Deficits in metaphor but not in idiomatic processing are related to verbal hallucinations in patients with psychosis.
There is scant evidence that the verbal cognitive deficits observed in patients with psychosis are related to auditory verbal hallucinations. The understanding of metaphors and idiomatic expressions was investigated in a cohort of 90 patients with active psychosis, and in 44 healthy controls. The Psychotic Symptom Rating Scales (PSYRATS: verbal hallucinations subscale) was used to measure the current verbal hallucinations episode; a subscore of the Launay-Slade Hallucination Scale was used to measure long-term propensity to auditory verbal hallucination-like experiences (HLEs) in the sample. The concurrent influence of education, IQ, and cognitive functioning in memory, attention, fluency, and processing speed on metaphor and idioms processing was investigated. Patients performed worse than healthy controls on all neuropsychological measures. Metaphor, but not idioms processing was poorer in patients with verbal hallucinations (n=46) when compared to patients without verbal hallucinations in the current episode (n=44). By taking into account confounding variables, the ability to produce explanations of metaphors was related to scores on the verbal HLEs in the whole sample of patients. Metaphor-comprehension deficit was related to the occurrence of auditory verbal hallucinations in patients with psychosis, suggesting that abnormal pragmatic inferential abilities have an impact on the mechanisms that cause hallucinatory experiences.
Section of Clinical Psychology, Department of Education, Psychology, and Philosophy, University of Cagliari, Italy; Research and Development Unit, Parc Sanitari Sant Joan de Déu, Sant Boi de Llobregat, Spain, CIBERSAM; Faculty of Medicine, University of Barcelona, Spain. Electronic address: sara.siddi@pssjd.org.
Sara
S
Siddi
Section of Clinical Psychology, Department of Education, Psychology, and Philosophy, University of Cagliari, Italy.
Donatella Rita
DR
Petretto
Section of Clinical Psychology, Department of Education, Psychology, and Philosophy, University of Cagliari, Italy.
Rosanna
R
Scanu
Psychiatric Diagnosis and Treatment Service I, Department of Mental Health, ASL Cagliari, Cagliari, Italy.
Caterina
C
Burrai
Psychiatric Diagnosis and Treatment Service I, Department of Mental Health, ASL Cagliari, Cagliari, Italy.
Antonella
A
Baita
Psychiatric Diagnosis and Treatment Service II, Department of Mental Health, ASL Cagliari, Cagliary, Italy.
Pierfranco
P
Trincas
Psychiatric Diagnosis and Treatment Service II, Department of Mental Health, ASL Cagliari, Cagliary, Italy.
Emanuela
E
Trogu
Psychiatric Diagnosis and Treatment Service I, Department of Mental Health, ASL Cagliari, Cagliari, Italy.
Liliana
L
Campus
Head, Department of Mental Health, ASL Cagliari, Cagliari, Italy.
Augusto
A
Contu
Section of Clinical Psychology, Department of Education, Psychology, and Philosophy, University of Cagliari, Italy; Genneruxi Medical Center, Cagliari, Italy.
Antonio
A
Preti
D000328:Adult; D032882:Comprehension / Q000502:physiology*; D005260:Female; D006212:Hallucinations / Q000503:physiopathology*; D006801:Humans; D007802:Language; D008297:Male; D019365:Metaphor; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000503:physiopathology*; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult
Hallucinations; Metaphor comprehension; Psychosis