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Recent concepts have highlighted the role of the hippocampus and adjacent medial temporal lobe (MTL) in positive symptoms like delusions in schizophrenia. In healthy individuals, the MTL is critically involved in the detection and... more
Recent concepts have highlighted the role of the hippocampus and adjacent medial temporal lobe (MTL) in positive symptoms like delusions in schizophrenia. In healthy individuals, the MTL is critically involved in the detection and encoding of novel information. Here, we aimed to investigate whether dysfunctional novelty processing by the MTL might constitute a potential neural mechanism contributing to the pathophysiology of delusions, using functional magnetic resonance imaging (fMRI) in 16 unmedicated patients with paranoid schizophrenia and 20 age-matched healthy controls. All patients experienced positive symptoms at time of participation. Participants performed a visual target detection task with complex scene stimuli in which novel and familiar rare stimuli were presented randomly intermixed with a standard and a target picture. Presentation of novel relative to familiar images was associated with hippocampal activation in both patients and healthy controls, but only healthy c...
First rank symptoms (FRS) of schizophrenia have been used for decades for diagnostic purposes. In the new version of the DSM-5, the American Psychiatric Association (APA) has abolished any further reference to FRS of schizophrenia and... more
First rank symptoms (FRS) of schizophrenia have been used for decades for diagnostic purposes. In the new version of the DSM-5, the American Psychiatric Association (APA) has abolished any further reference to FRS of schizophrenia and treats them like any other "criterion A" symptom (e.g. any kind of hallucination or delusion) with regard to their diagnostic implication. The ICD-10 is currently under revision and may follow suit. In this review, we discuss central points of criticism that are directed against the continuous use of first rank symptoms (FRS) to diagnose schizophrenia. We describe the specific circumstances in which Schneider articulated his approach to schizophrenia diagnosis and discuss the relevance of his approach today. Further, we discuss anthropological and phenomenological aspects of FRS and highlight the importance of self-disorder (as part of FRS) for the diagnosis of schizophrenia. Finally, we will conclude by suggesting that the theory and rationa...
ZusammenfassungArchitektur leistet einen wesentlichen Beitrag zur Gestaltung des therapeutischen Milieus in der Soteria. Die Soteria Berlin entstand durch Umbau einer ehemaligen internistischen Station auf dem Gelände des St. Hedwig... more
ZusammenfassungArchitektur leistet einen wesentlichen Beitrag zur Gestaltung des therapeutischen Milieus in der Soteria. Die Soteria Berlin entstand durch Umbau einer ehemaligen internistischen Station auf dem Gelände des St. Hedwig Krankenhauses in Berlin-Mitte. Es wird beschrieben, wie durch gezielte Änderungen des Grundrisses, sorgfältige Auswahl von Materialien, Verwendung von Krankenhaus-untypischer Möblierung sowie durchdachter Farbgestaltung eine wohnliche, einladende und entspannende Umgebung geschaffen wurde, die kaum noch an eine Klinikstation denken lässt. Anstelle der Fokussierung auf bloße Funktion wird hier die Architektur zum Teil des therapeutischen Konzeptes: Atmosphäre als Therapeutikum.
The sense of agency and its neurocognitive underpinnings have been the subjects of increasing attention over the last several years, but their detailed mechanisms remain controversial. An excellent opportunity to investigate both the... more
The sense of agency and its neurocognitive underpinnings have been the subjects of increasing attention over the last several years, but their detailed mechanisms remain controversial. An excellent opportunity to investigate both the basic neurocognitive mechanisms of self-agency attribution and their pathological dysfunctions is to study abnormalities of the sense of agency in neurological or psychiatric patients. In particular, disturbances of agency processing in schizophrenia patients with delusions of influence might reveal specific central mechanisms for the self-attribution of agency, which can be specifically impaired. Patients with delusions of influence feel that someone else is guiding and executing their actions, even if the action is actually completely caused by themselves.
... time of flight measurement.," Phys. Med. Biol. 33, 1433-1442 (1988). 8. Kohl, M., Buckow, C., Zank, H., Obrig, H., Steinbrink, J., and Villringer, A. Topographic Imaging of Cortical Activation. Maniewski, R., Nilsson, G., and... more
... time of flight measurement.," Phys. Med. Biol. 33, 1433-1442 (1988). 8. Kohl, M., Buckow, C., Zank, H., Obrig, H., Steinbrink, J., and Villringer, A. Topographic Imaging of Cortical Activation. Maniewski, R., Nilsson, G., and Rinneberg ...
... 37.3 Bildgebende Untersuchungen neuropsychologischer Erklärungsmodelle – 476 37.3.1 Wahnstimmung und Wahnwahrnehmungen – 476 37.3.2 Kognitive Bias – 476 37.3.3 Verfolgungs-und Beeinflussungswahn als »Theory of Mind«-Störung – 479 ...
Sense of agency (SoAg)--the experience of controlling one's own actions and their consequences--has been studied in schizophrenia but not in the earlier stages of the disease, i.e. in patients with a putative psychotic prodrome (PP).... more
Sense of agency (SoAg)--the experience of controlling one's own actions and their consequences--has been studied in schizophrenia but not in the earlier stages of the disease, i.e. in patients with a putative psychotic prodrome (PP). Previous research has shown that time judgments of voluntary actions can provide an implicit measure of the SoAg. 30 PP patients and 30 healthy controls performed voluntary key presses while watching a rotating clock hand on a monitor. After each key press they had to estimate the time of the action (based on the perceived position of the clock hand at the time of the key press). By varying the probability with which the simple manual action was followed by a tone, we investigated whether shifts in perceptual estimates of the operant action towards a resulting effect depended on the actual occurrence of the effect (retrospective process) or on the prediction that the effect will occur. PP patients differed from healthy controls but their results did...
We studied an amputee patient who experiences a conscious sense of movement (SoM) in her phantom hand, without significant activity in remaining muscles, when transcranial magnetic stimulation (TMS) is applied at appropriate intensity... more
We studied an amputee patient who experiences a conscious sense of movement (SoM) in her phantom hand, without significant activity in remaining muscles, when transcranial magnetic stimulation (TMS) is applied at appropriate intensity over the corresponding sector of contralateral motor cortex. We used the novel methodological combination of TMS during fMRI to reveal the neural correlates of her phantom SoM. A critical contrast concerned trials at intermediate TMS intensities: low enough not to produce overt activity in remaining muscles; but high enough to produce a phantom SoM on approximately half such trials. Comparing trials with versus without a phantom SoM reported phenomenally, for the same intermediate TMS intensities, factored out any non-specific TMS effects on brain activity to reveal neural correlates of the phantom SoM itself. Areas activated included primary motor cortex, dorsal premotor cortex, anterior intraparietal sulcus, and caudal supplementary motor area, regions that are also involved in some hand movement illusions and motor imagery in normals. This adds support to proposals that a conscious sense of movement for the hand can be conveyed by activity within corresponding motor-related cortical structures.
Dopamine dysfunction is a mainstay of theories aimed to explain the neurobiological correlates of schizophrenia symptoms, particularly positive symptoms such as delusions and passivity phenomena. Based on studies revealing dopamine... more
Dopamine dysfunction is a mainstay of theories aimed to explain the neurobiological correlates of schizophrenia symptoms, particularly positive symptoms such as delusions and passivity phenomena. Based on studies revealing dopamine dysfunction in addiction research, it has been suggested that phasic or chaotic firing of dopaminergic neurons projecting to the (ventral) striatum attribute salience to otherwise irrelevant stimuli and thus contribute to delusional mood and delusion formation. Indeed, several neuroimaging studies revealed that neuronal encoding of usually irrelevant versus relevant stimuli is blunted in unmedicated schizophrenia patients, suggesting that some stimuli that are irrelevant for healthy controls acquire increased salience for psychotic patients. However, salience attribution per se may not suffice to explain anxieties and feelings of threat that often accompany paranoid ideation. Here, we suggest that beyond ventral striatal dysfunction, dopaminergic dysregul...
Various factors contribute to the development and maintenance of delusions in the context of schizophrenic psychoses. Studies with functional and structural MRI were able to detect neurobiological correlates of paranoid symptoms.... more
Various factors contribute to the development and maintenance of delusions in the context of schizophrenic psychoses. Studies with functional and structural MRI were able to detect neurobiological correlates of paranoid symptoms. Consistent with the neurodevelopmental hypothesis of schizophrenic psychosis, which implies an early developmental disorder affecting temporo-limbic areas and resulting in a disinhibition of striatal dopamine release, current imaging studies point towards the involvement of temporo-limbic and frontal dysfunction in delusion formation. In line with this, a specific role of dopamine as a neuromodulator in delusion formation is being discussed. Finally, mechanisms relevant to delusion formation appear to involve cognitive processes such as biases of attribution with regard to emotionally salient events as well as attentional biases during the perception of affective stimuli.
Introduction: Wilson’s disease is a rare autosomal recessive disorder of hepatic copper transport leading to a biliary excretion inhibition of copper. Overload of the metal mainly in liver and basal ganglia leads to hepatic, but also to... more
Introduction: Wilson’s disease is a rare autosomal recessive disorder of hepatic copper transport leading to a biliary excretion inhibition of copper. Overload of the metal mainly in liver and basal ganglia leads to hepatic, but also to extrapyramidal motor clinical symptoms. However, involvement of the corticospinal system is hardly known. Methods: To study corticospinal tract dysfunction in Wilson’s disease, motor-evoked potentials (MEP) were performed in 42 patients (14 with a non-neurological and 28 with a neurological form) with Wilson’s disease undergoing long-term treatment. Fwave method was used to determine the central motor latency of the corticospinal pathway. Results were determined and compared with laboratory reference values of a group of 40 healthy persons. Results: In more than half of the patients with a neurological form of Wilson’s disease, abnormalities with delayed latencies and significant reductions of MEP amplitudes occurred. However, also in patients with the non-neurological form prolonged latencies were found. There was no evidence for cerebrovascular nor major spinal disease. Discussion: MEP are useful in monitoring and differential diagnosis of patients with Wilson’s disease. They might predict a deterioration of a non-neurological into a neurological form of this complex disorder.
High-frequency repetitive transcranial magnetic stimulation over the hand area of the primary motor cortex disturbs predictive grip force scaling
Humans and other primates demonstrate an exquisite ability to precisely shape their hand when reaching out to grasp an object. Here we used a recently developed transcranial magnetic stimulation paradigm to examine how information about... more
Humans and other primates demonstrate an exquisite ability to precisely shape their hand when reaching out to grasp an object. Here we used a recently developed transcranial magnetic stimulation paradigm to examine how information about an object's geometric properties is transformed into specific motor programs. Pairs of transcranial magnetic stimulation pulses were delivered at precise intervals to detect changes in the excitability of cortico-cortical inputs to motor cortex when subjects prepared to grasp different objects. We show that at least 600 ms before movement, there is an enhancement in the excitability of these inputs to the corticospinal neurons projecting from motor cortex to the specific muscles that will be used for the grasp. These changes were object- and muscle-specific, and the degree of modulation in the inputs was correlated with the pattern of muscular activity used later by individual subjects to grasp the objects. In a number of control experiments, we ...