A hallmark of schizophrenia is impaired proverb interpretation, which
could be due to: (1) aberrant activation of disorganized semantic
associations, or (2) working memory (WM) deficits. We assessed 18
schizophrenia patients and 18 normal control participants on proverb
interpretation, and evaluated these two hypotheses by examining within
patients the correlations of proverb interpretation with disorganized
symptoms and auditory WM, respectively. Secondarily, we also explored the
relationships between proverb interpretation and a spectrum of cognitive
functions including auditory sensory-memory encoding (as indexed by the
mismatch negativity (MMN) event-related brain potential (ERP)); executive
function; and social/occupational function. As expected, schizophrenia
patients produced less accurate and less abstract descriptions of proverbs
than did controls. These proverb interpretation difficulties in patients
were not significantly correlated with disorganization or other symptom
factors, but were significantly correlated (p < .05) with WM
impairment, as well as with impairments in sensory-memory encoding,
executive function, and social/occupational function. These results
offer no support for disorganized associations in abnormal proverb
interpretation in schizophrenia, but implicate WM deficits, perhaps as a
part of a syndrome related to generalized frontal cortical dysfunction.
(JINS, 2007, 13, 653–663.)