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Highlights • Hypnotic and non-hypnotic suggestions reduce space-valence congruency effects in HHIs. • Both suggestions reduce P2 effects indicating suggestion modulates early attention. • Hypotic suggestion does not affect LPC for positive targets in HHI. • Down arrows evoked larger LPC than up ones with non-hypnotic suggestion in HHIs. Abstract Previous studies have shown that the speed of identifying emotional words is affected by pre-cues of up or down arrows, called the space-valence congruency effect (Zhang, Hu, Zhang, & Wang, 2015). In the present study, we investigate whether this effect is influenced by hypnotic or non-hypnotic suggestions to ignore pre-cues in highly hypnotizable individuals (HHIs). In all conditions, target words (including positive words, negative words and neutral words) primed by up or down arrows were presented to pre-screened HHIs. They were asked to identify whether the target words had emotional valence. Behavioral results showed that the space-valence congruency effect was absent in the hypnotic and non-hypnotic suggestion groups, but present in the non-suggestion control group. Consistently, the amplitudes of P2 components elicited by negative words were significantly larger when primed by down than by up arrows in the non-suggestion control group, and this P2 effect was absent in the hypnotic and non-hypnotic suggestion groups. Moreover, the amplitudes of the late positive components (LPC) showed no significant arrow-priming difference for positive targets in the hypnotic-suggestion and control groups. However, in the non-hypnotic suggestion group, the amplitudes of LPC were significantly larger when primed by down than up arrows for positive targets. Our results showed that suggestions, even without a hypnotic induction, can de-automatize embodied emotional recognition processes and modulate early attentional processing. [ABSTRACT FROM AUTHOR]

Previous studies have consistently demonstrated that superior mnemonists (SMs) outperform normal individuals in domain-specific memory tasks. However, the neural correlates of memory-related processes remain unclear. In the current EEG study, SMs and control participants performed a digit memory task during which their brain activity was recorded. Chinese SMs used a digit-image mnemonic for encoding digits, in which they associated 2-digit groups with images immediately after the presentation of each even-position digit in sequences. Behaviorally, SMs' memory of digit sequences was better than the controls'. During encoding in the study phase, SMs showed an increased right central P2 (150-250ms post onset) and a larger right posterior high-alpha (10-14Hz, 500-1720ms) oscillation on digits at even-positions compared with digits at odd-positions. Both P2 and high-alpha oscillations in the study phase co-varied with performance in the recall phase, but only in SMs, indicating that neural dynamics during encoding could predict successful retrieval of digit memory in SMs. Our findings suggest that representation of a digit sequence in SMs using mnemonics may recruit both the early-stage attention allocation process and the sustained information preservation process. This study provides evidence for the role of dynamic and efficient neural encoding processes in mnemonists. [ABSTRACT FROM AUTHOR]