Hallucinogen persisting perception disorder after psilocybin consumption: a case study

The recurrence of flashbacks without acute or chronic hallucinogen consumption has been recognized in the DSM IV criteria as the hallucinogen persisting perception disorder (HPPD). Perceptual disturbances may last for 5 years or more and represent a real psychosocial distress. We reported here a case of a 18-year-old young man presenting HPPD after a mixed intoxication with psylocibin and cannabis. This report shows symptomatic recurrences persisting more than 8 months. Various differential diagnoses were evoked and our therapeutic strategies were described.

Impairments of executive/attentional functions in schizophrenia with primary and secondary negative symptoms

Frontal cognitive inabilities have been amply described in schizophrenic patients with negative symptoms, but findings are controversial. These discrepancies could be due to the fact that negative symptoms are heterogeneous, composed of primary and secondary negative symptoms. The hypothesis tested was that executive/attentional dysfunctions would be significantly more impaired in patients with primary than in patients with secondary negative symptoms independently of IQ, the severity of negative or positive symptoms, treatments and side effects. Fifty-six DSM-IV schizophrenic patients characterized either by primary or secondary negative symptoms and 56 controls matched on age, sex and level of education were assessed with executive/attentional cognitive tests. The categories score of the Modified Card Sorting Test (MCST) and the Verbal Fluency Test, which reflect solving and organizing skills, were significantly more impaired in the primary negative subtype than in the secondary negative subtype. In contrast, scores on the MCST (perseveration), the Trail Making Test and the Stroop Color Word Test, which test the ability to inhibit an automatic response, did not differ between the two subtypes. In conclusion, this study supports the view that primary and secondary negative symptoms could be associated with different levels of executive/attentional dysfunctions.

Verbal learning and memory in schizophrenic and Parkinson's disease patients

The purpose of this study was to investigate the neurofunctional substrate of verbal learning and memory impairments in schizophrenic patients. In this pilot study, our aim was to compare the memory disturbance of schizophrenic patients to the subcortico-frontal memory profile of Parkinson's disease (PD) patients. The California Verbal Learning Test, a verbal episodic memory test, was administered to 60 subjects, 20 patients with schizophrenia, 20 patients with PD and 20 healthy control subjects. All subjects were aged between 50 and 70 years and all patients were in a stable phase. Like the Parkinson patients, the schizophrenic patients showed a major deficit of retrieval characterized by deficit of recalls but contrarily to PD patients, schizophrenic patients' encoding scores were altered. These impairments in episodic memory could suggest a dysfunction of the subcortico-frontal circuits in schizophrenic patients. However, they demonstrated an additional encoding deficit associated with probable frontal in situ alteration.

Cognitive patterns in subtypes of schizophrenia

AIM

Because of the heterogeneity of schizophrenia, this study researched different cognitive patterns in distinct subtypes of schizophrenic patients.

METHODS

Thirty-five Diagnostic and Statistical Manual IV (DSM IV) schizophrenic patients and 35 healthy controls were included. Patients were categorized into deficit, disorganized and positive subtypes with the schedule for the deficit syndrome (SDS) and the positive and negative syndrome scale (PANSS). Executive/attentional functions were assessed with the modified card sorting test (MCST), a test of verbal fluency, the trail making test (TMT) and the Stroop color-word test (Stroop test). Episodic memory was explored through the California verbal learning test (CVLT).

RESULTS

The positive subtype had some executive/attentional (fluency and Stroop tests) and mnesic performances in the normal range, suggesting the preservation of good cognitive skills. In contrast, the deficit and disorganized subtypes had major mnesic and executive/attentional dysfunctions compared to healthy subjects. The deficit subtype compared to the control group performed predominantly worse on the MCST and fluency, whereas the disorganized subtype had the lowest scores on the TMT and the Stroop test.

CONCLUSION

This study showed distinct cognitive patterns in deficit, disorganized and positive patients in comparison with the controls, suggesting a heterogeneous cognitive dysfunction in schizophrenia.

Executive/attentional cognitive functions in schizophrenic patients and their parents: a preliminary study

The aim of this study was to determine whether executive/attentional cognitive performances could be considered as markers of vulnerability to schizophrenia. The Stroop Color Word and fluency tests were significantly impaired in schizophrenic patients and their parents compared to controls matched on age and sex while performances on Nelson's Modified Card Sorting Test and the Trail Making Test did not differ. The impairments on the Stroop and fluency could be considered as endophenotypic markers of schizophrenia.