Biomedical subjects

Laura Sebastiani

Publications and source records attributed to Laura Sebastiani.

7 recordsLinked to original sources

PubMed2006

Role of relaxation and specific suggestions in hypnotic emotional numbing.

The cognitive characteristics of highly hypnotizable subjects (Highs) allow them to easily modify their cognitive and autonomic state. Under hypnosis, Highs receiving cognitive, fear-like stimulation exhibit the cardiovascular changes typical of fear/stress, but also show an EEG pattern indicating a balance between fear-induced arousal and hypnotic relaxation. Indeed, hypnosis is effective in the attenuation of both emotional experience and behaviour (emotional numbing). The aim of the present experiment was to investigate the possible different role of relaxation and suggestion in hypnotic emotional numbing. Tonic skin conductance, respirogram, heart rate, systolic and diastolic blood pressure were recorded in 3 groups of hypnotized subjects: Group 1 received a fearful guided imagery associated with threat suggestions (Threat) followed by the same fearful suggestion associated with numbing instructions (relaxation and "No-Threat"); Group 2 received the same instructions in the opposite order of presentation; Group 3 received the fearful suggestion with threat instructions twice. The numbing suggestion reduced fear-related emotional experience and autonomic responses; if No-Threat preceded Threat, the heart rate, heart rate variability and blood pressure were also reduced during Threat, in spite of self reports of high negative emotion. Thus, 1) the subjective experience and the autonomic response to fear can be dissociated; 2) the efficacy of numbing suggestion is extended to a subsequent Threat stimulation; 3) habituation does not contribute to the numbing effect. The results indicate that the specific numbing suggestion is the main factor in hypnotic modulation of the experience of fear.

Adult↗

PubMed2006

Suggestions of altered balance: Possible equivalence of imagery and perception.

Hypnotic suggestions describing an altered perception induce congruent changes in the subject's experience and behavior. However, it is not known whether an implicit suggestion, only indirectly referring to an altered perception, induces a behavioral response corresponding to that of the real situation. In this study, an implicit suggestion of backward falling (IMP) was given to high hypnotizable participants not exposed (W-Highs) and exposed (H-Highs) to a hypnotic induction and a group of low hypnotizable individuals (W-Lows). Their posture was evaluated through an elite system. The results after the IMP were compared with those after an explicit suggestion of backward falling (EXP). In both W-Highs and H-Highs, the IMP elicited the backward body sway expected in the corresponding real situation, whereas no response was found in W-Lows. The results are discussed in terms of a possible equivalence of imagery and perception or of a lack of the motor inhibition normally associated with motor imagery.

Adolescent↗

PubMed2005

Hypnotic trait and specific phobia: EEG and autonomic output during phobic stimulation.

In a previous study we showed that healthy highly hypnotizable subjects, during the suggestion of a moderately unpleasant situation administered in awake conditions, exhibited a sympathetic response greatly attenuated with respect to non-hypnotizable individuals. This was interpreted as a natural protection of hypnotizable subjects against the cardiovascular effects of cognitive stress. Aim of the present study was to investigate whether the hypnotic trait is able to modulate the autonomic and cerebral activities also in specific phobic awake hypnotizable (Highs) and non-hypnotizable (Lows) subjects. Electroencephalogram, electrooculogram, electromiogram of corrugator muscle, electrocardiogram, respirogram and tonic electrodermal activity were recorded during a guided mental imagery of an animal phobic object. Phobic stimulation induced in both groups the rise of heart and respiratory frequency and the lowering of skin resistance. These changes are less pronounced in Highs than in Lows and are sustained by a different modulation of the sympatho-vagal balance. During phobic stimulation both groups exhibited a similar significant increase of EEG gamma relative power. At variance, significant stimulation-related decrements of alpha1, theta1 and theta2 activities were found only in Highs that exhibited similar changes during the control and phobic stimulation. Results suggest that hypnotizability is able to modulate cerebral and autonomic responses also in specific phobic subjects. However, the presence of a specific phobia attenuates the effectiveness of hypnotizability as a protective factor against possible stress-related cardiac illness.

Adolescent↗

PubMed2005

Hypnotic modulation of flow-mediated endothelial response to mental stress.

Post-ischaemic flow mediated dilation of peripheral arteries (FMD) is transiently reduced during mental stress. This experiment was aimed at assessing whether hypnosis, which is a powerful relaxation technique, modulated the FMD response to mental stress in subjects with different hypnotic susceptibility. Results showed that hypnotic relaxation prevented the expected stress-related reduction of FMD only in highly hypnotizable subjects, suggesting a protective role of hypnotisability against vascular damage.

Adult↗

PubMed2004

Does hypnotizability modulate the stress-related endothelial dysfunction?

Previous studies suggest that hypnotizability represents a protective factor against the cardiac effects of cognitive stress and that hypnosis prevents vascular stress-induced modifications in highly hypnotizable individuals. The aim of the experiment was to investigate whether a similar effect at vascular level is present in awake subjects with a high (Highs) and a low (Lows) hypnotic susceptibility. Thus, brachial artery post-ischaemic flow-mediated vascular dilation (FMD) was evaluated non-invasively by ultrasound methodology during cognitive stress (mental computation) in Highs and Lows. Results showed that Highs, similarly to that previously observed in hypnotized Highs and in contrast with Lows, did not exhibit any stress-related endothelial dysfunction (FMD decrement). Thus, hypnotizability should be considered a protective factor against vascular disease.

Adult↗

PubMed2004

Traditional acupuncture does not modulate the endothelial dysfunction induced by mental stress.

Acupuncture is a useful tool to treat many diseases, including cardiovascular disorders, but its modulation of stress-related responses is still debated. Aim of this study was to estimate whether the traditional Chinese acupuncture affected the transient impairment of the brachial artery flow-mediated dilation (FMD) produced by acute mental stress. In addition, since a high susceptibility to hypnosis attenuates the endothelial dysfunction elicited by mental calculation, the possible interaction between acupuncture and hypnotizability was investigated. Five low-to-medium and five medium-to-high hypnotizable healthy subjects joined two experimental sessions, for real and sham acupuncture. FMD and heart rate were measured in three conditions: baseline (PRE), after the real or sham acupuncture (ACU) and after mental calculation (MS). Needles were inserted into specific acupoints for real acupuncture and into non-acupoints, corresponding to the same spinal segment, for sham acupuncture. Results showed that the stress-related endothelial dysfunction was not modulated by acupuncture, but influenced by hypnotizability. In fact, highly hypnotizable subjects did not present any dysfunction, at variance with non-susceptible individuals that exhibited the expected stress-related FMD reduction (Mean +/- SD; PRE, 12.10 +/- 2.59; ACU, 10.73 +/- 3.45; MS, 6.48 +/- 1.72). Thus, hypnotizability appears more effective than acupuncture in contrasting the stress effects on the endothelial function. In conclusion, our study indicates the importance of patients' psychological evaluation in order to choose proper relaxation techniques and to evaluate therapeutic results and the necessity to integrate the alternative medicine practice with scientific research.

Acupuncture Therapy↗

PubMed2002

Medial prefrontal cortex early lesion effects on classical conditioned bradycardia.

The effects of medial prefrontal cortex early lesion (mPFl) on classical conditioned bradycardia (CB) were studied in adult rabbits. In lesioned rabbits, baseline HR, orienting and conditioned HR responses were similar to controls. Since mPFl alone does not affect CB, while it is known to prevent the HR increments produced by a concomitant early cerebellar vermal ablation, medial prefrontal cortex must be involved in the reorganization of the CB control mechanisms following early cerebellar vermal ablation.

Animals↗