Pseudoaneurysm of the Left Ventricle

Abstract: A case study is reported of a patient with rheumatoid arthritis who developed a pseudoaneurysm of the left ventricle after inferior myocardial infarction. The clinical diagnosis was confirmed by radionuclide cardiac blood pool imaging and by contrast ventricu-lography; the aneurysm was successfully excised.     

TEMPORALLY GRADED SEMANTIC MEMORY LOSS IN ALZHEIMER'S DISEASE: CROSS-SECTIONAL AND LONGITUDINAL STUDIES

Abstract

Semantic knowledge of famous names and words that entered popular North American culture at different times in the 20th century was examined in 16 patients with mild-to-moderate Alzheimer's disease (AD), 12 of whom were re-tested 1 year later. All patients showed evidence of temporally graded memory loss, with names and words from the remote past being relatively better preserved than recent names and words. There was considerable between-patient variability with respect to severity of semantic impairment. Most patients exhibited losses extending back 30-40 years; however, two mildly impaired (MMSE >28) patients showed deficits restricted to the last 10-15 years. At the 1-year follow-up, patients not only exhibited more severe deficits overall, but the temporally graded period of loss extended further back in time, suggesting that this deficit reflects a loss of previously intact knowledge and not merely faulty encoding or lack of exposure to the material. The extensive period of graded semantic loss exhibited by most patients contrasts with the temporally limited retrograde semantic loss typical of medial temporal lobe amnesia. We propose that short periods of temporally graded semantic memory loss can be explained by damage to medial temporal structures, but that extensive periods of graded loss occur only with additional damage to neocortical tissue. This pattern contrasts with that of autobiographical memory loss, which is often ungraded and extends for the person's entire lifetime, even when damage is restricted to the medial temporal lobes.     

“That's not my arm”: A hypnotic analogue of somatoparaphrenia

Introduction. “Instrumental hypnosis” allows researchers to model clinical symptoms in the laboratory, creating “virtual patients” with reversible disturbances in, for example, perception, action, memory, or belief. We used hypnosis to temporarily recreate somatoparaphrenia, a delusional belief that one's own limb belongs to someone else.

Methods. We compared a “Fully Formed” somatoparaphrenia suggestion with a “Factor 1 + Factor 2” suggestion that attempted to generate the delusional belief from analogues of its hypothesised underlying factors (i.e., paralysis plus disrupted critical belief evaluation). We tested and then challenged subjects’ responses to these suggestions.

Results. Although many hypnotic subjects experienced temporary paralysis, only a minority claimed their arm did not belong to them. Notably, the Fully Formed suggestion was more successful in recreating features of somatoparaphrenia than the Factor 1 + Factor 2 suggestion. In response to the challenges, some of those who developed temporary somatoparaphrenia maintained their belief throughout the hypnosis session.

Conclusions. We discuss these findings in terms of the “two-factor” theory of delusions and we highlight the advantages versus disadvantages of using hypnosis to explore such delusional beliefs in the laboratory.     

Jumping to delusions? Paranoia,probabilistic reasoning,and need for closure

Introduction. The present study was designed to replicate and extend the findings of Bentall and Swarbrick (2003). It was hypothesised that patients with a history of persecutory delusions would display higher need for closure and a more extreme jumping to conclusions bias than healthy control participants.

Methods. Twenty-two patients with a history of persecutory delusions and nineteen healthy control participants were administered a probabilistic reasoning task, along with self-report measures of depression and need for closure.

Results. The clinical group scored higher on need for closure than the controls, but showed no greater tendency to jump to conclusions. No relationship was found between need for closure and a jumping to conclusions bias.

Conclusions. The results confirm an association between persecutory delusions and need for closure, yet suggest that persecutory delusions in an outpatient sample can be seen in the absence of a jumping to conclusions bias.     

Defective Self and/or Other Mentalising in Schizophrenia: A Cognitive Neuropsychological Approach

The mentalising abilities of schizophrenic patients and normal controls were tested using picture sequencing and story-telling tasks that required subjects to infer causal mental states in story characters, and a recall task that required subjects to dissociate subjective mental states from objective realities. Selective mentalising deficits were found in some patients. For other patients, general sequencing errors, “sensory” mentalising, and poor recall of symbolic representations suggested more profound problems. Task results were best accounted for by dissociable cognitive abnormalities, rather than graded dysfunction of a central mentalising mechanism. Symptom profiles of patient subgroups and correlations between task measures and clinical ratings linked these cognitive abnormalities to specific symptoms. General sequencing difficulty was associated with both poverty symptoms and reality distortion, suggesting that two mechanisms may underpin such errors: one, inability to manipulate symbolic representations, being linked to poverty; the other, failure to critically evaluate plausible cause-and-effect, being linked to reality distortion. There was some evidence that defective self-monitoring underpins thought disorder. Impaired metarepresentation was linked to the autisticlike symptoms of flat affect, social dysfunction, and alogia, rather than reality distortion. Implications of these findings are discussed with respect to theoretical and methodological issues confronting current schizophrenia research.