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Steffen Moritz

Publications and source records attributed to Steffen Moritz.

At least 19 recordsLinked to original sources
PubMed2006

Blockade of the mineralocorticoid receptor in healthy men: effects on experimentally induced panic symptoms, stress hormones, and cognition.

Animal studies have shown that blockade of central mineralocorticoid receptors (MR) has anxiolytic effects and impairs several aspects of cognitive function. No study to date assessed the effects of MR blockade on anxiety and cognitive function in humans. In the present study, 16 healthy young men were treated either with placebo or with 300 mg spironolactone, a MR-antagonist, at 1100, 1330, and 1630 hours in a balanced cross-over design with the two study conditions being 1 week apart. At 1500 hours, the panic symptoms provoking compound cholecystokinin-tetrapeptide (CCK-4) was administered i.v. on both occasions and panic symptoms were assessed. We measured plasma ACTH and cortisol between 1300 and 1900 hours and assessed cognitive function between 1800 and 1900 hours. CCK-4 elicited panic symptoms and increased ACTH and cortisol secretion in both conditions. Intensity of panic symptoms after CCK-4 was not different between spironolactone and placebo. Spironolactone significantly impaired selective attention and delayed recall of visuospatial memory, and diminished set shifting/mental flexibility on a trend level. Pretreatment with spironolactone led to higher baseline cortisol levels compared to placebo whereas no differences in stimulated cortisol, baseline ACTH, and stimulated ACTH emerged. Blockade of MR with spironolactone increases baseline cortisol secretion and impairs cognitive function but has no effect on experimentally induced panic symptoms in humans, for the study design and dosage of spironolactone used. The domains of cognitive function that are impaired after blockade of MR in men, that is, selective attention, visuospatial memory, and mental flexibility/set shifting appear to be remarkably similar to those described in animal studies.

Adrenocorticotropic Hormone↗
PubMed2006

Neural correlates of memory confidence.

The present study aimed to shed light on the neural underpinnings of high vs. low memory confidence. To dissociate memory confidence from accuracy, the Deese-Roediger McDermott (DRM) paradigm was employed, which - compared to other memory paradigms - elicits a rather evenly distributed number of high-confident responses across all possible combinations of memory response types (i.e., hits, false alarms, correct rejections, and misses). In the standard DRM procedure, subjects are first presented with thematically interrelated word lists at encoding, which at recognition are intermixed with related and unrelated distractor items. The signature of a false memory or DRM effect is an increased number of high-confident false memories, particularly for strongly related lure items. For the present study, 17 female subjects were administered a verbal DRM task, whereas neural activation was indexed by fMRI. The behavioral analyses confirmed the expected false memory effect: subjects made more high-confident old responses (both hits and false alarms) the closer the items were related to the central list theme. Across all four memory response types, an increase in confidence at recognition was associated with bilateral activation in the anterior and posterior cingulate cortex along with medial temporal regions. In contrast, increments in doubt were solely related to activation in the superior posterior parietal cortex. To conclude, the study provides some evidence for dissociable systems for confidence and doubt.

Adult↗
PubMed2006

A generalized bias against disconfirmatory evidence in schizophrenia.

Fixation onto false/unrealistic beliefs is a core feature of schizophrenic delusions. A recent study conducted by our research group has provided evidence for the presence of a bias against disconfirmatory evidence (BADE) in patients with schizophrenia. Importantly, this bias was found with delusion-neutral material. To further validate a BADE as an underlying component of schizophrenic delusions, we recruited 34 presently deluded and non-deluded patients with schizophrenia, along with 26 healthy and 46 mixed psychiatric control participants. Participants were administered a closure task. On each trial, a common object (e.g., elephant) was increasingly disambiguated (i.e., shown in decreasing degrees of fragmentation). The participants were required to assess the plausibility of different interpretations at each of the up to eight stages in each trial. In line with the main hypothesis, patients with schizophrenia downgraded the ratings for incorrect interpretations significantly less over the course of task completion than did healthy and psychiatric controls. In contrast, the gradual upgrading of correct interpretations was similar across all groups, suggesting that the pattern of results obtained for incorrect interpretations reflects a BADE and not a mere repetition of prior responses or a lack of attention to the task at hand. The present study suggests that a BADE is a core feature of schizophrenia, and that this style of thinking is not confined to delusion-congruent scenarios.

Adult↗
PubMed2006

Patients with schizophrenia do not produce more false memories than controls but are more confident in them.

BACKGROUND: Patients diagnosed with schizophrenia consistently demonstrate impairment in memory acquisition. However, no empirical consensus has been achieved on whether or not patients are more prone to produce false memories. METHOD: A visual variant of the Deese-Roediger-McDermott (DRM) paradigm was administered to 35 schizophrenia patients and 34 healthy controls. Recognition and recognition confidence were later tested for studied and lure items. Strong contextual cues at recognition encouraged adoption of a gist-based retrieval strategy, which was predicted to elicit over-confidence in errors and increase the false memory rate in patients. RESULTS: Patients were significantly impaired on true item recognition but did not display more false memories than healthy subjects. As predicted from prior findings by our group, patients were more confident than controls for lure items, while being at the same time under-confident for studied items (reduced confidence gap). CONCLUSIONS: Although patients did not produce more false memories than controls, such errors were made with higher confidence relative to controls. The decreased confidence gap in patients is thought to stem from a gist-based recollection strategy, whereby little evidence suffices to make a strong judgment.

Adult↗
PubMed2006

Processing of local and global visual features in obsessive-compulsive disorder.

Research conducted with the Rey-figure task has suggested that patients with obsessive-compulsive disorder (OCD) process local aspects of a complex stimulus more efficiently than the overall gestalt. The aim of the present study was to investigate if this "local bias" is established already during early stimulus encoding or occurs only during later processing, once a percept has been formed (e.g., memory retrieval). To this end, responding to local and global targets of hierarchical letters (e.g., an "E" composed out of small "T"s) was assessed in 30 OCD patients and 28 healthy controls. OCD patients and controls performed comparably on all parameters. These results lend no support to the notion of an early perceptual bias towards local elements in OCD patients. It remains to be tested whether a bias towards local features is confined to situations where local and global features compete for selection.

Adult↗
PubMed2006

Everyday memory functioning in obsessive- compulsive disorder.

Memory performance in obsessive-compulsive disorder (OCD) is discussed as a pathogenetic risk factor for the emergence of OCD, particularly checking compulsions. At present, however, findings are mixed and little is known about memory performance in tasks relevant to everyday functioning in patients with OCD. For the present study, memory performance was assessed in 31 patients diagnosed with OCD and 33 healthy controls with the Rivermead Behavioural Memory Test (RBMT), which covers a wide range of verbal and nonverbal memory components as well as prospective memory. OCD patients performed comparably to healthy controls on the memory task for verbal, nonverbal, and prospective memory (p > .1). According to norm values, memory performance was unimpaired in most OCD patients. The present findings further challenge a broad account of the "memory deficit" hypothesis of OCD and compulsive checking, respectively.

Activities of Daily Living↗
PubMed2006

The contribution of metamemory deficits to schizophrenia.

A number of recent studies have demonstrated that individuals with schizophrenia display knowledge corruption; that is, they hold false information with strong conviction. This aberration in metamemory is thought to stem from poor memory accuracy in conjunction with impaired discrimination of correct and incorrect judgments in terms of confidence. Thirty-one participants with schizophrenia, along with 61 healthy control participants and 48 control participants with other psychiatric conditions, participated in a computerized source memory task. Whereas no differences in memory accuracy were observed between the group with schizophrenia and the group with other psychiatric diagnoses, knowledge corruption was specifically impaired in those with schizophrenia. Schizophrenia participants showed a significantly decreased confidence gap: They were more confident in errors and less confident in correct responses relative to those in the control groups. Knowledge corruption is theorized to be a potential risk factor for the emergence of delusions.

Adult↗
PubMed2006

Increased hindsight bias in schizophrenia.

An underlying theme common to prominent theoretical accounts of cognition in schizophrenia is that information processing is disproportionately influenced by recently/currently encountered information relative to the influence of previously learned information. In this study, the authors tested this account by using the hindsight bias or knew-it-all-along (KIA) paradigm, which demonstrates that newly acquired knowledge influences recall of past events. In line with the account that patients with schizophrenia display a disproportionately strong influence of recently encountered information relative to the influence of previously learned information, patients displayed a KIA effect that was significantly greater than in controls. This result is discussed in the context of the cognitive underpinnings of the KIA effect and delusion formation.

Adult↗
PubMed2006

False beliefs maintenance for fear-related information in obsessive-compulsive disorder: an investigation with the hindsight paradigm.

The present study tested whether participants with obsessive-compulsive disorder (OCD) overestimate the incidence frequency of OCD-relevant phenomena and display a decreased hindsight bias for concern-related information, which may represent a maintenance factor for OCD. Thirty participants with OCD and 39 control participants were requested to estimate the incidence frequency of 8 events in each of 4 domains: washing-relevant, checking-relevant, negative, or neutral. Subsequently, participants received the correct statistics for all items and were requested to affectively appraise these. Two hours later participants had to reproduce their initial estimates. No differences emerged between participants with OCD and control participants regarding initial estimates. In case the frequency of an OCD-relevant item was initially largely overestimated, control participants expressed more relief when confronted with the correct solution than participants with OCD, especially for washing-relevant items. The recalled estimates showed a typical hindsight bias (i.e., the reproduced estimates were biased toward the correct response), but with no difference between groups. In sum, participants were normal in their subjective estimates of OCD-relevant events, and there was no evidence for a heightened maintenance of false beliefs.

Adult↗
PubMed2006

The contribution of a cognitive bias against disconfirmatory evidence (BADE) to delusions in schizophrenia.

A neuropsychological paradigm is introduced that provides a measure of a bias against disconfirmatory evidence (BADE), and its correspondence with delusions in people with schizophrenia and schizoaffective disorder was investigated. Fifty-two patients diagnosed with schizophrenia or schizoaffective disorder (36 were acutely delusional) and 24 healthy control participants were presented with delusion-neutral pictures in each trial, and were asked to rate the plausibility of four written interpretations of the scenario depicted by that picture. Subsequently, new pictures that provided background information about the depicted scenario were successively presented, and participants were requested to adjust their ratings, taking into account this new information. Two of the interpretations appeared tenable initially but ultimately proved to be implausible, one appeared untenable initially but eventually proved to be plausible, and one appeared untenable at all stages. A BADE was observed for delusional compared to non-delusional patients, as well as for all patients compared to controls. In addition, regardless of symptom profile, patients were more accepting of implausible interpretations than controls. The present work suggests that deficits in reasoning may contribute to the maintenance of delusions via an impairment in the processing of disconfirmatory evidence.

Adult↗
PubMed2006

Verbal and nonverbal memory functioning in posttraumatic stress disorder (PTSD).

Although there is evidence for memory impairment in posttraumatic stress disorder (PTSD), it remains unclear whether memory impairment is confined to verbal material or whether memory for nonverbal material is also affected. We examined verbal and nonverbal memory for free recall and recognition in 40 patients with PTSD and 40 healthy controls. Analyses showed that patients with PTSD displayed attenuated memory performance for both short- and long-term recall, which was not further moderated by type of material. The influence of attention, verbal intelligence, and depression was investigated. Our findings suggest that both verbal and nonverbal memory are compromised in PTSD.

Adult↗
PubMed2006

Childhood trauma and dissociation in female patients with schizophrenia spectrum disorders: an exploratory study.

The few studies that have investigated the relationship between trauma and dissociative symptoms in patients with schizophrenia have not assessed the role of the severity of psychotic symptoms. The current study examined correlations among five domains of childhood trauma and dissociative symptoms in 30 female patients with schizophrenia spectrum disorders, using the Dissociative Experiences Scale and the Childhood Trauma Questionnaire. Psychotic symptoms were measured by the Positive and Negative Syndrome Scale. Consistent with previous studies, high levels of childhood traumatic experiences were found (Childhood Trauma Questionnaire total score M = 48.5, SD = 18.3). Physical neglect and emotional abuse showed significant correlations with dissociative symptoms at admission. When patients were stabilized, about a month after admission, emotional abuse still showed a significant correlation with dissociative symptoms. However, in contrast to previous findings, Dissociative Experiences Scale findings were not stable over time. Our results confirm the relevance of childhood trauma in schizophrenic patients but also demonstrate the need to develop appropriate methodologies for measuring dissociation in this population.

Adolescent↗
PubMed2006

Dissociation as a predictor of cognitive behavior therapy outcome in patients with obsessive-compulsive disorder.

BACKGROUND: Previous studies have found a strong association between dissociation and obsessive-compulsive disorder (OCD). The purpose of the present study was to evaluate whether dissociation is a predictor of cognitive behavior therapy (CBT) outcome in patients with OCD. METHODS: Fifty-two patients with OCD were assessed using the Dissociative Experience Scale (DES), the Yale-Brown Obsessive-Compulsive Scale and the Beck Depression Inventory. CBT lasted on average 9.5 weeks and included exposure therapy. RESULTS: Patients who dropped out due to noncompliance had higher baseline DES scores and depression scores compared to the 43 patients (83%) who completed the study. Significant OCD symptom reduction at posttreatment was observed in study completers with a large effect size (d = 1.7). More severe OCD symptoms at posttreatment were associated with higher DES scores at baseline, and treatment nonresponders had significantly higher baseline DES scores compared to responders. These associations with outcome were mainly due to the DES subfactor absorption-imaginative involvement. In regression analyses, higher absorption-imaginative involvement scores at baseline predicted poorer CBT outcome, even after controlling for depressive symptoms, comorbid axis I disorders and concomitant psychotropic drugs. CONCLUSIONS: Results from this preliminary study suggest that higher levels of dissociation (particularly absorption-imaginative involvement) in patients with OCD might predict poorer CBT outcome. If our results can be replicated, treatment outcome might be improved by additional interventions for those patients with OCD who indicate high levels of dissociation, for example by using interventions aimed at improving coping with emotionally stressful situations.

Adult↗
PubMed2005

Incautious reasoning as a pathogenetic factor for the development of psychotic symptoms in schizophrenia.

Previous studies indicate that schizophrenia patients draw decisions more hastily than controls. The aim of the present study was to obtain convergent evidence with a new paradigm, designed after the Who Wants to Be a Millionaire television game show. Thirty-two schizophrenia patients and 38 healthy subjects were administered 20 knowledge questions, along with 4 response alternatives. Participants were required to provide probability estimates for each alternative. Whenever a subject was confident that one of the alternatives was correct or was wrong, the subject was asked to indicate this via a decision or rejection rating. Thus, probability estimates and decisions were independently assessed, allowing determination of the point at which probability estimates translate into decisions. Patients and controls gave comparable probability estimates for all alternatives. However, patients committed more erroneous responses, owing to their making decisions in the face of low subjective probability ratings and rejecting alternatives despite rather high probability ratings. The results provide further evidence for the claim that schizophrenia patients make strong judgments based on little information. We propose that a lowered threshold for accepting alternatives provides a parsimonious explanation for the data-gathering bias reported in the literature.

Adult↗
PubMed2005

Investigation of metamemory dysfunctions in first-episode schizophrenia.

A number of recent studies have suggested that schizophrenia patients share metamemory deficits, particularly, a decreased ability to distinguish between errors and correct responses in terms of response confidence (i.e., decreased confidence gap): patients are over-confident in errors while at the same time being under-confident in responses that are in fact correct. This, along with increased error rates, leads to an inflation of inaccurate but confidently held memories, which has been termed knowledge corruption. Previous studies on metamemory in schizophrenia patients predominantly tested chronic patients, leaving open the possibility that metamemory deficits stem partly from increased chronicity and long-term treatment. The primary aim of the current study was to establish whether a decreased confidence gap is also detectable in first-episode schizophrenia. For this purpose, a source memory task was administered to 30 first-episode patients with a diagnosis of schizophrenia or schizophreniform disorder, and 15 healthy control subjects. During encoding, items were read aloud by the experimenter and the participant in alternating order. For the recognition phase, participants were required to state the source of the item, and their confidence in their response. In agreement with previous studies, the patients displayed a decreased confidence gap, and increased knowledge corruption relative to controls. A reduced distinction between correct and incorrect information in metacognition is proposed to be a vulnerability factor for the development of delusions in schizophrenia.

Acute Disease↗
PubMed2005

A check on the memory deficit hypothesis of obsessive-compulsive checking.

A number of recent studies have challenged the hypothesis that patients with obsessive-compulsive disorder (OCD) display global memory deficits. An alleviated form of the memory deficit hypothesis posits that OCD patients share deficits to vividly recall memory episodes. According to the latter view, checking rituals can be understood as counter-productive coping strategies to "enrich" memory episodes in order to make them more distinctive. A source memory task was administered to 27 OCD (17 checkers) and 51 healthy participants. Along with confidence judgments, a remember-know procedure was employed to assess whether OCD patients display problems with conscious/vivid recollection. Patients with or without checking compulsions did not exhibit differences to controls on source memory accuracy and meta-memory. Patients forgot more self-generated items, which, however, was related to comorbid depressive but not OCD symptoms. Findings challenge the ubiquity of memory deficits in OCD. To account for the inconclusive pattern of results in the literature, it is suggested that patients mistrust their memories and adopt checking rituals only when perceived responsibility is inflated.

Adaptation, Psychological↗
PubMed2005

Do personality disorders predict negative treatment outcome in obsessive-compulsive disorders? A prospective 6-month follow-up study.

BACKGROUND: Comorbid personality disorders (PDs) are discussed as risk factors for a negative treatment outcome in obsessive-compulsive disorder (OCD). However, studies published so far have produced conflicting results. The present study examined whether PDs affect treatment outcome in patients with OCD. METHOD: The treatment sample consisted of 55 patients with OCD who were consecutively referred to a Behaviour Therapy Unit for an in-patient or day-clinic treatment. Treatment consisted of an individualised and multimodal cognitive behaviour therapy (CBT, with or without antidepressive medication). Measurements were taken prior and after treatment and 6-month after admission. RESULTS: A large percentage of patients benefited from treatment irrespective of the presence of a PD and were able to maintain their improvement at follow-up. Duration of treatment was not prolonged in OCD patients with concomitant Axis II disorders. However, some specific personality traits (schizotypal, passive-aggressive) were baseline determinants for later treatment failure at trend level. CONCLUSIONS: Results are encouraging for therapists working with patients co-diagnosed with Axis II disorders since these patients are not necessarily non-responders. The results stress the importance of a specifically tailored treatment approach based on an individual case formulation in OCD patients with complex symptomatology and comorbid Axis II disorders.

Adolescent↗