RESUMEN
Active engagement improves learning and memory, and self- versus externally generated stimuli are processed differently: perceptual intensity and neural responses are attenuated. Whether the attenuation is linked to memory formation remains unclear. This study investigates whether active oculomotor control over auditory stimuli-controlling for movement and stimulus predictability-benefits associative learning, and studies the underlying neural mechanisms. Using EEG and eye tracking we explored the impact of control during learning on the processing and memory recall of arbitrary oculomotor-auditory associations. Participants (N = 23) learned associations through active exploration or passive observation, using a gaze-controlled interface to generate sounds. Our results show faster learning progress in the active condition. ERPs time-locked to the onset of sound stimuli showed that learning progress was linked to an attenuation of the P3a component. The detection of matching movement-sound pairs triggered a target-matching P3b. There was no general modulation of ERPs through active learning. However, we found continuous variation in the strength of the memory benefit across participants: some benefited more strongly from active control during learning than others. This was paralleled in the strength of the N1 attenuation effect for self-generated stimuli, which was correlated with memory gain in active learning. Our results show that control helps learning and memory and modulates sensory responses. Individual differences during sensory processing predict the strength of the memory benefit. Taken together, these results help to disentangle the effects of agency, unspecific motor-based neuromodulation, and predictability on ERP components and establish a link between self-generation effects and active learning memory gain.
Asunto(s)
Potenciales Evocados , Memoria , Humanos , Potenciales Evocados/fisiología , Estimulación Acústica/métodos , Sonido , Sensación , Percepción Auditiva/fisiología , Electroencefalografía , Potenciales Evocados Auditivos/fisiologíaRESUMEN
When repeatedly exposed to simultaneously presented stimuli, associations between these stimuli are nearly always established, both within as well as between sensory modalities. Such associations guide our subsequent actions and may also play a role in multisensory selection. Thus, crossmodal associations (i.e., associations between stimuli from different modalities) learned in a multisensory interference task might affect subsequent information processing. The aim of this study was to investigate the processing level of multisensory stimuli in multisensory selection by means of crossmodal aftereffects. Either feature or response associations were induced in a multisensory flanker task while the amount of interference in a subsequent crossmodal flanker task was measured. The results of Experiment 1 revealed the existence of crossmodal interference after multisensory selection. Experiments 2 and 3 then went on to demonstrate the dependence of this effect on the perceptual associations between features themselves, rather than on the associations between feature and response. Establishing response associations did not lead to a subsequent crossmodal interference effect (Experiment 2), while stimulus feature associations without response associations (obtained by changing the response effectors) did (Experiment 3). Taken together, this pattern of results suggests that associations in multisensory selection, and the interference of (crossmodal) distractors, predominantly work at the perceptual, rather than at the response, level.