Exploring lateralization during memory through hemispheric pre-activation: Differences based on the stimulus type

ABSTRACT

The original approach of the Hemispheric Encoding/Retrieval Asymmetry model (HERA) was aimed at the operations of encoding and retrieving episodic memories. However, whether HERA presumptions can apply to different types of stimuli (e.g., words and pictures) continues to be a matter of debate. Therefore, in order to analyse the effects of brain pre-activation on subsequent memory, HERA was tested through a hand-clenching paradigm using four types of stimuli: words, fractal images, silhouettes of common objects, and pseudowords. Results revealed that only the memory of words and pseudowords was enhanced by hand-clenching pre-activation, according to HERA predictions. Since the cognitive processes underlying recognition of verbal stimuli are considered to follow a cognitive route involving grapheme-morpheme conversion, it could be hypothesized that hand-clenching pre-activation might be associated with a selective pre-activation of the brain circuits participating in that pathway. Hence, the present work broadens possible interpretations behind the effects of hand-clenching on memory, based on the process engaged and the type of stimulus to be remembered.

KEYWORDS:

• Episodic memory
• brain asymmetry
• HERA
• hand-clenching
• pictorial

Acknowledgements

The authors would like to thank Sebastian Idesis, Nicolas Bruno, Iair Embon, and Tomas D’Amelio for their help in data collection and useful comments. We also would like to thank Mrs Veronica Canziani and Dr Miguelangel Verde for their corrections to the English of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by Salvador University [Project code: 1574].