Hypnotizability-related effects of vestibular impairment on posture and locomotion

Neuropsychological considerations for long-duration deep spaceflight

The deep space environment far beyond low-Earth orbit (LEO) introduces multiple and simultaneous risks for the functioning and health of the central nervous system (CNS), which may impair astronauts' performance and wellbeing. As future deep space missions to Mars, moons, or asteroids will also exceed current LEO stay durations and are estimated to require up to 3 years, we review recent evidence with contemporary and historic spaceflight case studies addressing implications for long-duration missions. To highlight the need for specific further investigations, we provide neuropsychological considerations integrating cognitive and motor functions, neuroimaging, neurological biomarkers, behavior changes, and mood and affect to construct a multifactorial profile to explain performance variability, subjective experience, and potential risks. We discuss the importance of adopting a neuropsychological approach to long-duration deep spaceflight (LDDS) missions and draw specific recommendations for future research in space neuropsychology.

German Norms of the Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A) and Proposal of a 5-Item Short-Version (HGSHS-5:G)

The Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A), is commonly used to test hypnotizability. There is still some controversy about what exactly hypnotizability is and whether and how it can be measured, especially by the HGSHS:A. Furthermore, a wider clinical use is limited, requiring a testing time of more than 1 hour. We analyzed the German HGSHS:A version for its factorial structure, item contribution, and item difficulty based on test data from six studies, including 1276 persons, to propose a shorter version of the HGSHS:A. We hereby present a 5-item version of the HGSHS:A (HGSHS-5:G), consisting of the challenge items, that was compared with an 11-item version (highly variable posthypnotic amnesia omitted). Age- and gender-specific norms was generated. The HGSHS-5: G showed high validity, reliability, and classification agreement. It reduces test time to 30 minutes thus facilitating wider use of hypnotizability testing.

Asymmetric Tactile Foot Stimulation: How Postural Studies May Suggest New Views of Hypnotizability

Earlier studies have shown hypnotizability-related postural effects of visual suppression and of leg and neck proprioceptive alteration. This study completes this investigation by demonstrating the postural effects of asymmetric tactile foot stimulation in standing participants with different hypnotizability scores. During this stimulation, body sway changed in medium-to-high more than in low-to-medium hypnotizable participants. Findings support the view that high hypnotizability is associated with higher vulnerability of posture to sensory alteration; together with earlier results, they suggest a role of the cerebellum in the observed hypnotizability-related differences and prompt investigation of cerebral structures and factors potentially responsible for both the cognitive and physiological aspects of hypnotizability.

Hypnotizability-dependent accuracy in the reproduction of haptically explored paths

The study assessed differences between highly (Highs) and low hypnotizable (Lows) subjects in the blindfolded reproduction of paths connected at acute or obtuse angles. Reproduction attempts were made after path exploration performed by one finger, with or without concomitant cognitive activities (mental computation or imagery of exploring an angle larger than the explored one). The variables analyzed were: subjective experience (scores of the exploring effort, reproduction difficulty, perceived accuracy of reproduction, attention to mental computation and efficacy of imagery), exploration time, relative error in reproduction (under or overestimation) and the percentage of "successful" trials (absolute error <10°). The results showed that the subjective experience of exploration/reproduction and the exploration times are similar in Highs and Lows and that all subjects underestimate the explored angles and reproduce the acute angle more accurately than the obtuse one. Exploration of the acute angle concomitant with imagery of a larger one reduced its underestimation in both groups. Highs exhibited a larger number of successful trials after exploration of the obtuse angle, while Lows (males) decreased their relative error in the reproduction of the acute angle. In conclusion, in the more demanding condition of reproducing an obtuse angle, the Highs' reproduction was more accurate and more independent of cognitive load than that of the Lows.

Hypnosis in the laboratory creates a window on psychopathology

The authors describe 3 studies in which hypnosis itself is not studied but instead used to create anomalous states in the laboratory that can be studied under controlled conditions. The 1st article is a comprehensive review of programmatic research using hypnosis to elicit and study clinically relevant delusions. The 2nd article reviews studies comparing the brain activity of hysterical/dissociative patients with nonpatients hypnotized and given suggestions for sensory-motor and cognitive anomalies typical of the clinical syndromes. The authors conclude that the hypnosis analogues are relevant and revealing. The 3rd article describes a single experiment using hypnosis to elicit distressing and intrusive memories, typical of acute anxiety disorders. Findings with hypnotic subjects are in keeping with those from patients suffering intrusive memories. Across all 3 papers, hypnosis is shown to be a viable and helpful tool for experimental psychopathology.

Visual identification of haptically explored objects in high and low hypnotizable subjects

Hypnotizability is associated with peculiar characteristics of sensorimotor integration, imaginal abilities, and preferences in the sensory modality of imagery. The visual recognition of haptically explored objects involves an interaction among these processes and is a proper tool to investigate their possible hypnotizability-related modulation. Sixteen high hypnotizables and 16 lows participated in the study. Higher frequencies of correct recognition (RF) were observed in highs. RF improved across both groups. As an effect of learning, shorter recognition times were found in males among highs and in females among lows. The findings are consistent with the literature suggesting that hypnotizability levels may be associated with specific modes of sensory integration and/or imagery.