ABSTRACT
Most of the negative symptoms of schizophrenia are behavioural abnormalities and thus should more properly be called signs. I call them behavioural abnormalities because clinicians assess them by observing behaviour. Paradoxically these behavioural signs are more difficult to assess reliably than the subjective, positive symptoms. As a consequence there are many studies concerned with the definition and assessment of negative signs and with studying their natural history (when they develop and how they relate to outcome; see Lewine, 1985). Few studies have attempted to understand the cognitive processes which underlie negative signs (Table 4.1).
