Hypnosis and Cognitive Control (2026)
Anoushiravan Zahedi
Department of Psychology, University of Muenster, Germany
Correspondence: azahedi@uni-muenster.de; anoushiravanzahedi@gmail.com
Keywords: hypnosis, cognitive control, inhibitory control, working memory, cognitive flexibility
Cognitive control refers to the set of mental processes that allow us to regulate our thoughts and actions in pursuit of goals — for instance, ignoring a distraction, updating what we hold in mind, or switching strategies when circumstances change. It underlies attention regulation, inhibitory control, working memory, and cognitive flexibility (Diamond, 2013). A road closure that forces us to reroute is a mundane example: we must suppress the habitual path and plan an alternative. Hypnotic suggestions offer a striking window into how these regulatory processes can be deliberately modulated.
Hypnosis influences cognitive control primarily through task-relevant suggestions — specific instructions that target a particular cognitive process. Most such suggestions are posthypnotic (Iani et al., 2009; Raz et al., 2006): although introduced during hypnosis, they become effective only after its termination, triggered by a predefined cue. Crucially, hypnotic induction alone, without such suggestions, either leaves cognitive performance unchanged (Egner et al., 2005) or diminishes it (Sheehan et al., 1988).
A well-studied example comes from research using the Stroop task (MacLeod, 1991), in which participants must name the ink color of a word while ignoring its meaning — for example, saying “blue” when the word RED is printed in blue ink. This is difficult because reading is the more practiced response, and it must be overridden. A hypnotic suggestion directing attention to a specific spatial location made word reading less viable, and thereby reduced this interference (Sheehan et al., 1988). These findings have been replicated across multiple studies (Raz et al., 2006; Zahedi et al., 2019) and extended to other tasks measuring inhibitory control, such as the Simon task (Iani et al., 2009), and to working memory updating (Lindeløv et al., 2017; Zahedi et al., 2020).
The underlying mechanisms remain debated. Some accounts emphasize changes in automatic, stimulus-driven processing — for instance, a reduced tendency to read words; others point to higher-level, goal-directed processes such as using contextual cues or feedback to guide responses (Egner, 2014). This distinction matters: it speaks to whether hypnotic suggestions alter perception itself or instead change how competing responses are regulated. The fact that suggestions improve working memory updating — a process that relies heavily on goal-directed control — lends support to the latter account.
The implications are both theoretical and practical. These findings show that responsiveness to suggestions is separable from any particular state of consciousness, since suggestions enhance performance even without formal hypnotic induction (Parris & Dienes, 2013). Practically, cognitive control is notoriously difficult to improve through training alone (Diamond, 2013), and deficits in attention regulation, inhibition, and working memory are central to many clinical conditions, including Attention Deficit Hyperactivity Disorder, anxiety, and depression. Some findings suggest that these effects may extend beyond the immediate experimental context (Böhmer & Schmidt, 2022), making task-relevant suggestions a promising complement to existing clinical interventions (Lindeløv et al., 2017). More broadly, hypnosis offers a valuable framework for understanding how suggestion shapes the ways humans adaptively regulate their thoughts and behavior.
References
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