The ‘default mode’ network refers to cortical areas that are active in the absence of goal-directed activity. In previous studies, decreased activity in the ‘default mode’ has always been associated with increased activation in task-relevant areas. We show that the induction of hypnosis can reduce anterior default mode activity during rest without increasing activity in other cortical regions. We assessed brain activation patterns of high and low suggestible people while resting in the fMRI scanner and while engaged in visual tasks, (...) in and out of hypnosis. High suggestible participants in hypnosis showed decreased brain activity in the anterior parts of the default mode circuit. In low suggestible people, hypnotic induction produced no detectable changes in these regions, but instead deactivated areas involved in alertness. The findings indicate that hypnotic induction creates a distinctive and unique pattern of brain activation in highly suggestible subjects. (shrink)

Our sense of self includes awareness of our thoughts and movements, and our control over them. This feeling can be altered or lost in neuropsychiatric disorders as well as in phenomena such as “automatic writing” whereby writing is attributed to an external source. Here, we employed suggestion in highly hypnotically suggestible participants to model various experiences of automatic writing during a sentence completion task. Results showed that the induction of hypnosis, without additional suggestion, was associated with a small but significant (...) reduction of control, ownership, and awareness for writing. Targeted suggestions produced a double dissociation between thought and movement components of writing, for both feelings of control and ownership, and additionally, reduced awareness of writing. Overall, suggestion produced selective alterations in the control, ownership, and awareness of thought and motor components of writing, thus enabling key aspects of automatic writing, observed across different clinical and cultural settings, to be modelled. (shrink)

This study tested the prediction that dissociative tendencies modulate the impact of a hypnotic induction on cognitive control in different subtypes of highly suggestible individuals. Low suggestible , low dissociative highly suggestible , and high dissociative highly suggestible participants completed the Stroop color-naming task in control and hypnosis conditions. The magnitude of conflict adaptation was used as a measure of cognitive control. LS and LDHS participants displayed marginally superior up-regulation of cognitive control following a hypnotic induction, whereas HDHS participants’ performance (...) declined. These findings indicate that dissociative tendencies modulate the influence of a hypnotic induction on cognitive control in high hypnotic suggestibility and suggest that HS individuals are comprised of distinct subtypes with dissimilar cognitive profiles. (shrink)

A hypnotic induction produces different patterns of spontaneous experiences across individuals. The magnitude and characteristics of these responses covary moderately with hypnotic suggestibility, but also differ within levels of hypnotic suggestibility. This study sought to identify discrete phenomenological profiles in response to a hypnotic induction and assess whether experiential variability among highly suggestible individuals matches the phenomenological profiles predicted by dissociative typological models of high hypnotic suggestibility. Phenomenological state scores indexed in reference to a resting epoch during hypnosis were submitted (...) to a latent profile analysis. The profiles in the derived four-class solution differed in multiple experiential dimensions and hypnotic suggestibility. Highly suggestible individuals were distributed across two classes that exhibited response patterns suggesting an inward attention subtype and a dissociative subtype. These results provide support for dissociative typological models of high hypnotic suggestibility and indicate that highly suggestible individuals do not display a uniform response to a hypnotic induction. (shrink)

Following a hypnotic amnesia suggestion, highly hypnotically suggestible subjects may experience amnesia for events. Is there a failure to retrieve the material concerned from autobiographical memory, or is it retrieved but blocked from consciousness? Highly hypnotically suggestible subjects produced free-associates to a list of concrete nouns. They were then given an amnesia suggestion for that episode followed by another free association list, which included 15 critical words that had been previously presented. If episodic retrieval for the first trial had been (...) blocked, the responses on the second trial should still have been at least as fast as for the first trial. With semantic priming, they should be faster. In fact, they were on average half a second slower. This suggests that the material had been retrieved but blocked from consciousness. A goal-oriented information processing framework is outlined to interpret these and related data. (shrink)

The demonstration that hypnotic suggestion can inhibit word/colour Stroop highlights one of the benefits of using hypnosis to explore cognitive psychology and in particular attentional processes. The compelling results using a rigorous design have particular relevance for the presumed automaticity of some forms of information processing. Moreover the results support the potential that hypnotic suggestion offers for creating clinically informed analogues of relevant psychological and neuropsychological conditions. As with all novel research, the results of Raz and Campbell raise further operational (...) and theoretical questions, relating in this case to the use of hypnotic, post-hypnotic and non-hypnotic suggestion and the utility of existing measures of hypnotizability. (shrink)

Despite the compelling subjective experience of executive self-control, we argue that ‘consciousness’ contains no top-down control processes. We propose that ‘consciousness’ involves no executive, causal or controlling relationship with any of the familiar psychological processes conventionally attributed to it. In our view all psychological processing and psychological products are non-conscious. In particular, we argue that all ‘contents of consciousness’ are generated by and within non-conscious brain systems in the form of a continuous self-referential personal narrative that is not directed or (...) influenced in any way by the ‘experience of consciousness’. This continuously updated personal narrative arises from selective ‘internal broadcasting’ of outputs from non-conscious executive systems that have access to all forms of cognitive processing, sensory information and motor control. The personal narrative provides information for storage in autobiographical memory and is underpinned by constructs of self and agency, also created in non-conscious systems. The experience of consciousness, is seen as a passive accompaniment to the non-conscious processes of internal broadcasting and the creation of the personal narrative. In this sense personal awareness is analogous to the rainbow which accompanies physical processes in the atmosphere but exerts no influence over them. Though at an individual level it is an end-product created by non-conscious executive systems, the personal narrative serves the powerful evolutionary function of enabling individuals to communicate (externally broadcast) the contents of internal broadcasting. This in turn allows the recipients to generate potentially adaptive strategies, such as predicting the behavior of others and underlies the development of social and cultural structures, that promote species survival. Consequently, it is the capacity to communicate to others the contents of the personal narrative that confers an evolutionary advantage – not the experience of consciousness (personal awareness) itself. (shrink)

In this paper, I defend Non-Inferentialism about mental states, the view that we can perceive some mental states in a direct, non-inferential way. First, I discuss how the question of mental state perception is to be understood in light of recent debates in the philosophy of perception, and reconstruct Non-Inferentialism in a way that makes the question at hand—whether we can perceive mental states or not—scientifically tractable. Next, I motivate Non-Inferentialism by showing that under the assumption of the widely-accepted Principle (...) of Cognitive Economy, any account that treats mental state perception as an inferential process commits itself to an unrealistically inefficient picture of our cognitive architecture. Drawing on research in cognitive science, I will then show that my Non-Inferentialist view receives direct support by the available empirical evidence. I conclude that there is no psychologically relevant sense in which perception of mental states differs from paradigmatic cases of perception, such as the perception of ordinary objects. (shrink)

This functional Magnetic Resonance Imaging study investigated high and low suggestible people responding to two visual hallucination suggestions with and without a hypnotic induction. Participants in the study were asked to see color while looking at a grey image, and to see shades of grey while looking at a color image. High suggestible participants reported successful alterations in color perception in both tasks, both in and out of hypnosis, and showed a small benefit if hypnosis was induced. Low suggestible people (...) could not perform the tasks successfully with or without the hypnotic induction. The fMRI results supported the self report data, and changes in brain activity were found in a number of visual areas. The results indicate that a hypnotic induction, although having the potential to enhance the ability of high suggestible people, is not necessary for the effective alteration of color perception by suggestion. (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)

Consciousness as used here, refers to the private, subjective experience of being aware of our perceptions, thoughts, feelings, actions, memories including the intimate experience of a unified self with the capacity to generate and control actions and psychological contents. This compelling, intuitive consciousness-centric account has, and continues to shape folk and scientific accounts of psychology and human behavior. Over the last 30 years, research from the cognitive neurosciences has challenged this intuitive social construct account when providing a neurocognitive architecture for (...) a human psychology. Growing evidence suggests that the executive functions typically attributed to the experience of consciousness are carried out competently, backstage and outside subjective awareness by a myriad of fast, efficient non-conscious brain systems. While it remains unclear how and where the experience of consciousness is generated in the brain, we suggested that the traditional intuitive explanation that consciousness is causally efficacious is wrong-headed when providing a cognitive neuroscientific account of human psychology. Notwithstanding the compelling 1st-person experience that convinces us that subjective awareness is the mental curator of our actions and thoughts, we argue that the best framework for building a scientific account is to be consistent with the biophysical causal dependency of prior neural processes. From a 3rd person perspective,, we propose that subjective awareness lacking causal influence, is than our experience of being aware, our awareness of our psychological content, knowing that we are aware, and the belief that that such experiences are evidence of an agentive capacity shared by others. While the human mind can be described as comprising both conscious and nonconscious aspects, both ultimately depend on neural process in the brain. In arguing for the counter-intuitive epiphenomenal perspective, we suggest that a scientific approach considers all mental aspects of mind including consciousness in terms of their underlying, preceding biological changes, in the realization that most brain processes are not accompanied by any discernible change in subjective awareness. (shrink)

Folie à deux is the transference of delusional ideas from one 'primary' individual to one or more 'secondary' individuals (Lasègue & Falret, 1877). However, it is difficult to investigate experimentally because often only one patient is identified as delusional. We investigated whether hypnosis could model the experiences of the secondary in this delusion. Our primary was a confederate, who displayed two delusional beliefs and attempted to transmit them to hypnotised subjects. We manipulated the status of the confederate so that they (...) were portrayed as either "credible" or merely "interesting". Many high hypnotisable individuals adopted the confederate's beliefs and confabulated evidence in support of them. Also, subjects who interacted with a credible confederate extended their delusions beyond those displayed by the confederate. We discuss the strengths and limitations of this approach and suggest ways to improve the validity of this model. (shrink)

Mirrored-self misidentification is the delusional belief that one's own reflection in the mirror is a stranger. In two experiments, we tested the ability of hypnotic suggestion to model this condition. In Experiment 1, we compared two suggestions based on either the delusion's surface features (seeing a stranger in the mirror) or underlying processes (impaired face processing). Fifty-two high hypnotisable participants received one of these suggestions either with hypnosis or without in a wake control. In Experiment 2, we examined the extent (...) to which social cues and role-playing could account for participants' behaviour by comparing the responses of 14 hypnotised participants to the suggestion for impaired face processing (reals) with those of 14 nonhypnotised participants instructed to fake their responses (simulators). Overall, results from both experiments confirm that we can use hypnotic suggestion to produce a compelling analogue of mirrored-self misidentification that cannot simply be attributed to social cues or role-playing. (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)

Clinical delusions are difficult to investigate in the laboratory because they co-occur with other symptoms and with intellectual impairment. Partly for these reasons, researchers have recently begun to use hypnosis with neurologically intact people in order to model clinical delusions. In this paper we describe striking analogies between the behavior of patients with a clinical delusion of mirrored self misidentification, and the behavior of highly hypnotizable subjects who receive a hypnotic suggestion to see a stranger when they look in the (...) mirror. Based on these analogies, we argue that the use of hypnosis is a reliable method to investigate the surface features of clinical delusions. But to what extent can hypnosis successfully recreate delusions? Can it also contribute to a better understanding of delusion formation? Although clinical delusions and hypnotically induced beliefs are different in etiology, some analogies can be identified in the underlying processes that characterise them, based on the two-factor theory of delusion formation. (shrink)

We show how an epistemology informed by cognitive science promises to shed light on an ancient problem in the philosophy of mathematics: the problem of exactness. The problem of exactness arises because geometrical knowledge is thought to concern perfect geometrical forms, whereas the embodiment of such forms in the natural world may be imperfect. There thus arises an apparent mismatch between mathematical concepts and physical reality. We propose that the problem can be solved by emphasizing the ways in which the (...) brain can transform and organize its perceptual intake. It is not necessary for a geometrical form to be perfectly instantiated in order for perception of such a form to be the basis of a geometrical concept. (shrink)