TY - JOUR

T1 - Explicit encoding vs. fast mapping of novel spoken words

T2 - Electrophysiological and behavioural evidence of diverging mechanisms

AU - Shtyrov, Yury

AU - Filippova, Margarita

AU - Perikova, Ekaterina

AU - Kirsanov, Alexander

AU - Shcherbakova, Olga

AU - Blagovechtchenski, Evgeni

N1 - Publisher Copyright: © 2022 The Authors

PY - 2022/7/29

Y1 - 2022/7/29

N2 - It has been claimed that two major neurocognitive mechanisms – instruction-based explicit encoding (EE) and inference-driven fast mapping (FM) may be involved in rapid acquisition of novel words, but their exact neural underpinnings remain poorly understood. To address this, we trained 36 adult participants with 20 novel spoken words in an audio-visual task, carefully balanced between the EE and FM conditions for physical, psycholinguistic and pragmatic properties as well as the overall task setup. To assess the neural dynamics associated with novel word acquisition, we recorded event-related potentials (ERPs) elicited by these words before and after training, and analysed their relationship with the behavioural learning outcomes, measured in a semantic matching task. Both learning regimes led to successful acquisition, which was somewhat more efficient for EE than FM, as indicated by higher accuracy in the behavioural task. We also found that, whereas words learnt via both EE and FM protocols elicited most pronounced ERP peaks at ∼196 and ∼280 ms, these two phases of activity diverged with respect to the learning type. Multiple linear regression and correlation analyses indicated that the learning-induced amplitude dynamics in the earlier peak was significantly related to behavioural performance for FM-learned items, which may possibly be explained by FM's stronger reliance on early automatic mechanisms of word processing. Performance on EE words was, in turn, significantly linked to the amplitude of the second peak only, potentially due to the involvement of later, top-down controlled processes in this type of word acquisition. Grand-average ERP-based source analysis indicated a left-lateralised activity in the anterior-temporal lobe for FM learning, and a bilateral activation for EE. The results confirm the existence of partially diverging neurocognitive systems for word acquisition and suggest that the configuration of newly established word memory circuits depends on the mode of their acquisition.

AB - It has been claimed that two major neurocognitive mechanisms – instruction-based explicit encoding (EE) and inference-driven fast mapping (FM) may be involved in rapid acquisition of novel words, but their exact neural underpinnings remain poorly understood. To address this, we trained 36 adult participants with 20 novel spoken words in an audio-visual task, carefully balanced between the EE and FM conditions for physical, psycholinguistic and pragmatic properties as well as the overall task setup. To assess the neural dynamics associated with novel word acquisition, we recorded event-related potentials (ERPs) elicited by these words before and after training, and analysed their relationship with the behavioural learning outcomes, measured in a semantic matching task. Both learning regimes led to successful acquisition, which was somewhat more efficient for EE than FM, as indicated by higher accuracy in the behavioural task. We also found that, whereas words learnt via both EE and FM protocols elicited most pronounced ERP peaks at ∼196 and ∼280 ms, these two phases of activity diverged with respect to the learning type. Multiple linear regression and correlation analyses indicated that the learning-induced amplitude dynamics in the earlier peak was significantly related to behavioural performance for FM-learned items, which may possibly be explained by FM's stronger reliance on early automatic mechanisms of word processing. Performance on EE words was, in turn, significantly linked to the amplitude of the second peak only, potentially due to the involvement of later, top-down controlled processes in this type of word acquisition. Grand-average ERP-based source analysis indicated a left-lateralised activity in the anterior-temporal lobe for FM learning, and a bilateral activation for EE. The results confirm the existence of partially diverging neurocognitive systems for word acquisition and suggest that the configuration of newly established word memory circuits depends on the mode of their acquisition.

KW - Electroencephalography (EEG)

KW - Event-related potential (ERP)

KW - Explicit encoding (EE)

KW - Fast mapping (FM)

KW - Language acquisition

KW - Word learning

KW - Humans

KW - Electroencephalography

KW - Evoked Potentials/physiology

KW - Temporal Lobe

KW - Semantics

KW - Memory/physiology

KW - Brain Mapping

KW - Adult

KW - Psycholinguistics

UR - http://www.scopus.com/inward/record.url?scp=85131438110&partnerID=8YFLogxK

U2 - 10.1016/j.neuropsychologia.2022.108268

DO - 10.1016/j.neuropsychologia.2022.108268

M3 - Article

C2 - 35569563

AN - SCOPUS:85131438110

VL - 172

JO - Neuropsychologia

JF - Neuropsychologia

SN - 0028-3932

M1 - 108268

ER -