Minimal Self and Timing Disorders in Schizophrenia: A Case Report

Sex differences in schizophrenia spectrum disorders: insights from the DiAPAson study using a data-driven approach

PURPOSE

Schizophrenia Spectrum Disorders (SSD) display notable sex differences: males have an earlier onset and more severe negative symptoms, while females exhibit affective symptoms, better verbal abilities, and a more favourable prognosis. Despite extensive research, areas such as time perception and positivity remain underexplored, and machine learning has not yet been adequately utilised. This study aims to address these gaps by examining sex differences in a sample of Italian patients with SSD using a data-driven approach.

METHODS

As part of the DiAPAson project, 619 Italian patients with SSD (198 females; 421 males) were assessed using standardised clinical tools. Data on socio-demographics, clinical characteristics, symptom severity, functioning, positivity, quality of life (QoL), and time perspective were collected. Descriptive and regression analyses were conducted. Principal Component Analysis (PCA) and the Gaussian Mixture Model (GMM) was used to define data-driven clusters. A leave-one-group-out validation was performed.

RESULTS

Males were more likely to be single (p < 0.001) and less educated (p = 0.006), while females smoked more tobacco (p = 0.011). Males were more frequently prescribed antipsychotics (p = 0.022) and exhibited more severe psychiatric (p = 0.004) and negative symptoms (p = 0.013). They also had a less negative perception of past events (p = 0.047) and a better view of their psychological condition (p = 0.004). Females showed better interpersonal functioning (p = 0.008). PCA and GMM revealed two main clusters with significant sex differences (p = 0.027).

CONCLUSION

This study identifies sex differences in SSD, suggesting tailored treatments such as enhancing interpersonal skills for females and maintaining positive self-assessment for males. Using machine learning, we highlight distinct SSD phenotypes, emphasising the need for sex-specific interventions to improve outcomes and QoL. Our findings stress the importance of a multifaceted, interdisciplinary approach to address sex-based disparities in SSD.

TRIAL REGISTRATION

ISRCTN registry ID ISRCTN21141466.

Time moving 100-fold slower: time distortion as a diagnostic clue in anti-NMDA receptor encephalitis

BACKGROUND

The primary symptoms in the early stages of anti-NMDA receptor encephalitis are psychiatric manifestations, making it difficult to distinguish from psychiatric disorders. While anti-NMDA receptor encephalitis requires a completely different treatment approach, the specific psychiatric features of the condition remain poorly identified. Although previous studies have suggested that altered perceptions may be characteristic, few case reports focus on altered perceptions of time or time distortion, a phenomenon closely linked to NMDA receptor dysfunction as seen in individuals using NMDA receptor inhibitors like ketamine and phencyclidine. In this report, we describe two cases of anti-NMDA receptor encephalitis manifesting pronounced time distortion in its early stages, which may serve as diagnostic clues for the early diagnosis and treatment of this potentially lethal condition.

CASE PRESENTATIONS

Two cases of Anti-NMDA receptor encephalitis, both marked by significant time distortion in the early stages and showing near-complete recovery with immunotherapy, are presented in detail. In both cases, time distortion was the predominant symptom among the psychiatric manifestations. Case 1: A middle-aged man experienced a pronounced perception of time moving 100 times slower in the early stages, accompanied by feelings of detachment and auditory abnormalities. This time distortion persisted for over a year, even after other symptoms had fully resolved. Case 2: A young woman reported that time seemed to move two to three times slower in the early stages. Although she did not initially mention time distortion, she confirmed it when specifically questioned.

CONCLUSIONS

Our report suggests that time distortion, particularly the perception of time moving slowly, can be a distinguishing feature in the early stages of anti-NMDA receptor encephalitis. This unique characteristic, especially when occurring independently of other symptoms, is rare as a primary and isolated symptom in other conditions, making it useful for differentiation from time distortion in other psychiatric disorders. Additionally, since some patients may not spontaneously report time distortion, actively assessing this symptom during early evaluation could help improve diagnostic accuracy.

Self and time in individuals with schizophrenia: A motor component?

Phenomenology suggests a disruption in the experience of time in individuals with schizophrenia, related to disorders of the sense of self. Patients themselves relate a fragmentation of their temporal experience and of their sense of self. Temporal expectations help relate the present moment to the future and we have previously shown that temporal expectations are fragile in patients, and relate to disorders of the self. Here, we investigate whether patients' performance is still impaired when the motor response to the expected event can be prepared in advance. In two different experiments participants (41 patients vs. 43 neurotypicals in total) responded to a visual target occurring at a variable interval (or "foreperiod") after an initial warning signal. Moreover, in Experiment 1 we measured the sense of self with the EASE scale. We observed the usual benefit of the passage of time: the longer the waiting period, the better the preparation, and the faster the responses. However, this effect also comprises sequential (surprise) effects, when a target occurs earlier than on the preceding trial. We evaluated the effect of the passage of time, by isolating trials that followed a trial with the same foreperiod. The benefit of long, versus short, foreperiods was still observed in controls but disappeared in patients. The results suggest that the benefit of the passage of time is diminished in patients and relates to self disorders, even when the task allows for motor preparation. The results suggest that a non-verbal impairment sub-tends disorders of the sense of self.

Inattentive Perception, Time, and the Incomprehensibility of Consciousness

Cerebral energy supply is insufficient to support continuous neuronal processing of the plethora of time-constant objects that we are aware of. As a result, the brain is forced to limit processing resources to (the most relevant) cases of change. The neuronally generated world is thus temporally discontinuous. This parallels the fact that, in all relevant microscopic fundamental equations of nature, temporal change plays a dominant role. When a scientist calculates a "solution" to such an equation, integration over time is an essential step. The present Hypothesis expresses that the step from neuronal activity to phenomenal content of consciousness is reflective of a (phenomenal) "solution:" the main source of the incomprehensibility of consciousness is proposed to result from the introduction of phenomenal time-constant entities. These are "filled-in" via integration, even though neuronal data only exists for changes to these entities. In this way, a temporally continuous picture of the world phenomenally appears. Qualia are "initial conditions," which are required for integration and cannot be deduced from present data. Phenomenal "identity" (vs. "high similarity") is related to qualia. Inattentive visual perception, which is only rarely investigated, offers insights into these relationships. Introspectively, unattended vision appears rich because percepts are cumulated over long time spans, whereas attentive perception relies purely on present neuronal signals. The present Hypothesis is that a brief neuronal activity can signify long-lasting and constant phenomenal content of consciousness. Experimental support is presented that comes from discrepancies between neuronal activity and perception: transient neuronal responses to sustained stimuli, "filling-in," change blindness, identity vs. close resemblance.

Time experience in patients with schizophrenia and affective disorders

Background

The experience of time, or the temporal order of external and internal events, is essential for humans. In psychiatric disorders such as depression and schizophrenia, impairment of time processing has been discussed for a long time.

Aims

In this explorative pilot study, therefore, the subjective time feeling as well as objective time perception were determined in patients with depression and schizophrenia, along with possible neurobiological correlates.

Methods

Depressed (n = 34; 32.4 ± 9.8 years; 21 men) and schizophrenic patients (n = 31; 35.1 ± 10.7 years; 22 men) and healthy subjects (n = 33; 32.8 ± 14.3 years; 16 men) were tested using time feeling questionnaires, time perception tasks and critical flicker-fusion frequency (CFF) and loudness dependence of auditory evoked potentials (LDAEP) to determine serotonergic neurotransmission.

Results

There were significant differences between the three groups regarding time feeling and also in time perception tasks (estimation of given time duration) and CFF (the “DOWN” condition). Regarding the LDAEP, patients with schizophrenia showed a significant negative correlation to time experience in terms of a pathologically increased serotonergic neurotransmission with disturbed time feeling.

Conclusions

Impairment of time experience seems to play an important role in depression and schizophrenia, both subjectively and objectively, and novel neurobiological correlates have been uncovered. It is suggested, therefore, that alteration of experience of time should be increasingly included in the current psychopathological findings.

Scale for Space and Time Experience in Psychosis: Converging Phenomenological and Psychopathological Perspectives

INTRODUCTION

Abnormalities in the experience of space and time are fundamental to understanding schizophrenia spectrum disorders, but the precise relation between such abnormalities and psychopathological symptoms is still unclear. Therefore, the aim of our study was to introduce a novel scale for space and time experience in psychosis (STEP), specifically devised to assess schizophrenia spectrum disorders.

METHODS

The STEP scale is a semiquantitative instrument developed on the basis of several items from previous scales and phenomenological reports addressing the experience of space and time. We applied the STEP scale to three groups of subjects (patients with schizophrenia spectrum disorders, patients with predominant affective symptoms, and healthy control subjects), to whom we also applied other more general psychopathological scales, such as the Positive and Negative Syndrome Scale and the Ego-Psychopathology Inventory.

RESULTS

Patients with schizophrenia spectrum disorders scored significantly higher on general psychopatho<X00_Del_TrennDivis>--</X00_Del_TrennDivis>logical scales relative to subjects belonging to the other groups. The STEP scale provided good psychometric properties regarding reliability. We also tested convergent and divergent validity of the STEP scale and found that space and time subscale scores of STEP significantly correlated with each other, as well as with the remaining general psychopathological scores.

DISCUSSION/CONCLUSION

We introduced the STEP scale as a novel instrument for the assessment of experience of space and time. Its psychometric properties showed high validity and reliability to identify psychopathological symptoms and enabled to differentiate patients with predominantly psychotic symptoms from those with predominantly affective symptoms. The STEP scale provides a standardized measure for assessing disturbances in the experience of space and time. Furthermore, it probably represents a leap forward toward the establishment of an additional dimension of symptoms proposed as "spatiotemporal psychopathology."

Integrating clinical staging and phenomenological psychopathology to add depth, nuance, and utility to clinical phenotyping: a heuristic challenge

Psychiatry has witnessed a new wave of approaches to clinical phenotyping and the study of psychopathology, including the US National Institute of Mental Health's Research Domain Criteria, clinical staging, network approaches, the Hierarchical Taxonomy of Psychopathology, the general psychopathology factor, and a revival of interest in phenomenological psychopathology. The question naturally emerges about what the relationship between these new approaches is. Are they mutually exclusive and competing approaches, or can they be integrated in some way and be used to enrich each other? In this Personal View, we propose a possible integration between clinical staging and phenomenological psychopathology. Domains identified in phenomenological psychopathology (eg, selfhood, embodiment, and affectivity) can be overlaid on clinical stages to enrich and deepen the phenotypes captured in clinical staging (creating high-resolution clinical phenotypes). This approach might be useful both ideographically and nomothetically, to complement diagnosis, enrich clinical formulation, inform treatment of individual patients, and help to guide aetiology research, prediction of clinical trajectory and treatment. Overlaying phenomenological domains on clinical stages might require reformulating these domains in dimensional rather than categorial terms. This integrative project requires assessment tools (some of which are already available) that are sufficiently sensitive and thorough to pick up on the range of relevant psychopathology. The proposed approach offers opportunities for mutual enrichment: clinical staging might be enriched by introducing greater depth to phenotypes; phenomenological psychopathology might be enriched by introducing stages of severity and disorder progression to phenomenological analysis.

When the World Breaks Down: A 3-Stage Existential Model of Nihilism in Schizophrenia

The existential crisis of nihilism in schizophrenia has been reported since the early days of psychiatry. Taking first-person accounts concerning nihilistic experiences of both the self and the world as vantage point, we aim to develop a dynamic existential model of the pathological development of existential nihilism. Since the phenomenology of such a crisis is intrinsically subjective, we especially take the immediate and pre-reflective first-person perspective's (FPP) experience (instead of objectified symptoms and diagnoses) of schizophrenia into consideration. The hereby developed existential model consists of 3 conceptualized stages that are nested into each other, which defines what we mean by existential. At the same time, the model intrinsically converges with the phenomenological concept of the self-world structure notable inside our existential framework. Regarding the 3 individual stages, we suggest that the onset or first stage of nihilistic pathogenesis is reflected by phenomenological solipsism, that is, a general disruption of the FPP experience. Paradigmatically, this initial disruption contains the well-known crisis of common sense in schizophrenia. The following second stage of epistemological solipsism negatively affects all possible perspectives of experience, that is, the first-, second-, and third-person perspectives of subjectivity. Therefore, within the second stage, solipsism expands from a disruption of immediate and pre-reflective experience (first stage) to a disruption of reflective experience and principal knowledge (second stage), as mirrored in abnormal epistemological limitations of principal knowledge. Finally, the experience of the annihilation of healthy self-consciousness into the ultimate collapse of the individual's existence defines the third stage. The schizophrenic individual consequently loses her/his vital experience since the intentional structure of consciousness including any sense of reality breaks down. Such a descriptive-interpretative existential model of nihilism in schizophrenia may ultimately serve as input for future psychopathological investigations of nihilism in general, including, for instance, its manifestation in depression.

Time Distortions: A Systematic Review of Cases Characteristic of Alice in Wonderland Syndrome

Of the perceptual distortions characteristic of Alice in Wonderland syndrome, substantial alterations in the immediate experience of time are probably the least known and the most fascinating. We reviewed original case reports to examine the phenomenology and associated pathology of these time distortions in this syndrome. A systematic search in PubMed, Ovid Medline, and the historical literature yielded 59 publications that described 168 people experiencing time distortions, including 84 detailed individual case reports. We distinguished five different types of time distortion. The most common category comprises slow-motion and quick-motion phenomena. In 39% of all cases, time distortions were unimodal in nature, while in 61% there was additional involvement of the visual (49%), kinaesthetic (18%), and auditory modalities (14%). In all, 40% of all time distortions described were bimodal in nature and 19% trimodal, with 1% involving four modalities. Underlying neurological mechanisms are varied and may be triggered by intoxications, infectious diseases, metabolic disorders, CNS lesions, paroxysmal neurological disorders, and psychiatric disorders. Bizarre sensations of time alteration-such as time going backwards or moving in circles-were mostly associated with psychosis. Pathophysiologically, mainly occipital areas appear to be involved, although the temporal network is widely disseminated, with separate component timing mechanisms not always functioning synchronously, thus occasionally creating temporal mismatches within and across sensory modalities (desynchronization). Based on our findings, we propose a classification of time distortions and formulate implications for research and clinical practice.

The minimal self hypothesis

For millennia self has been conjectured to be necessary for consciousness. But scant empirical evidence has been adduced to support this hypothesis. Inconsistent explications of "self" and failure to design apt experiments have impeded progress. Advocates of phenomenological psychiatry, however, have helped explicate "self," and employed it to explain some psychopathological symptoms. In those studies, "self" is understood in a minimalist sense, sheer "for-me-ness." Unfortunately, explication of the "minimal self" (MS) has relied on conceptual analysis, and applications to psychopathology have been hermeneutic, allowing for many degrees of interpretive latitude. The result is that MS's current scientific status is analogous to that of the "atom," at the time when "atom" was just beginning to undergo transformation from a philosophical to a scientific concept. Fortunately, there is now an opportunity to promote a similar transformation for "MS." Discovery of the brain's Default Mode Network (DMN) opened the door to neuroimaging investigations of self. Taking the DMN and other forms of intrinsic activity as a starting point, an empirical foothold can be established, one that spurs experimental research and that enables extension of research into multiple phenomena. New experimental protocols that posit "MS" can help explain phenomena hitherto not thought to be related to self, thereby hastening development of a mature science of self. In particular, targeting phenomena wherein consciousness is lost and recovered, as in some cases of Unresponsive Wakefulness Syndrome (UWS), allow for design of neuroimaging probes that enable detection of MS during non-conscious states. These probes, as well as other experimental protocols applied to NREM Sleep, General Anesthesia (GA), and the waking state, provide some evidence to suggest that not only can self and consciousness dissociate, MS might be a necessary precondition for conscious experience. Finally, these findings have implications for the science of consciousness: it has been suggested that "levels of consciousness" (LoC) is not a legitimate concept for the science of consciousness. But because we have the conceptual and methodological tools with which to refine investigations of MS, we have the means to identify a possible foundation-a bifurcation point-for consciousness, as well as the means by which to measure degrees of distance from that foundation. These neuroimaging investigations of MS position us to better assess whether LoC has a role to play in a mature science of consciousness.

Temporal integration as "common currency" of brain and self-scale-free activity in resting-state EEG correlates with temporal delay effects on self-relatedness

The self is a multifaceted phenomenon that integrates information and experience across multiple time scales. How temporal integration on the psychological level of the self is related to temporal integration on the neuronal level remains unclear. To investigate temporal integration on the psychological level, we modified a well-established self-matching paradigm by inserting temporal delays. On the neuronal level, we indexed temporal integration in resting-state EEG by two related measures of scale-free dynamics, the power law exponent and autocorrelation window. We hypothesized that the previously established self-prioritization effect, measured as decreased response times or increased accuracy for self-related stimuli, would change with the insertion of different temporal delays between the paired stimuli, and that these changes would be related to temporal integration on the neuronal level. We found a significant self-prioritization effect on accuracy in all conditions with delays, indicating stronger temporal integration of self-related stimuli. Further, we observed a relationship between temporal integration on psychological and neuronal levels: higher degrees of neuronal integration, that is, higher power-law exponent and longer autocorrelation window, during resting-state EEG were related to a stronger increase in the self-prioritization effect across longer temporal delays. We conclude that temporal integration on the neuronal level serves as a template for temporal integration of the self on the psychological level. Temporal integration can thus be conceived as the "common currency" of neuronal and psychological levels of self.

Time Processing, Interoception, and Insula Activation: A Mini-Review on Clinical Disorders

Time processing is a multifaceted skill crucial for managing different aspects of life. In the current work, we explored the relationship between interoception and time processing by examining research on clinical models. We investigated whether time processing deficits are associated with dysfunction of the interoceptive system and/or insular cortex activity, which is crucial in decoding internal body signaling. Furthermore, we explored whether insular activation predicts the subjective experience of time (i.e., the subjective duration of a target stimulus to be timed). Overall, our work suggests that alteration of the interoceptive system could be a common psychophysiological hallmark of mental disorders affected by time processing deficits.

The Self and Its Prolonged Intrinsic Neural Timescale in Schizophrenia

Schizophrenia (SCZ) can be characterized as a basic self-disorder that is featured by abnormal temporal integration on phenomenological (experience) and psychological (information processing) levels. Temporal integration on the neuronal level can be measured by the brain's intrinsic neural timescale using the autocorrelation window (ACW) and power-law exponent (PLE). Our goal was to relate intrinsic neural timescales (ACW, PLE), as a proxy of temporal integration on the neuronal level, to temporal integration related to self-disorder on psychological (Enfacement illusion task in electroencephalography) and phenomenological (Examination of Anomalous Self-Experience [EASE]) levels. SCZ participants exhibited prolonged ACW and higher PLE during the self-referential task (Enfacement illusion), but not during the non-self-referential task (auditory oddball). The degree of ACW/PLE change during task relative to rest was significantly reduced in self-referential task in SCZ. A moderation model showed that low and high ACW/PLE exerted differential impact on the relationship of self-disorder (EASE) and negative symptoms (PANSS). In sum, we demonstrate abnormal prolongation in intrinsic neural timescale during self-reference in SCZ including its relation to basic self-disorder and negative symptoms. Our results point to abnormal relation of self and temporal integration at the core of SCZ constituting a "common currency" of neuronal, psychological, and phenomenological levels.

A reflection upon methods to explore timing in patients with schizophrenia

Phenomenologists have provided a detailed description of the disorders of the subjective experience associated with minimal-self disorders in patients with schizophrenia. Those patients report a range of distortions of their conscious experiences, including a sense of inner void, confusion between self and others, and, sometimes, a disruption of the sense of time. These reports have been interpreted as distortion of the first-person perspective and a lack of immersion in the world, associated with a breakdown of the temporal structure of consciousness, and especially a disruption of the sense of time continuity. Further, it has been proposed that these disruptions are based on a difficulty to retain past information and to predict future information, that is, the mechanisms that help to relate events with one another and to reach a sense of time continuity. Experimental psychology results seem to converge to similar conclusions, inasmuch as some results in patients with schizophrenia suggest a deficient ability to predict sequences of events at the millisecond level. Several studies have underlined this convergence. Here we reflect on the limits of both the phenomenological and experimental psychology approaches, and of the convergence of their hypotheses. We think that this reflection is necessary to avoid premature conclusions on the mechanisms underlying the impairments in patients, but also to enrich our understanding of schizophrenia.