Abstract

Abstract
The Relationship between Hypnotisability, Working Memory, and the Process of Automatization

Mahmoud Khodaverdi-Khani
Concordia University, 2017

The literature on hypnosis indicates that high hypnotizable (HH) people tend to follow suggestions more attentively and be less distracted by peripheral information than low hypnotizable (LH) people. Neuro-psychological measures of attention, however, seem to indicate that HHs may demonstrate less efficient executive functions. To compensate this limitation, HHs may have learned to allocate all of their attention to the task at hand and learned to automatize some aspect of information processing. In experiment one, the relationship between working memory and the degree to which participants react to hypnotic suggestions was investigated. Thirty-eight participants who underwent the Harvard Group Scale of Hypnotisability Form A (HGSHS: A) in small group sessions were assessed on a forward and backward digit span, and a reading span tests. The results showed that hypnotisability correlated negatively with the digit span backward and the digit span total tests. In experiment 1b, ten HH and ten LH participants underwent the same procedure as in experiment one with the exception that the reading span was replaced by the N-back test. The results of this experiment replicated the magnitude, direction, and significance of the relationship between hypnotisability and measures of working memory (WM). The analysis of N-back data further revealed a distinction between storage and processing involved in WM, pointing to a dynamic interaction with the automatization of attentional processes. To further investigate the role of WM in the process of automatization, in experiment two, participants’ WM was loaded with zero, three, or five digits while they were performing a visual search task over five sessions. It was hypothesized that if the process of automatization is due to the limited resources available to participants then participants in the high load condition would reach automaticity over the 5 sessions regardless of their hypnotisability level. In addition, it was expected that the HH group would reach automaticity in fewer sessions than the LH or the MH groups regardless of the load condition they were in. Support for the two hypotheses was obtained when the coefficients of variability were analyzed. Across sessions, HHs significantly decreased their coefficients of variability, indicating that more than a simple improvement in speed of processing was at play in their responses. Experiment 2b, following the same methodology, replicated the key findings of experiment 2. These results are discussed in the context of two-process theory and their applicability to the study of hypnotisability and automatization. The current results suggest that individual differences in hypnotisability may be in part linked to variations in WM resources and a more efficient automatization process of information.