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• We investigated whether paranoid and misidentification subtypes of psychosis in Alzheimer's disease represent distinct subphenotypes. • Greater global cognitive deficits and an accelerated rate of global cognitive decline were observed in the misidentification subtype. • The misidentification subtype was associated with greater volume loss in multiple regions, including the ventral visual pathway. • Poorer performance on tests of object recognition and sustained visual attention was observed in the misidentification subtype. • Combined, these findings suggest there is greater dysfunction in networks involved in visuoperceptual processing in the misidentification subtype. This study aimed to review the neurobiological and neuropsychological correlates of paranoid (persecutory delusions) and misidentification (misidentification delusions and/or hallucinations) subtypes of psychosis in dementia, to establish if they represent distinct subphenotypes. Nine studies were eligible, all included patients with Alzheimer's disease. Greater global cognitive deficits and an accelerated global cognitive decline were observed in the misidentification subtype. Neuroimaging studies showed more marked volume loss in multiple regions in patients with the misidentification subtype, including those involved in object recognition and the processing of information on spatial and temporal context. A single study found greater impairment in visual sustained attention and object recognition in the misidentification subtype. The small number of studies and methodological heterogeneity limit interpretation of the findings. Nevertheless, these findings would tentatively suggest that there may be additional or accelerated pathological change in functional networks involved in visuoperceptual processing in the misidentification subtype. This should be further explored in prospective studies and the investigation extended to other forms of dementia, to gain a transdiagnostic perspective. [ABSTRACT FROM AUTHOR]