Background. Previous studies on semantic priming have
suggested that schizophrenic patients with
language disturbances demonstrate enhanced semantic and indirect semantic
priming effects relative
to controls. However, the interpretation of semantic priming studies in
schizophrenic patients is
obscured by methological problems and several artefacts (such as length
of illness). We, therefore,
used a psychometric high-risk approach to test whether healthy subjects
reporting language
disturbances resembling those of schizophrenics (as measured by the Frankfurt
Complaint
Questionnaire subscale ‘language’) display increased priming
effects. In addition, the Schizotypal
Personality Questionnaire was used to cover symptoms of schizotypal personality.
Enhanced
priming was expected to occur under conditions favouring automatic processes.
Methods. One hundred and sixty healthy subjects performed a
lexical decision semantic priming
task containing two different stimulus onset asynchronicities (200 ms and
700 ms) with two
experimental conditions (semantic priming and indirect semantic priming)
each.
Results. Analyses of variance revealed that the Frankfurt Complaint
Questionnaire-‘language’ high
scorers significantly differed from low scorers in three of the four priming
conditions indicating
increased automatic spreading activation. No significant results were obtained
for the Schizotypal
Personality Questionnaire total and subscales scores.
Conclusions. In line with Maher and Spitzer it is suggested
that increased automatic spreading
activation underlies schizophrenia-typical language disturbances which
in our study cannot be
attributed to confounding variables such as different reaction time baselines,
medication or length
of illness. Finally, results confirm that the psychometric high-risk approach
is an important tool for
investigating issues relevant to schizophrenia.