Funktionelle Bildgebung des Hippocampus bei Gedächtnisaufgaben und ihr Zusammenhang zu Schizotypie
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Philipps-Universität Marburg
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Abstract
Schizotypy is a multidimensional personality construct that represents susceptibility to psychosis on a continuum between health and illness. It encompasses a range of cognitive, behavioural
and personality traits that are found across the population considered to be mentally healthy.
Schizotypy shows many correlates to schizophrenia spectrum disorders, including shared genetic variations and neurobiological aspects, cognitive deficits, and structural and functional alterations of brain regions. One brain region that shows changes more frequently in mental illness is the hippocampus. It is a brain region that is involved in the encoding of information, the
retrieval of memory content, as well as in declarative and working memory. The disease-associated changes found here can play a role in the genesis of mental illnesses as well as being a
consequence of them.
In the present study cohort, the relationship between schizotypy and hippocampal activation
was investigated in functional magnetic resonance imaging (fMRI) during a memory task. The
study cohort consisted of 761 mentally healthy subjects aged 18 to 65 years, including 262 men
(34.4 %) and 499 women (65.6 %). For the fMRI analyses, a mask (region of interest, ROI) was
used to select the hippocampus for each hemisphere. Schizotypy was assessed using the Schizotypy Personality Questionnaire-Brief (SPQ-B). In addition, the subjective distress caused by psychoticism and paranoid thinking was recorded using the Symptom Checklist-90-Revised (SCL-90R) and the scales were redistributed to the dimensions of Rössler et al. "schizotypal signs (STS)"
and "schizophrenia nuclear symptoms (SNS)". The analyses were conducted separately with the
SCL-90 dimensions psychoticism and paranoid thinking, the Rössler scales SNS and STS, the total
SPQ-B score, as well as the different SPQ-B dimensions cognitive-perceptual, interpersonal and
disorganised. The results were tested for modulating influences in moderation and mediation
analyses. Influences from traumatic experiences in childhood, recorded using the Childhood
Trauma Questionnaire (CTQ), from subclinical depressive symptoms, recorded using Beck's Depression Inventory (BDI), and influences from gender were analysed.
An increased level of schizotypal factors correlated with reduced hippocampal activation in
memory tasks. This was particularly evident in the positive schizotypy dimension (cognitive-perceptual) in the sense of a stable personality component, as well as in an increased burden of
paranoid thoughts and psychoticism as a transient component. Subclinical depressive symptoms
interacted exclusively with increased exposure to psychoticism during hippocampal activation.
Hippocampal functional magnetic resonance imaging activation was significantly related to subclinical depressive symptoms. Furthermore, a gender difference was found in the activation patterns. Men showed an altered overall activation for faces, whereas women showed an altered
specific activation for faces. Overall, hippocampal activation in the fMRI was moderated by gender. Childhood trauma had no significant influence on the functional magnetic resonance imaging activation of the hippocampus.
In total, the results support the construct of schizotypy as a risk factor for psychosis and there
fore reinforces the conceptualization of schizotypy and schizophrenia as existing on a continuum. The functional magnetic resonance imaging activation of the hippocampus was reduced in
higher levels of schizotypy during the memory tasks. The observed hippocampal activation patterns align with previous research indicating that schizotypy shares cognitive and neurobiological characteristics with clinically significant psychotic disorders. The hippocampus therefore
shows changes not only in manifest mental illnesses, but also in their risk stages. However, the
state of research is still very heterogeneous. Future research is necessary to better understand
the complex interplay between genetic predispositions, environmental factors, and cognitive
functions in schizotypy and related psychopathologies.
A standardised homogeneous survey method and definition of schizotypy could lead to clearer
results. Overall, however, higher levels of schizotypy appear to be associated with an altered
structure, connectivity, and activation of various brain regions.
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Dates
Created: 2025Issued: 2025-08-06Updated: 2025-08-06
Faculty
Medizin
Publisher
Philipps-Universität Marburg
Language
ger
Data types
DoctoralThesis
Keywords
schizotypy
DFG-subjects
SchizotypiefMRTHippocampus
DDC-Numbers
610
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Häfner, Marie Sarah: Funktionelle Bildgebung des Hippocampus bei Gedächtnisaufgaben und ihr Zusammenhang zu Schizotypie. : Philipps-Universität Marburg 2025-08-06. DOI: https://doi.org/10.17192/z2025.0414.
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