To the Editor In JAMA Psychiatry, Rasetti et al1 presented a study of parahippocampal function during a declarative memory task in patients with schizophrenia and their healthy siblings. The authors found that during the encoding of visual scenes, both groups showed relatively reduced parahippocampal activation compared with healthy control individuals. In control participants, the degree of parahippocampal activation during encoding was positively correlated with their visual-memory scores. These findings suggest that parahippocampal hypoactivation during memory encoding may be an intermediate biological phenotype related to psychosis vulnerability.