Table 2.

Comparison of the brain-imaging markers of psychotic and serotonergic hallucinations

	Schizophrenia Spectrum	5-HT2A Agonists	Comparison
Major networks a)During rest b)During task	a) DMN hypoactivation Decreased connectivity within and (mostly) between RSN b) Lack of DMN suppression during tasks—decreased DMN and CEN anticorrelation	a) DMN hypoactivation Decreased connectivity within—increased connectivity between RSN Decreased DMN and CEN anticorrelation b) Not enough evidence	a) Partially similar Differences in changes in connectivity between RSN
Hallucinations a) Symptom capture b) Resting-state analysis	a) Activation of hippocampus and modality-specific secondary cortex with deactivation of DMN and activation of SN and CEN b) Thalamic connectivity with prefrontal cortex lowered—thalamic connectivity with somatosensory cortex increased	a) Not available b) Increased activity in primary visual areas—decreased activity in associative areas Preserved thalamic connectivity with DMN—increased thalamic connectivity with CEN	a) Directly incomparable—mostly primary cortices in psychedelics—mostly associative cortices in SCZs
Link with experience	AH altered resting-state connectivity in left temporal areas VH increased RS connectivity between visual cortex and amygdala in SCZs (AH and VH)	VH / imagery expanded connectivity and activity of V1—VH/imagery correlated with CEN activation

RSNs, resting-state networks; DMN, default mode network; CEN, central-executive network; SN, salience network.