Table 2.

Basic differences between ASD and SCZ patients for the detection of delusions, hallucinations, and negative symptoms.

Delusions	Not fully evaluable in non-verbal ASD patients
	Clinicians should distinguish between “childish fantasies” and clinical delusional beliefs in ASD patients
	In ASD patients, delusional ideas have a precise and recognizable time of onset along the clinical course of pre-existing childhood-onset neurodevelopmental disorder
Hallucinations	ASD patients show more frequently anomalous perceptual experiences (APEs) than true psychotic hallucinations
	First-hand descriptions of APEs are usually made only by adult high-functioning ASD patients
	APEs should be considered as psychotic hallucinations only if their source is attributed to the outside world.
Negative symptoms	Unlike autistic symptoms, negative symptoms occur after the psychotic onset and have a progressive worsening clinical course
	ASD subjects show “poverty and inappropriateness of reciprocity” rather than affective flattening
	Compared to SCZ patients, in ASD loss of social contact Is frequently associated with repetitive behaviors