Tolerance to some acute effects of delta-9-tetrahydrocannabinol (THC) develops in a domain-specific way, with more frequent cannabis use linked to reduced intensity of subjective effects like feeling stoned and reduced psychosis-like effects. Tolerance to alertness reduction occurred more readily than tolerance to psychotomimetic effects, while tolerance to memory impairment was weak. Trait schizotypy did not moderate the acute psychosis-like effects of THC. These findings come from a mega-analysis of 128 cannabis users across four double-blind, placebo-controlled studies.
Voice-hearers typically report about four distinct voices, most perceived as male and with negative content. Child-aged voices are significantly less negative than other voices except those perceived as elderly. Variability in voice characteristics is greater between different voices within an individual than between different utterances of the same voice. These findings are inconsistent with cognitive models that attribute voices to misattributed inner speech and better support a dissociation model of voice-hearing. The results suggest that classifying voices by subtype or dimensional methods may be useful, and that clinical assessment should more systematically evaluate the multiplicity of voices.