Early dissociation of numbers and letters in the human brain

Copyright © 2020 Elsevier Ltd. All rights reserved..

Numbers and letters are culturally created symbols which are learned through repeated training. This experience leads to a functional specialization of the perceptual system of our brain. Recent evidence suggests a neural dissociation between these two symbols. While previous literature has shown that letters elicit a left lateralized neural response, new studies suggest that numbers elicit preferentially a bilateral or right lateralized response. However, the time course of the neural patterns that characterize this dissociation is still underspecified. In the present study, we investigated with magnetoencephalography (MEG) the spatio-temporal dynamics of the neural response generated by numbers, letters and perceptually matched false fonts presented visually. Twenty-five healthy adults were recorded while participants performed a dot detection task. By including two experiments, we were able to study the effects of single characters as well as those of strings of characters. The signal analysis was focused on the event related fields (ERF) of the MEG signal in the sensors and in the source space. The main results of our study showed an early (<200 msec) preferential dissociation between single numbers and single letters on occipito-temporal sensors. When comparing strings of numbers and pseudowords, they differed also over prefrontal regions of the brain. These data offer a new example of acquired category-specific responses in the human brain.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:130

Enthalten in:

Cortex; a journal devoted to the study of the nervous system and behavior - 130(2020) vom: 01. Sept., Seite 192-202

Sprache:

Englisch

Beteiligte Personen:

Aurtenetxe, Sara [VerfasserIn]
Molinaro, Nicola [VerfasserIn]
Davidson, Doug [VerfasserIn]
Carreiras, Manuel [VerfasserIn]

Links:

Volltext

Themen:

Event related fields
Journal Article
Letters
Magnetoencephalography
Numbers
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 21.06.2021

Date Revised 21.06.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.cortex.2020.03.030

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM31255740X