Humor appreciation deficit in schizophrenia: the relevance of basic neurocognitive functioning

The purpose in undertaking the present study was to investigate humor appreciation in patients with schizophrenia. Moreover, we sought to explore the potential relationship of humor appreciation with measures of psychopathology and cognitive functioning among the patients. Thirty-six patients with schizophrenia were compared with 31 normal controls matched for age, sex, and education on a computerized test comprising captionless cartoons: Penn's Humor Appreciation Test (PHAT). The patients were also evaluated on the symptom dimensions derived from the Positive and Negative Symptom Scale (positive symptoms, negative symptoms, cognitive symptoms, depression, and excitement), as well as a battery of neuropsychological tests measuring executive functions, attention, working memory, verbal and visual memory, visuospatial ability, and psychomotor speed. Patients with schizophrenia had significantly lower scores on the PHAT than normal controls. The patients' performance on the PHAT correlated with scores on Penn's Continuous Performance Test, the Stroop Color-Word Test, and the phonological subscale of the Greek Verbal Fluency Test. Our findings indicated impaired humor appreciation among patients with schizophrenia. The relationship found between the appreciation of captionless cartoons involved an incongruous detail and performance on a broad neuropsychological battery suggested that the deficit in humor appreciation in schizophrenia could be attributed to impairment in more basic neurocognitive domains, namely, selective and sustained attention as well as phonological word fluency.