Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally (...) vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing. (shrink)

Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally (...) vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing. (shrink)

Using the Stroop paradigm, we have previously shown that a specific suggestion can remove or reduce involuntary conflict and alter information processing in highly suggestible individuals . In the present study, we carefully matched less suggestible individuals to HSIs on a number of factors. We hypothesized that suggestion would influence HSIs more than LSIs and reduce the Stroop effect in the former group. As well, we conducted secondary post hoc analyses to examine negative priming – the apparent disruption of the (...) response to a previously-ignored item. Our present findings indicate that suggestion reduces Stroop effects in HSIs. Secondary analyses show that LSIs had an NP effect at baseline and that suggestion influenced the NP condition. Thus, at least in this experimental context, suggestion seems to dampen a deeply-engrained and largely automatic process – reading – by wielding a larger influence on HSIs relative to comparable LSIs. (shrink)

Can suggestion, particularly hypnotic suggestion, influence cognition? Addressing this intriguing question experimentally is on the rise in cognitive research, nowhere more prevalently than in the domain of cognitive control and attention. This may well rest on the intuitive connection between hypnotic suggestion and attention, where the hypnotist controls the subject’s attention. Particularly impressive has been the work of Raz and his colleagues demonstrating the modulation and even the complete elimination of classic Stroop color–word interference when subjects are given a posthypnotic (...) suggestion that words are meaningless. Overriding a highly practiced, possibly even automatic response like reading is testament to the attentional control that can be exerted under hypnotic suggestion. What else do we need to know—in the Stroop context and more broadly—to obtain a clear picture of how suggestion can orchestrate attention? (shrink)

Hypnosis is associated with profound changes in conscious experience and is increasingly used as a cognitive tool to explore neuropsychological processes. Studies of this sort typically employ suggestions following a hypnotic induction to produce changes in perceptual experience and motor control. It is not clear, however, to what extent the induction procedure serves to facilitate suggested phenomena. This study investigated the effect on suggestibility of a hypnotic induction and labelling that procedure ‘hypnosis.’ Suggestibility of participants was tested before and after (...) an adapted hypnotic procedure, which was either labelled as ‘hypnosis’ or as ‘relaxation.’ The hypnotic procedure produced a modest increase in suggestibility when it was called ‘relaxation,’ but a very significant increase if it was labelled ‘hypnosis.’ The results are important for both clinical and experimental applications and indicate that labelling an induction procedure ‘hypnosis’ is an important determinant of subsequent responses to suggestion. (shrink)

Adaptationists explain the evolution of religion from the cooperative effects of religious commitments, but which cooperation problem does religion evolve to solve? I focus on a class of symmetrical coordination problems for which there are two pure Nash equilibriums: (1) ALL COOPERATE, which is efficient but relies on full cooperation; (2) ALL DEFECT, which is inefficient but pays regardless of what others choose. Formal and experimental studies reveal that for such risky coordination problems, only the defection equilibrium is evolutionarily stable. (...) The following makes sense of otherwise puzzling properties of religious cognition and cultures as features of cooperative designs that evolve to stabilise such risky exchange. The model is interesting because it explains lingering puzzles in the data on religion, and better integrates evolutionary theories of religion with recent, well-motivated models of cooperative niche construction. (shrink)

Cognitive scientists distinguish between automatic and controlled mental processes. Automatic processes are either innately involuntary or become automatized through extensive practice. For example, reading words is a purportedly automatic process for proficient readers and the Stroop effect is consequently considered the “gold standard” of automated performance. Although the question of whether it is possible to regain control over an automatic process is mostly unasked, we provide compelling data showing that posthypnotic suggestion reduced and even removed Stroop interference in highly hypnotizable (...) individuals. Drawing on a large sample of highly hypnotizable participants, we examined the effects of suggestion on Stroop performance both with and without a posthypnotic suggestion to perceive the input stream as meaningless symbols. We show that suggestion administered to highly hypnotizable persons significantly reduced Stroop interference and derailed a seemingly automatic process. (shrink)