Cannabis use was not linked to changes in a learning task tied to psychosis, but was linked to higher schizotypy scores
In 307 healthy adults, neither lifetime nor current cannabis use was associated with disrupted Kamin blocking (a learning measure impaired in schizophrenia), though current users scored higher on disorganized schizotypy and aberrant salience.
Quick Facts
What This Study Found
Neither lifetime nor current cannabis use was associated with changes in Kamin blocking scores. However, current cannabis users had higher Disorganised SPQ dimension scores and higher total and sub-scale values on the Aberrant Salience Inventory. A modest positive link between Kamin blocking and disorganized schizotypy was observed.
Key Numbers
307 healthy participants; no significant association between cannabis use and Kamin blocking scores; current users had higher Disorganised SPQ and Aberrant Salience Inventory scores; higher "Senses Sharpening" ASI sub-scale predicted decreased Kamin blocking only in non-users
How They Did This
Cross-sectional online study of 307 healthy participants with no psychiatric history. Kamin blocking was measured using Oades' "mouse in the house task." Schizotypy was assessed with the Schizotypal Personality Questionnaire and aberrant salience with the Aberrant Salience Inventory. Cannabis use history was collected via the modified Cannabis Experience Questionnaire.
Why This Research Matters
The hypothesis that cannabis disrupts salience attribution (a proposed mechanism for psychosis) was not supported by this associative learning measure, even though cannabis users did show elevated self-reported schizotypy and aberrant salience.
The Bigger Picture
The disconnect between self-reported aberrant salience (elevated in cannabis users) and objective salience attribution performance (unchanged) raises questions about whether these measures tap the same construct, and whether the cannabis-psychosis pathway involves mechanisms beyond simple salience disruption.
What This Study Doesn't Tell Us
Cross-sectional design. Online behavioral testing platform may introduce noise. Non-clinical sample limits generalizability to those at clinical psychosis risk. Kamin blocking paradigm has shown inconsistent results across studies.
Questions This Raises
- ?Why do cannabis users report more aberrant salience experiences yet perform normally on an objective salience task?
- ?Does the Kamin blocking paradigm adequately capture the type of salience disruption relevant to cannabis-related psychosis risk?
Trust & Context
- Key Stat:
- No significant association between cannabis use and Kamin blocking performance
- Evidence Grade:
- Adequately powered cross-sectional study with validated measures, but online testing and non-clinical sample limit interpretability.
- Study Age:
- Published in 2021.
- Original Title:
- Cannabis Use, Schizotypy and Kamin Blocking Performance.
- Published In:
- Frontiers in psychiatry, 12, 633476 (2021)
- Authors:
- Dawes, Christopher(3), Bickerdike, Andrea(3), O'Neill, Cian(3), Carneiro Pereira, Sarah, Waddington, John L, Moran, Paula M, O'Tuathaigh, Colm M P
- Database ID:
- RTHC-03089
Evidence Hierarchy
A snapshot of a population at one point in time.
What do these levels mean? →Frequently Asked Questions
What is Kamin blocking?
Kamin blocking is a form of selective associative learning where prior learning about one cue "blocks" learning about a new cue. This blocking effect is disrupted in people with schizophrenia, possibly because they assign excessive importance (salience) to irrelevant stimuli.
Did cannabis affect any measures?
Yes. Current cannabis users scored higher on the Disorganised dimension of the Schizotypal Personality Questionnaire and on the Aberrant Salience Inventory. However, these self-reported differences did not translate to impaired performance on the objective learning task.
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Cite This Study
https://rethinkthc.com/research/RTHC-03089APA
Dawes, Christopher; Bickerdike, Andrea; O'Neill, Cian; Carneiro Pereira, Sarah; Waddington, John L; Moran, Paula M; O'Tuathaigh, Colm M P. (2021). Cannabis Use, Schizotypy and Kamin Blocking Performance.. Frontiers in psychiatry, 12, 633476. https://doi.org/10.3389/fpsyt.2021.633476
MLA
Dawes, Christopher, et al. "Cannabis Use, Schizotypy and Kamin Blocking Performance.." Frontiers in psychiatry, 2021. https://doi.org/10.3389/fpsyt.2021.633476
RethinkTHC
RethinkTHC Research Database. "Cannabis Use, Schizotypy and Kamin Blocking Performance." RTHC-03089. Retrieved from https://rethinkthc.com/research/dawes-2021-cannabis-use-schizotypy-and
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.