Overinclusive thought and loosening of associations are not unique to schizophrenia and are produced in Alzheimer's dementia.

Introduction: Bleuler's concept of loosening of associations which he believed epitomised psychotic thinking can manifest as overinclusion (merging of semantic categories) on semantic categorisation tasks. Overinclusion is explained by excessive activation within the semantic memory network to subordinate features with low associative strength. Therefore patients with degradation of subordinate semantic knowledge (e.