Cannabis Increases Spontaneous Mind-Wandering and Impairs the Ability to Control It

What the researchers found

In a three-session ABA design (abstinent-cannabis-abstinent), cannabis use was associated with a large increase in spontaneous mind-wandering during a metronome timing task. When instructed to mind-wander 20% or 80% of the time, cannabis reduced participants' ability to adjust their deliberate mind-wandering and task performance to match instructions, suggesting impaired regulation of attention.

Why it matters

Mind-wandering is linked to creativity but also to accidents, poor learning, and mental health challenges. This study provides direct evidence that cannabis not only increases spontaneous mind-wandering but specifically impairs the ability to control it, which has practical implications for activities requiring sustained attention.

The numbers in context

Three sessions per participant (ABA design). Cannabis produced a 'large' increase in spontaneous mind-wandering. Smaller increase in deliberate mind-wandering. Impaired response to instructions to adjust mind-wandering levels.

How the study worked

Regular cannabis users completed three remote sessions: two on planned abstinence days and one immediately after planned cannabis use. Each session included three blocks of the Metronome Response Task with intermittent self-reports of spontaneous and deliberate mind-wandering. Participants used legally purchased pre-rolls.

What this study cannot tell us

Remote study design relies on self-report. No placebo control (participants knew when they used cannabis). Cannot control for dose, strain, or potency. Naturalistic use means variable exposure. Regular users may not represent occasional users.

How to read the evidence

Moderate: within-subjects design with abstinence controls, but no placebo blinding and self-report measures.

When this study was published

Published in 2025.

The bigger picture

The distinction between spontaneous (uncontrolled) and deliberate (intentional) mind-wandering is important. Cannabis appears to primarily increase the uncontrolled type while impairing the ability to regulate attention, which could explain reported difficulties with focus and task completion during cannabis use.

Questions still open

• Does the mind-wandering effect persist after cannabis wears off?
• Do different cannabis strains or cannabinoids affect mind-wandering differently?
• Could the increased spontaneous mind-wandering be harnessed for creative tasks?

Common questions

Read the original research

The effects of cannabis on mind-wandering.

Heliyon, 11(4), e42911

Citation

Safati, Adrian Berk; Alkheder, Wisam Almohamad; Lowe, Cassandra Justine; Smilek, Daniel. (2025). The effects of cannabis on mind-wandering.. Heliyon, 11(4), e42911. https://doi.org/10.1016/j.heliyon.2025.e42911

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