Spatiotemporal Psychopathology - An integrated brain-mind approach and catatonia

Arthur Schopenhauer: An underappreciated philosopher in psychiatry and his applied epistemology of body and self- experience

BACKGROUND

Arthur Schopenhauer (1788-1860) was one of the most important thinkers of the 19th century. Although his writings have exerted great influence in many different disciplines, his epistemological concepts and analysis of the body and self-experience were rarely considered in the context of psychiatric research of schizophrenia spectrum disorders (SSD) and depression (MDD).

METHODS

The method applied for the study of anomalous self and body-experience first consists in the close reading and analysis of Schopenhauer's most influential writings, namely his opus magnus "The World as Will and Representation" and his dissertation "On the Fourfold Root of the Principle of Sufficient Reason". Second, psychopathological and phenomenological aspects of the anomalous body and self, as well as altered space and time experience, are discussed by means of Schopenhauer's philosophy and four patient cases.

RESULTS

Schopenhauer's insights contribute to contemporary psychiatry by (1) unifying materialistic (neurobiological) and idealistic (subjective) conceptions of psychiatric disorders and improving the awareness of methods in psychiatric research; (2) emphasizing the integral significance of the body as a gateway to the surrounding world and basal self-experience; (3) delineating subjective space and time-experience as crucial dimensions of the conditio humana in SSD and MDD; and (4) demonstrating the feasibility of transferring his theories directly to clinical case vignettes stemming from the daily clinical routine.

CONCLUSION

Close reading of Schopenhauer's texts might help bridge the gap between different scientific methods in psychiatry and overcome the translational crisis of contemporary psychiatry by unifying neurobiological and subjective approaches to SSD and MDD.

Temporal imprecision of phase coherence in schizophrenia and psychosis-dynamic mechanisms and diagnostic marker

Schizophrenia (SCZ) is a complex disorder in which various pathophysiological models have been postulated. Brain imaging studies using EEG/MEG and fMRI show altered amplitude and, more recently, decrease in phase coherence in response to external stimuli. What are the dynamic mechanisms of such phase incoherence, and can it serve as a differential-diagnostic marker? Addressing this gap in our knowledge, we uniquely combine a review of previous findings, novel empirical data, and computational-dynamic simulation. The main findings are: (i) the review shows decreased phase coherence in SCZ across a variety of different tasks and frequencies, e.g., task- and frequency-unspecific, which is further supported by our own novel data; (ii) our own data demonstrate diagnostic specificity of decreased phase coherence for SCZ as distinguished from major depressive disorder; (iii) simulation data exhibit increased phase offset in SCZ leading to a precision index, in the millisecond range, of the phase coherence relative to the timing of the external stimulus. Together, we demonstrate the key role of temporal imprecision in phase coherence of SCZ, including its mechanisms (phase offsets, precision index) on the basis of which we propose a phase-based temporal imprecision model of psychosis (PTP). The PTP targets a deeper dynamic layer of a basic disturbance. This converges well with other models of psychosis like the basic self-disturbance and time-space experience changes, as discussed in phenomenological and spatiotemporal psychopathology, as well as with the models of aberrant predictive coding and disconnection as in computational psychiatry. Finally, our results show that temporal imprecision as manifest in decreased phase coherence is a promising candidate biomarker for clinical differential diagnosis of SCZ, and more broadly, psychosis.

A systematic scoping review of rodent models of catatonia: Clinical correlations, translation and future approaches

Catatonia is a psychiatric disorder, which subsumes a plethora of affective, motor and behavioral symptoms. In the last two decades, the number of behavioral and neuroimaging studies on catatonia has steadily increased. The majority of behavioral and neuroimaging studies in psychiatric patients suggested aberrant higher-order frontoparietal networks which, on the biochemical level, are insufficiently modulated by gamma-aminobutyric acid (GABA)-ergic and glutamatergic transmission. However, the pathomechanisms of catatonic symptoms have rarely been studied using rodent models. Here, we performed a scoping review of literature available on PubMed for studies on rodent models of catatonia. We sought to identify what we could learn from pre-clinical animal models of catatonia-like symptoms, their underlying neuronal correlates, and the complex molecular (i.e. genes and neurotransmitter) mechanisms by which its modulation exerts its effects. What becomes evident is that although many transgenic models present catatonia-like symptoms, they have not been used to better understand the pathophysiological mechanisms underlying catatonia so far. However, the identified neuronal correlates of catatonia-like symptoms correlate to a great extent with findings from neuroscience research in psychiatric patients. This points us towards fundamental cortical-striatal-thalamocortical and associated networks modulated by white matter inflammation as well as aberrant dopaminergic, GABAergic, and glutamatergic neurotransmission that is involved in catatonia. Therefore, this scoping review opens up the possibility of finally using transgenic models to help with identifying novel target mechanisms for the development of new drugs for the treatment of catatonia.

Microstructural white matter biomarkers of symptom severity and therapy outcome in catatonia: Rationale, study design and preliminary clinical data of the whiteCAT study

The number of magnetic resonance imaging (MRI) studies on neuronal correlates of catatonia has dramatically increased in the last 10 years, but conclusive findings on white matter (WM) tracts alterations underlying catatonic symptoms are still lacking. Therefore, we conduct an interdisciplinary longitudinal MRI study (whiteCAT) with two main objectives: First, we aim to enroll 100 psychiatric patients with and 50 psychiatric patients without catatonia according to ICD-11 who will undergo a deep phenotyping approach with an extensive battery of demographic, psychopathological, psychometric, neuropsychological, instrumental and diffusion MRI assessments at baseline and 12 weeks follow-up. So far, 28 catatonia patients and 40 patients with schizophrenia or other primary psychotic disorders or mood disorders without catatonia have been studied cross-sectionally. 49 out of 68 patients have completed longitudinal assessment, so far. Second, we seek to develop and implement a new method for semi-automatic fiber tract delineation using active learning. By training supportive machine learning algorithms on the fly that are custom tailored to the respective analysis pipeline used to obtain the tractogram as well as the WM tract of interest, we plan to streamline and speed up this tedious and error-prone task while at the same time increasing reproducibility and robustness of the extraction process. The goal is to develop robust neuroimaging biomarkers of symptom severity and therapy outcome based on WM tracts underlying catatonia. If our MRI study is successful, it will be the largest longitudinal study to date that has investigated WM tracts in catatonia patients.

Extension, translation and preliminary validation of the Northoff Scale for Subjective Experience in Catatonia (NSSC)

BACKGROUND

In the last two decades, much neuroscientific research has been done on the pathomechanisms of catatonia. However, catatonic symptoms have mainly been assessed with clinical rating scales based on observer ratings. Although catatonia is often associated with strong affective reactions, the subjective domain of catatonia has simply been neglected in scientific research.

METHODS

The main objective of this study was to modify, extend and translate the original German version of the Northoff Scale for Subjective Experience in Catatonia (NSSC) and to examine its preliminary validity and reliability. Data were collected from 28 patients diagnosed with catatonia associated with another mental disorder (6A40) according to ICD-11. Descriptive statistics, correlation coefficients, internal consistency and principal component analysis were employed to address preliminary validity and reliability of the NSSC.

RESULTS

NSSC showed high internal consistency (Cronbach's alpha = 0.92). NSSC total scores were significantly associated with Northoff Catatonia Rating Scale (r = 0.50, p < .01) and Bush Francis Catatonia Rating Scale (r = 0.41, p < .05) thus supporting its concurrent validity. There was no significant association between NSSC total score and Positive and Negative Symptoms Scale total (r = 0.26, p = .09), Brief Psychiatric Rating Scale (r = 0.29, p = .07) and GAF (r = 0.03, p = .43) scores.

CONCLUSION

The extended version of the NSSC consists of 26 items and was developed to assess the subjective experience of catatonia patients. Preliminary validation of the NSSC revealed good psychometric properties. NSSC is a useful tool for everyday clinical work to assess the subjective experience of catatonia patients.

Overcoming the translational crisis of contemporary psychiatry - converging phenomenological and spatiotemporal psychopathology

Despite all neurobiological/neurocomputational progress in psychiatric research, recent authors speak about a 'crisis of contemporary psychiatry'. Some argue that we do not yet know the computational mechanisms underlying the psychopathological symptoms ('crisis of mechanism') while others diagnose a neglect of subjectivity, namely first-person experience ('crisis of subjectivity'). In this perspective, we propose that Phenomenological Psychopathology, due to its focus on first-person experience of space and time, is in an ideal position to address the crisis of subjectivity and, if extended to the brain's spatiotemporal topographic-dynamic structure as key focus of Spatiotemporal Psychopathology, the crisis of mechanism. We demonstrate how the first-person experiences of space and time differ between schizophrenia, mood disorders and anxiety disorders allowing for their differential-diagnosis - this addresses the crisis of subjectivity. Presupposing space and time as shared features of brain, experience, and symptoms as their "common currency", the structure of abnormal space and time experience may also serve as template for the structure of the brain's spatiotemporal neuro-computational mechanisms - this may address the crisis of mechanism. Preliminary scientific evidence in our examples of schizophrenia, bipolar disorder, anxiety disorder, and depression support such clinically relevant spatiotemporal determination of both first-person experience (crisis of subjectivity) and the brain's neuro-computational structure (crisis of mechanism). In conclusion, converging Phenomenological Psychopathology with Spatiotemporal Psychopathology might help to overcome the translational crisis in psychiatry by delineating more fine-grained neuro computational and -phenomenal mechanisms; this offers novel candidate biomarkers for diagnosis and therapy including both pharmacological and non-pharmacological treatment.

[Spatiotemporal psychopathology-German version of the Scale for Space and Time Experience in Psychosis (STEP) : A validated measurement instrument for the assessment of spatial and temporal experience in psychotic disorders]

Historical authors (e.g., Ludwig Binswanger and Eugène Minkowski) postulated that the experience of patients with schizophrenia is characterized by time fragmentation. From a clinical perspective, patients with schizophrenia also suffer from difficulties in spatial perception (e.g., abnormalities in the experience of interpersonal distance and spatial orientation). Although these changes can lead to a serious detachment from reality, to considerable suffering of the affected persons and to difficulties in the therapeutic process, the abnormal experience of space and time in psychotic disorders has not yet been sufficiently investigated. One possible reason is the lack of appropriate and standardized instruments that quantify the experience of space and time in patients with psychotic disorders. Based on an innovative concept, the so-called spatiotemporal psychopathology (STPP), a clinical rating scale for the systematic-quantitative assessment of spatial and temporal experience in patients with psychotic disorders was developed. This article presents the German version of the Scale for Space and Time Experience in Psychosis (STEP). The original English version of the STEP measures different spatial (14 phenomena) and temporal (11 phenomena) phenomena in 25 items. The STEP shows both a high internal consistency (Cronbach's alpha = 0.94) and a significant correlation with the Positive and Negative Syndrome Scale (PANSS; p < 0.001). In summary, the German version of the STEP scale presented here represents an important instrument in the German-speaking countries for the assessment of spatial and temporal experience in patients with psychotic disorders.

Temporal imprecision and phase instability in schizophrenia resting state EEG

Schizophrenia is characterized by temporal imprecision and irregularities on neuronal, psychological cognitive, and behavioral levels which are usually tested during task-related activity. This leaves open whether analogous temporal imprecision and irregularities can already be observed in the brain's spontaneous activity as measured during the resting state; this is the goal of our study. Building on recent task-related data, we, using EEG, aimed to investigate the temporal precision and regularity of phase coherence over time in healthy, schizophrenia, and bipolar disorder participants. To this end, we developed a novel methodology, nominal frequency phase stability (NFPS), that allows to measure stability over phase angles in selected frequencies. By applying sample entropy quantification to the time-series of the nominal frequency phase angle time series, we found increased irregularities in theta activity over a frontocentral electrode in schizophrenia but not in bipolar disorder. We therefore assume that temporal imprecision and irregularity already occur in the brain's spontaneous activity in schizophrenia.

Catatonia: “Fluctuat nec mergitur”

In the beginning of the 1900s, the prevalence of catatonia in inpatient samples was reported to be between 19.5% and 50%. From the mid-1900s, most clinicians thought that catatonia was disappearing. Advances in medical sciences, particularly in the field of neurology, may have reduced the incidence of neurological diseases that present with catatonic features or mitigated their severity. More active pharmacological and psychosocial treatment methods may have either eliminated or moderated catatonic phenomena. Moreover, the relatively narrow descriptive features in modern classifications compared with classical texts and ascribing catatonic signs and symptoms to antipsychotic-induced motor symptoms may have contributed to an apparent decline in the incidence of catatonia. The application of catatonia rating scales introduced in the 1990s revealed significantly more symptoms than routine clinical interviews, and within a few years, the notion of the disappearance of catatonia gave way to its un-expected resurgence. Several systematic investigations have found that, on average, 10% of acute psychotic patients present with catatonic features. In this editorial, the changes in the incidence of catatonia and the possible underlying causes are reviewed.