Hypnosis appears to generate unusual—and sometimes even astonishing—changes in the contents of consciousness. Hypnotic subjects report perceiving things that are not there, they report not perceiving things that are there, and they report unusual alterations in the phenomenology of agency. In addition to apparent alterations in the contents of consciousness, hypnosis also appears to involve alterations in the structure of consciousness. According to many theorists—most notably Hilgard—hypnosis demonstrates that the unity of consciousness is an illusion (Hilgard 1977).
Cognitive functions associated with the frontal lobes of the brain may be specifi cally involved in hypnosis. Thus, the frontal area of the brain has recently been of great interest when searching for neural changes associated with hypnosis. We tested the hypothesis that EEG during pure hypnosis would differ from the normal non-hypnotic EEG especially above the frontal area of the brain. The composition of brain oscillations was examined in a broad frequency band (130 Hz) in the electroencephalogram (EEG) of (...) a single virtuoso subject. Data was collected in two independent data collection periods separated by one year. The hypnotic and non-hypnotic conditions were repeated multiple times during each data acquisition session. We found that pure hypnosis induced reorganization in the composition of brain oscillations especially in prefrontal and right occipital EEG channels. Additionally, hypnosis was characterized by consistent rightside-dominance asymmetry. In the prefrontal EEG channels the composition of brain oscillations included spectral patterns during hypnosis that were completely different from those observed during non-hypnosis. Furthermore, the EEG spectral patterns observed overall during the hypnotic condition did not return to the pre-hypnotic baseline EEG immediately when hypnosis was terminated. This suggests that for the brain, the return to a normal neurophysiological baseline condition after hypnosis is a time-consuming process. The present results suggest that pure hypnosis is characterized by an increase in alertness and heightened attention, refl ected as cognitive and neuronal activation. Taken together, the present data provide support for the hypothesis that in a very highly hypnotizable person (a hypnotic virtuoso) hypnosis as such may be accompanied by a changed pattern of neural activity in the brain. (shrink)
The phenomenon of hypnosis provides a rich paradigm for those seeking to understand the processes that underlie consciousness. Understanding hypnosis tells us about a basic human capacity for altered experiences that is often overlooked in contemporary western societies. Throughout the 200 year history of psychology, hypnosis has been a major topic of investigation by some of the leading experimenters and theorists of each generation. Today hypnosis is emerging again as a lively area of research within cognitive (systems level) neuroscience informing (...) basic questions about the structure and biological basis of conscious states. This book describes the latest advances in understanding hypnosis and similar trance states by researchers within the neuroscience of consciousness. It contains many new and exciting contributions from up and coming researchers and provides a lively debate on methodological and theoretical issues central to the development of emerging research paradigms in the neuroscience of conscious states. The book introduces and describes many of the recent new tools that have become available to researchers in this field. Academics, researchers, and clinicians wanting to develop their knowledge of the latest findings, theories and methods in the scientific study of hypnosis and related states of consciousness will find this an up to date guide to this rapidly advancing field. (shrink)
Cortex functional connectivity associated with hypnosis was investigated in a single highly hypnotizable subject in a normal baseline condition and under neutral hypnosis during two sessions separated by a year. After the hypnotic induction, but without further suggestions as compared to the baseline condition, all studied parameters of local and remote functional connectivity were significantly changed. The significant differences between hypnosis and the baseline condition were observable (to different extent) in five studied independent frequency bands (delta, theta, alpha, beta, and (...) gamma). The results were consistent and stable after 1 year. Based on these findings we conclude that alteration in functional connectivity of the brain may be regarded as a neuronal correlate of hypnosis (at least in very highly hypnotizable subjects) in which separate cognitive modules and subsystems may be temporarily incapable of communicating with each other normally. (shrink)
The last few years have seen the publication of a number of studies by researchers claiming to have induced “synaesthesia”, “pseudo-synaesthesia”, or “synaesthesia-like” phenomena in non-synaesthetic participants. Although the intention of these studies has been to try and shed light on the way in which synaesthesia might have been acquired in developmental synaesthestes, we argue that they may only have documented a phenomenon that has elsewhere been accounted for in terms of the acquisition of sensory associations and is not evidently (...) linked to synaesthesia. As synaesthesia remains largely defined in terms of the involuntary elicitation of conscious concurrents, we suggest that the theoretical rapprochement with synaesthesia (in any of its guises) is unnecessary, and potentially distracting. It might therefore be less confusing if researchers were to avoid referring to synaesthesia when characterizing cases that lack robust evidence of a conscious manifestation. Even in the case of those other conditions for which conscious experiences are better evidenced, when training has been occurred during hypnotic suggestion, or when it has been combined with drugs, we argue that not every conscious manifestation should necessarily be counted as synaesthetic. Finally, we stress that cases of associative learning are unlikely to shed light on two highly specific characteristic of developmental synaesthesia in terms of learning patterns: First, their resistance to change through exposure ; Second, the transfer of conditioned responses between concurrents and inducers after training. We conclude by questioning whether, in adulthood, it is ever possible to acquire the kind of synaesthesia that is typically documented in the developmental form of the condition. The available evidence instead seems to point to there being a critical period for the acquisition of synaesthesia, probably only in those with a genetic disposition to develop the condition. (shrink)
Although we are sympathetic to his central thesis about the illusion of will, having previously advanced a similar proposal, Wegner's account of hypnosis is flawed. Hypnotic behavior derives from specific suggestions that are given, rather than from the induction, of trance, and it can be observed in 90% of the population. Thus, it is very pertinent to the illusion of will. However, Wegner exaggerates the loss of subjective will in hypnosis.