and evaluate novel therapeutic treatments and enable clinicians to apply individually tailored therapeutic approaches. Finally, improvements of the phenotypic definition of MDD based on neuroimaging measures will contribute to a new classification system of mood disorders based on etiology and pathophysiology.

The resting brain and our self: self-relatedness modulates resting state neural activity in cortical midline structures

The resting brain shows high neural activity in various regions, the default-mode network, chief among them the cortical midline structures (CMS). The psychological correlate of high resting state neural activity in CMS remains however unclear though speculatively it has been associated with processing of internally-oriented self-relatedness. We used functional MRI to examine internally-oriented self-relatedness during the resting state period. This was indirectly done by letting subjects perceive emotional pictures followed by a fixation cross; the very same pictures were then rated subjectively according to their degree of self-relatedness in a postscanning session. This allowed us to correlate the picture ratings of self-relatedness with signal changes in the subsequent resting state period, i.e. fixation period. The emotional pictures' degree of self-relatedness parametrically modulated subsequent resting state signal changes in various CMS, including ventro- and dorsomedial prefrontal cortex and posterior cingulate cortex. This modulation could be distinguished from effects of emotion dimensions (e.g. valence, intensity) and evoked effects of self-relatedness during the stimulus period itself the latter being observed rather in subcortical regions, e.g. amygdala, ventral striatum, and tectum. In sum, our findings suggest that resting state neural activity in CMS is parametrically and specifically modulated by the preceding stimulus's degree of self-relatedness. This lends further support to the presumed involvement of these regions in processing internally-oriented self-relatedness as distinguished from externally-oriented self-relatedness.

Is our self based on reward? Self-relatedness recruits neural activity in the reward system

Every organism has to evaluate incoming stimuli according to their current and future significance. The immediate value of stimuli is coded by the reward system, but the processing of their long-term relevance implements a valuation system that implicates self-relatedness. The neuronal relationship between reward and self-relatedness remains unclear though. Using event-related functional MRI, we investigated whether self-relatedness induces neural activity in the reward system. Self-relatedness induced signal changes in the same regions that were recruited during reward including the bilateral nucleus accumbens (NACC), ventral tegmental area (VTA) and ventromedial prefrontal cortex (VMPFC). The fMRI signal time courses revealed no differences in early BOLD signals between reward and self-relatedness. In contrast, both conditions differed in late BOLD signals with self-relatedness showing higher signal intensity. In sum, our findings indicate sustained recruitment of the reward system during self-relatedness. These findings may contribute to a better understanding of the reward-based nature of our self.

Neurobiologische Grundlagen depressiver Syndrome

Depressive disorders belong to the most frequent diseases worldwide showing a lifetime prevalence of up to 20%. Moreover they are one of the leading causes for the amount of years lived with disability. Increasing knowledge about the pathological mechanisms underlying depressive syndromes is obtained by using modern neurobiological research-techniques. Thereby some older theories that have been the basis of emotion-research for decades--like the monoamine hypothesis--have been strengthened. In addition new aspects of the pathological processes underlying depressive disturbances have been unraveled. In this review established models and recent findings will be discussed, to bridge various research-fields, ranging from genetics, epigenetics and morphological changes to the functional consequences of depression. Finally therapeutic implications that could be derived from these results will be presented, showing up putative possibilities for diagnosis and treatment of depressive syndromes.

Subjektives Erleben und neuronale Integration im Gehirn: Benötigen wir eine Erste-Person-Neurowissenschaft?

Unlike other medical disciplines psychiatry can be characterized by the special importance of subjective experience. Since subjective experience is tied to First-Person-Perspective and investigation of the brain is possible only in Third-Person-Perspective, the question how subjective experience can be linked to neuronal processes is raised in psychiatry. We suggest a novel methodological approach, First-Person-Neuroscience where subjective experience can be linked directly and systematically to neuronal processes. Due to complexity of the structures and contents of subjective experience, localization in specific brain regions seems inappropriate. Instead, the interplay and coordination of neuronal activity across several brain regions, so-called neuronal integration, should be considered in First-Person-Neuroscience. This is illustrated by two principles of neuronal integration, top-down modulation and reciprocal modulation, whose abnormal function can be related to subjective experience of patients with catatonia and depression. It is concluded that First-Person-Neuroscience can contribute to reveal abnormal brain function in psychiatric disorders and ultimately to development of diagnostic and therapeutic markers.

Was ist „Neuroethik“ — eine Disziplin der Zukunft?

Progress in neuroscience leads not only to novel therapeutic opportunities but also raises several ethical problems. These problems are often subsumed under the term "neuroethics," of which the definition and purpose often remain unclear. We discuss the problems of informed consent, free will, sense of self, and personality in light of recent neuroscientific progress. Due to distinct categories and frames of reference, these philosophical-ethical terms cannot be limited only to the brain; the development of systematic relations is suggested. This accounts for the "special ethical position of the brain." It is concluded that only this sense can neuroethics account for the ethical complexity in neuropsychiatric disorders.

Effects of single-pulse transcranial magnetic stimulation (TMS) on functional brain activity: a combined event-related TMS and evoked potential study

OBJECTIVE

To further evaluate the potential of slew-rate limiting amplifiers to record electrophysiological signals in spite of concurrent transcranial magnetic stimulation (TMS), and to explore the effects of single-pulse TMS on electroencephalographic (EEG) correlates of functional brain activity.

METHODS

Visual-evoked potentials (VEPs) to checkerboards were recorded in 7 right-handed subjects, while single-pulse TMS was applied to the occipital pole either at visual stimulus onset, during the build-up or at the expected peak of the early VEP component P1 (VIS&TMS). Timing of TMS was individually adjusted based on each subject's VEP-latency. A condition of TMS without concurrent visual stimulation (TMS(alone)) served for subtraction purposes (VIS&TMS minus TMS(alone)) to partial out TMS-related contaminations of the EEG signal.

RESULTS

When TMS was applied at visual stimulus onset, VEPs (as calculated by subtraction) perfectly matched control VEPs to visual stimulation alone. TMS at around P1, in contrast, modified the targeted (P1) and the subsequent VEP component (N1), independently of whether TMS was given at build-up or peak.

CONCLUSIONS

The retrieval of regular VEPs with concomitant TMS at visual stimulus onset suggests that the employed EEG system and subtraction procedure are suited for combined EEG-TMS studies. The VEP changes following TMS at around P1 provide direct clues on the temporal dynamics of TMS pulse effects on functional activity in the human brain. Our data suggest effects of relatively long duration (approximately 100 ms) when TMS is applied while functional neuronal activity evolves.

Differential effects of low-frequency rTMS at the occipital pole on visual-induced alpha desynchronization and visual-evoked potentials

Visual-induced alpha desynchronization (VID) and visual-evoked potentials (VEPs) characterize occipital activation in response to visual stimulation but their exact relationship is unclear. Here, we tested the hypothesis that VID and VEPs reflect different aspects of cortical activation. For this purpose, we determined whether VID and VEPs are differentially modulated by low-frequency repetitive transcranial magnetic stimulation (rTMS) over the occipital pole. Scalp EEG responses to visual stimuli (flashed either to the left or to the right visual field) were recorded for 8 min in six healthy subjects (1) before, (2) immediately following, and (3) 20 min after left occipital rTMS (1 Hz, 10 min). The parameters aimed to reduce cortical excitability beyond the end of the TMS train. In addition, simple reaction times to visual stimulation were recorded (left or right hand in separate blocks). In all subjects, VID was significantly and prominently reduced by rTMS (P = 0.0001). In contrast, rTMS failed to modulate early VEP components (P1/N1). A moderate effect was found on a late VEP component close to manual response onset (P = 0.014) but this effect was in the opposite direction to the VID change. All changes were restricted to the targeted left occipital cortex. The effects were present only after right visual field stimulation when a right hand response was required, were associated with a behavioral effect, and had washed out 20 min after rTMS. We conclude that VID and early VEPs represent different aspects of cortical activation. The findings that rTMS did not change early VEPs and selectively affected VID and late VEPs in conditions where the visual input must be transferred intrahemispherically for visuomotor integration (right visual field/right hand) are suggestive of rTMS interference with higher-order visual functions beyond visual input. This is consistent with the idea that alpha desynchronization serves an integrative role through a corticocortical "gating function."

Catatonia and neuroleptic malignant syndrome: psychopathology and pathophysiology

Catatonia was originally described as a psychomotor syndrome in the 19th century by Kahlbaum including motor, affective and behavioral symptoms. Later, at the beginning of the 20th century, catatonia was rather considered as the motoric manifestation of schizophrenia. Accordingly, neuropathological research focused predominantly on those neuroanatomical substrates, i.e. the basal ganglia being primarily involved in the generation of movements. Even though some authors observed minor alterations in the basal ganglia, consistent findings in these subcortical structures could not be obtained. Since neuroleptics can induce catatonic-like symptoms i.e. neuroleptic malignant syndrome (NMS), there has been a recent re-emergence in clinical and scientific interest in catatonia. However, exact psychopathological and pathophysiological characterization of both NMS and catatonia remains unclear.Clinically, catatonia and NMS show more or less similar motor symptoms i.e. akinesia. These may be accounted for by dysregulation in cortical-subcortical circuits between motor/premotor cortex and basal ganglia i.e. the so-called "motor loop". While in NMS the "motor loop" may be dysregulated by neuroleptic blockade of subcortical striatal D-2 receptors one may rather assume cortical gaba-ergic alteration in catatonia. The premotor/motor cortex and consecutively the "motor loop" may be dysregulated by gaba-ergic abnormalities in orbitofrontal cortex. Gaba-ergic cortical dysfunction may account for affective and behavioural abnormalities in catatonia which cannot be observed as such in NMS. Consequently, one may characterize catatonia as a cortical "psychomotor syndrome" while NMS may rather be regarded as subcortical "motor syndrome".

Serum levels of amitriptyline and therapeutic effect in non-delusional moderately to severely depressed in-patients: a therapeutic window relationship

In a prospective, open clinical study, the relationship between serum levels of amitriptyline (At) and nortriptyline (Nt) and the therapeutic effect after 6 weeks of treatment was investigated. Serum levels were measured by gas-liquid chromatography and the therapeutic effect was assessed by the Hamilton Depression Rating Scale (HAMD) and the Clinical Global Impression Scale (CGI). A number of 25 non-delusional, moderate to severely depressed inpatients were included. A therapeutic window relationship was detected by means of regression analysis (quadratic model). Low and high serum levels were associated with low therapeutic effect. In an intermediate range, the probability of good therapeutic effect was increased. This relationship reached significance for the serum levels of At (p < 0.05) and a trend for the sum of serum levels of At and Nt (p < 0.1). As expressed by the regression coefficient r2, about 25% to 35% of the variability of therapeutic effect was explained by serum levels. Dichotomized data sets according to limits of final values of HAMD and CGI as well as limits of a therapeutic window of 70 ng/ml and 200 ng/ml (sum of At and Nt) revealed significant differences by means of Fisher's exact test (p < 0.05). Furthermore, increased ratios of serum level of Nt per serum level of At were found to be associated with decreased therapeutic effect. Thus, the present data support the existence of a therapeutic window of serum levels of At in depression. Also taking into account other reports, this therapeutic window can be defined as being between about 70 and 220 ng/ml. The assay of serum levels of At can be used to lower the risk of unsatisfactory therapeutic outcome.

[Reconstruction of mutism. Studies of subjective experiences of former patients with the modified Landfield categories]

OBJECTIVE

The subjective experience of catatonic patients was investigated with the repertory grid-technique after recovery from the acute state of disease and compared with non-catatonic schizoaffective and depressive patients.

METHODS

The sample consists of 18 catatonic patients, 22 schizoaffective, 16 unipolar depressive, 8 unipolar manic and 23 patients with bipolar affective disorder as well as of 32 psychiatrically healthy orthopaedic controls. Interviews were held well before discharge. The contents of personal constructs was analyzed by means of modified Landfield categories.

RESULTS

"Self" of catatonic patients did not differ significantly from the other groups. The "Idealself" of catatonic patients differed significantly in the categories "high self esteem" (from the controls and the non-catatonic group) and "high empathy" (from the controls). The "disease-self" ("In the acute catatonic state") was construed as isolated (lack of social contact). The results underline the importance of an active therapeutical interaction in the acute catatonic state. The modified Landfield Categories proved to be a useful psychodiagnostic instrument for the idiographic assessment of personality in particular, and for psychiatric therapy research in general.

Personality and object relations in patients with affective disorders: idiographic research by means of the repertory grid technique

BACKGROUND

This paper presents an idiographic approach to evaluate the self concept and the self-object-relationship of patients suffering from affective disorders.

METHODS

Significant dimensions of the personality and the object relations of 127 depressive patients and 34 orthopaedic patients were investigated with the repertory grid-technique. The self concept and the object relations were compared by means of nomothetically used idiographic results after recovery from manifest depression.

RESULTS

'Low self esteem' was frequently found in patients with a long lasting course of illness and the ICD-10-diagnoses of 'bipolar affective disorder' and 'dysthymia'. The object relations of the depressive sample were characterised by the dimension 'symbiotic near'; 'ambivalent' and 'indifferent' partnership relationships were found much more frequently in the controls.

CONCLUSIONS

The idiographic results help to differentiate the spectrum of affective disorders. They underline the importance of the interpersonal dimension of depression and may be used as a basis of a therapeutic appraisal.

LIMITATIONS

The repertory grid-technique may not be used as a diagnostic instrument. However, the combination of idiographic results with further clinical informations enables the multidimensional assessment of the self concept and psychosocial coping mechanisms.

Delayed onset of late movement-related cortical potentials and abnormal response to lorazepam in catatonia

Catatonia is a psychomotor syndrome with an inability to execute and terminate movements completely, leading consecutively to akinesia and posturing, which both respond almost immediately to benzodiazepines, i.e. gaba-potentiators like lorazepam. However, pathophysiological mechanisms of cortical motor and gaba-ergic dysfunction remain unclear. We therefore investigated movement-related cortical potentials (MRPs) and movement kinematics during a motor task before and after lorazepam. Ten akinetic catatonic patients were compared with 10 psychiatric (similar age, sex, medication, and underlying psychiatric disease but without catatonic syndrome) and 20 healthy controls. MRPs from frontal (F), central (C), and parietal (P) sites were recorded to obtain measures of early and late readiness potential and movement potential. Kinematic measures included parameters for amplitude of movements, peak velocity, average duration of movements, elevation angle, and angle velocity. The motor task consisted in self-initiated extension of the right index finger. All catatonic and psychiatric control patients received intravenous lorazepam (1mg), whereas healthy controls were subjected to a placebo-controlled (10 received lorazepam, 10 received placebo) double-blind study design.Catatonics showed a significantly delayed onset of late readiness and movement potential in central electrodes (Cz, C3) compared with psychiatric and healthy controls. This delayed onset correlated significantly with catatonic motor symptoms and movement duration. Lorazepam led to significantly stronger delays in onset of late readiness potential in left fronto-parietal (F3, C3, P3) electrodes in catatonic patients than in psychiatric and healthy controls. It is concluded that delayed latencies in late MRP components in catatonic patients may reflect their inability to execute and terminate movements completely. Differential and stronger response to lorazepam in catatonia suggests dysfunction in inhibitory control of cortical motor function with increased gaba-ergic sensitivity.

[Self concept and object relations of patients with affective disorders--individual centered diagnosis with the repertory-grid technique]

Significant dimensions of the self concept and the object relations of 127 depressive patients and 34 orthopaedic patients were investigated with the repertory-grid-technique. Self concept and object relations were compared by means of nomothethically used idiographic results after recovery from manifest depression. The object relations of the depressive sample were characterised by the dimension "symbiotic near"; "ambivalent" and "indifferent" partnership relationships were found much more frequently in the controls. The idiographic results contribute to a differentiation of the spectrum of affective disorders. They underline the importance of the interpersonal dimension of depression and may be used as a basis of a therapeutic orientation.

Right lower prefronto-parietal cortical dysfunction in akinetic catatonia: a combined study of neuropsychology and regional cerebral blood flow

BACKGROUND

Catatonia is a psychomotor syndrome that can be characterized by behavioural, affective and motor abnormalities. In order to reveal further underlying pathophysiological mechanisms of psychomotor disturbances in catatonia we investigated neuropsychological function and regional cerebral perfusion (r-CBF) in a combined study.

METHODS

Ten catatonic patients were investigated with Tc-99mECD brain SPECT and compared with 10 psychiatric (similar age, sex, medication and underlying psychiatric diagnosis but without catatonic syndrome) and 20 healthy controls. Neuropsychological measures included tests for general intelligence, attention, executive functions and right parietal visual-spatial abilities. Correlational analyses were performed between neuropsychological measures, catatonic symptoms and r-CBF.

RESULTS

Catatonic patients showed a significant decrease of r-CBF in right lower and middle prefrontal and parietal cortex compared with psychiatric and healthy controls as well as significantly poorer performance in visual-spatial abilities associated with right parietal function. Correlational analysis revealed significant correlations between visual-spatial abilities and right parietal r-CBF only in psychiatric and healthy controls but not in catatonic patients. In contrast, attentional measures correlated significantly with motor symptoms, visual-spatial abilities and right parietal r-CBF in catatonia only but not in psychiatric or in healthy controls.

CONCLUSION

Findings are preliminary but suggest right lower prefronto-parietal cortical dysfunction in catatonia, which may be closely related to psychomotor disturbances.

Functional dissociation between medial and lateral prefrontal cortical spatiotemporal activation in negative and positive emotions: a combined fMRI/MEG study

The orbitofrontal cortex has been cytoarchitectonically and connectionally subdivided into a medial and a lateral part which are assumed to subserve distinct functions in emotional processing. However the exact spatiotemporal mechanisms of negative and positive emotional processing in medial and lateral orbitofrontal cortex remain unclear. We therefore investigated spatiotemporal orbitofrontal and prefrontal cortical activation patterns during emotional stimulation in a combined fMRI/MEG study. We investigated 10 healthy subjects, 5 women and 5 men. Positive and negative pictures from the International Affective Picture system (IAPS) were used for emotional stimulation, whereas neutral and gray pictures were taken as control conditions. fMRI/MEG measurements covered the whole frontal lobe and a time window between -2000 and +200 ms around motor responses (right index finger extension) associated with each picture. Positively and negatively correlated activities were determined in various prefrontal/frontal cortical regions in fMRI. Isocontour maps and single dipoles in MEG were analyzed in 50 ms time windows ranging from -2000 to +200 ms. Dipoles and fMR images were mapped on three-dimensional anatomical MRI so that anatomical localization of single dipoles and regional fMRI activity could be compared. Both negative and positive emotional conditions differed from non-emotional control conditions by strong orbitofrontal and lateral prefrontal activation as well as by the presence of early magnetic fields (-1700 to +1100 ms). Negative emotional processing was characterized by strong medial orbitofrontal activation and earlier (-1700 ms), stronger and more medially oriented orbitofrontal dipoles. In contrast positive emotional processing showed a rather strong activation in lateral prefrontal cortex with later (-1500 ms), weaker and more laterally oriented orbito and prefrontal dipoles. Negative emotional processing can be characterized by strong and early medial orbitofrontal cortical activation, whereas positive emotional processing showed rather later and weaker activation in lateral orbitofrontal/prefrontal cortex. Such a functional dissociation between medial and lateral orbito-frontal/prefrontal cortex during negative and positive emotional processing lends further support to the assumption of a functional subdivision in the orbitofrontal cortex.

[Effect of activation tasks on acute neuroleptic-induced akathisia]

In this study, we investigated experimentally the effects of different activation procedures on both motor and psychic symptoms in of 11 in-patients with acute neuroleptic-induced akathisia using the Hillside and Barnes akathisia rating scales and videotape rating technique. Motor activation was achieved by finger tapping. Cognitive activation tasks consisted of sequences of mental calculations which were designed either to be easy to perform or to produce stress due to a given time limit or to more difficult calculation operations, respectively. Motor as well as psychic symptoms of akathisia decreased during both motor and simple cognitive activation without stress. By contrast, stress-producing calculation tasks led to an increase in motor and psychic symptoms immediately following the task performance. These possibly specific effects of activation procedures on symptoms might be useful in differentiating acute neuroleptic-induced akathisia from other neuroleptic-induced and extrapyramidal movement disorders.

Decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia: investigation of in vivo benzodiazepine receptor binding

OBJECTIVES

Catatonia is a psychomotor syndrome with concomittant akinesia and anxiety which both respond almost immediately to benzodiazepines such as lorazepam. The benzodiazepine receptor distribution was therefore investigated in akinetic catatonia with single photon emission tomography (SPECT) using iodine-123-iomazenil ((123) I Iomazenil).

METHODS

Ten akinetic catatonic patients, 10 psychiatric controls (similar age, sex, medication, and underlying psychiatric diagnosis but without catatonic syndrome), and 20 healthy controls were investigated with SPECT 2 hours after injection of (123) I Iomazenil. To exclude potential effects of cerebral perfusion (r-CBF) r-CBF was additionally investigated with Tc-99mECD SPECT.

RESULTS

Catatonic patients showed significantly lower iomazenil binding and altered right-left relations in the left sensorimotor cortex compared with psychiatric (p<0.001) and healthy (p<0.001) controls. In addition, there was significantly lower r-CBF in the right lower prefrontal and parietal cortex in catatonia whereas in the left sensorimotor cortex no differences in r-CBF between groups were found. Catatonic motor and affective symptoms showed significant correlations (p<0.05) with benzodiazepine binding in the left sensorimotor cortex as well as with right parietal r-CBF.

CONCLUSIONS

Reduced iomazenil binding suggests decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia. In addition to reduced GABA-A receptor density in the left sensorimotor cortex the parietal cortex seems to be involved in pathophysiology of catatonic symptoms. It is concluded that, considering results from correlation analyses, both emotional and motor symptoms in catatonia seem to be closely related to left sensorimotor and right parietal alterations.

Cortical sulcal enlargement in catatonic schizophrenia: a planimetric CT study

To determine whether patients with catatonic schizophrenia have specific alterations in brain morphology, internal (ventricles) and external (frontal, temporal, parieto-occipital) components of the cerebrospinal fluid (CSF) spaces were examined morphometrically. Planimetric measurements of computed tomographic (CT) scans from 37 patients with catatonic schizophrenia, 28 patients with hebephrenic schizophrenia, and 39 patients with paranoid schizophrenia, all diagnosed according to DSM-III-R criteria, were compared with separate age- and sex-matched non-psychiatric control groups, respectively. The areas of the frontal sulci, the parieto-occipital sulci, the inter-hemispheric fissure, and the lateral and third ventricles were measured separately for the right and left hemispheres. Catatonic patients showed significant enlargements in almost all CSF spaces, especially in the left fronto-temporal area which, in addition, correlated significantly with illness duration. Hebephrenic patients showed selective enlargements in left temporal and left/right lower frontal cortical sulci, whereas paranoid schizophrenic patients showed no enlargements but significant correlations between left temporal cortical sulcal volume and illness duration. Alterations in temporal cortical areas were present in all three sub-types of schizophrenia. In addition to temporal alterations, hebephrenic schizophrenia was characterised by lower frontal (i.e. orbitofrontal) enlargement. Catatonic schizophrenia, the most severe sub-type with regard to clinical symptomatology and brain pathology, showed fronto-parietal cortical alterations.

Reduced activation and altered laterality in two neuroleptic-naive catatonic patients during a motor task in functional MRI

BACKGROUND

Catatonia, a symptom complex with motor, affective and cognitive symptoms seen in a variety of psychotic conditions and with organic disease, was examined using a motor task using functional magnetic resonance imaging (fMRI).

METHODS

Two acute catatonic patients and two age- and sex-matched healthy controls performed sequential finger opposition (SFO) after being medicated with 2 mg of lorazepam (i.v.). Functional magnetic resonance images were collected using a gradient echo pulse sequence (EPI).

RESULTS

Patients with catatonia showed reduced motor activation of the contralateral motor cortex during SFO of the right hand, ipsilateral activation was similar for patients and controls. There were no differences in the activation of the SMA. During left hand activation the right-handed catatonic patients showed more activation in the ipsilateral cortex, a reversal from the normal pattern of activation in which the contralateral side shows four to five times more activation than the ipsilateral side.

CONCLUSIONS

In catatonic patients there is a decreased activation in motor cortex during a motor task compared to matched medicated healthy controls. In addition activation of the non-dominant side, left-handed activity in right-handed patients, results in a total reversal of the normal pattern of lateral activation suggesting a disturbance in hemispheric localization of activity during a catatonic state.

Impairment in visual-spatial function in catatonia: a neuropsychological investigation

Catatonia is a psychomotor syndrome with motor and behavioral abnormalities which may be due to alterations in fronto-parietal cortical function. We therefore investigated neuropsychological tasks (attention, executive, visual-spatial, working memory) associated with frontal and parietal cortical function. Thirteen catatonic patients, diagnosed as catatonic according to criteria by Rosebush and Bush, were compared with 13 psychiatric non-catatonic controls (matched with regard to underlying psychiatric diagnosis, age, sex, and medication), and 13 age- and sex-matched healthy controls. Catatonics showed significantly poorer performances and different neuropsychological intercorrelation patterns in visual spatial object perception (VOSPobject) than psychiatric and healthy controls. In addition, we found significant correlations between catatonic symptoms, visual-spatial abilities, and attentional measures (i.e., d2, CWI). Catatonia was characterized by specific visual-spatial deficits which are related to attentional abilities and right parietal cortical function. The data suggest attentional-motor and fronto-parietal dysfunction in catatonia, a conclusion which should be considered as preliminary, however, due to the small sample size.

Catatonia as a psychomotor syndrome: a rating scale and extrapyramidal motor symptoms

BACKGROUND

Catatonia was first described by Kahlbaum as a psychomotor disease with motor, behavioral, and affective symptoms. In keeping with this concept, we developed a rating scale for catatonia (Northoff Catatonia Scale [NCS]) with three different categories of symptoms (i.e., motor, behavioral, affective). Furthermore, the question of the relationship among catatonic symptoms, extrapyramidal motor symptoms, and neuroleptics was addressed in the present study.

METHOD

34 acute catatonic patients and 68 age-, sex-, diagnosis-, and medication-matched psychiatric control subjects were investigated on days 0, 1, 3, 7, and 21 with the NCS, with other already validated catatonia rating scales by Rosebush, Bush (BFCRS), and Rogers (MRS), as well as with scales for hypokinetic (SEPS) and dyskinetic (AIMS) extrapyramidal motor features. Validity and reliability of the new scale, factor analysis, correlational analysis, and differences between catatonic patients and psychiatric control subjects were statistically calculated.

RESULTS

NCS showed high validity (i.e., significant positive correlations [p <0.0001] with the other scales, significant differences between catatonic and control subjects), high intra-and interrater reliabilities (r = 0.80-0.96), and high affective subscores. Factor analysis revealed four factors best characterized as affective, hypoactive, hyperactive, and behavioral. Catatonic scores in NCS correlated significantly with AIMS on day 0 and SEPS on days 7 and 21. There were no significant differences in catatonic (i.e., NCS, MRS, BFCRS) and extrapyramidal (i.e., AIMS, SEPS) scores between neuroleptically treated and untreated catatonic subjects.

CONCLUSIONS

The following conclusions were drawn: (1) the NCS has to be considered as a valid and reliable rating instrument for catatonia; (2) catatonia can be characterized by psychomotor symptoms encompassing motor, affective, and behavioral alterations; and (3) extrapyramidal hyperkinesias like dyskinesias are apparently closely related to catatonic symptoms which, in general, seem to be relatively independent of previous neuroleptic medication.

[Subjective experiences of patients with acute neuroleptic-induced akathisia]

Neuroleptic-induced akathisia is a clinically important neuropsychiatric syndrome with mainly subjectively experienced psychic symptoms on the one hand and well-observable motor signs on the other. There is no general consensus of opinion on the relative importance of these two aspects for diagnosing akathisia. Hence, differential diagnosis is difficult and in the absence of a biological marker it depends crucially on clinical judgement. Systematic investigation of 27 in-patients via a semistructural interview, a self-assessment scale (20 in-patients) and established akathisia rating scales (Hillside, Barnes, Prince Henry Hospital and Chouinard) revealed four characteristics of subjective experience in acute neuroleptic-induced akathisia: 1. perception of a foreign but nevertheless inner compulsion to move; 2. lack of control over motor behaviour; 3. feeling of inhibition of purposeful actions and 4. subjectively close or inseparable relationship between inner restlessness and restless movements. These features are strongly interrelated and correlate with severity of akathisia. They could be useful in differentiating akathisia from other states of restlessness. The results of this study are discussed in context of the literature on clinical phenomenology of akathisia. We propose a symptom-severity model of akathisia emphasizing psychodynamic aspects with considerable consequences for diagnosis and quantification of the disorder. The model points to the relevance of patient exploration for optimizing diagnostic reliability and should be taken into account when developing new and valid akathisia rating instruments.

Schizophrenia and anteroventral thalamic nucleus: selective decrease of parvalbumin-immunoreactive thalamocortical projection neurons

This study was designed to examine possible anatomical changes of thalamocortical circuits in schizophrenics. Previous immunocytochemical studies have shown that parvalbumin, a calcium-binding protein, occurs in thalamocortical projection neurons, but not in GABAergic interneurons in the anteroventral thalamic nucleus (AN). Using parvalbumin-immunocytochemistry we investigated the densities of thalamocortical projection neurons in the AN of schizophrenic cases (n = 12) and controls (n = 14). The densities of all neurons in the AN were estimated by Nissl-staining. The majority of thalamocortical projection neurons in AN were identified by parvalbumin-immunoreaction. Significantly reduced densities of thalamocortical projection neurons were estimated in the right (P = 0.003) and left AN (P = 0.018) in schizophrenic subjects. The densities of all neurons in right and left AN were also diminished in schizophrenics; however, these decreases did not reach statistical significance. The reductions of parvalbumin-positive thalamocortical projection neurons were not correlated with the length of disease, this finding supporting the neurodevelopmental etiology of structural abnormalities in schizophrenia.

[The symptomology of akathisia]

The phenomenon of akathisia is characterised by a subjective feeling of inner agitation accompanied by general motoric restlessness, which particularly affects the legs. It is mainly the inner agitation from which the patients suffer, but which they often cannot describe in any detail. The psychopathology of akathisia is presented in a case report, the emphasis being on a detailed description of inner agitation. Furthermore, motor, affective and cognitive symptoms of akathisia are pointed out. Finally, differential diagnosis of akathisia and standardised scales for assessment are discussed.

Glutamatergic dysfunction in catatonia? Successful treatment of three acute akinetic catatonic patients with the NMDA antagonist amantadine

Therapeutic efficiacy of the NMDA antagonist amantadine is reported in three acute neuroleptic free akinetic catatonic patients. Intravenous infusion of amantadine led to the resolution of catatonic symptoms and considerable reductions of scores in various motor scales (Simpson Angus scale for extrapyramidal side effects (SEPS), the abnormal involuntary movement scale (AIMS), Rogers catatonia and schizophrenia scales). The therapeutic effect of amantadine showed a characteristic temporal pattern with most pronounced effects four to six hours after administration and recurrence of catatonic symptoms by 24 hours later, at least partially. Such a temporal pattern of therapeutic efficacy and decreasing efficacy occurred in all three patients on all days. The results suggest the central importance of glutamatergic dysfunction in catatonic syndrome.

Do brain tissue transplants alter personal identity? Inadequacies of some "standard" arguments

Currently, brain tissue transplantations are being developed as a clinical-therapeutic tool in neurodegenerative diseases such as Parkinson's or Alzheimer's disease. From an ethical point of view, distinguishing between the preservation and an alteration of personal identity seems to be central to determining the scope for further application of brain tissue transplantation therapy. The purpose of this article is to review "standard" arguments which are used on the one hand by proponents to prove preservation of personal identity and by opponents on the other hand to prove that brain tissue transplantation results in an altered personal identity. Proponents and opponents are shown to use the same arguments, albeit with different presuppositions. These presuppositions concern the meaning of the term "identity", either numerical or qualitative, the definition of brain identity, either structurally or functionally, and the relationship between mental states, psychological functions and neurophysiological properties as criteria for personal identity. Furthermore the respective neurophysiological, clinical and philosophical evidence for the different presuppositions are discussed. It is concluded that evaluation of personal identity in brain tissue transplantation should not only rely on the "standard" arguments but, additionally, neurophysiological, clinical and philosophical implications should be discussed.