Age- and gender-related differences in verbal semantic processing: the development of normative electrophysiological data in the Flemish population

ABSTRACT

Categorical and associative relationships among words are two key forms of semantic knowledge. In this study, we examined ageing and gender effects on the processing of both types of semantic relationships by using the event-related potential technique. Moreover, we aimed to develop normative electrophysiological data for clinical purposes. One hundred and ten healthy subjects were divided among three age groups and subjected to two auditory word priming paradigms. Early auditory processing was influenced by increasing age as shown by larger P1 amplitudes and by delayed onsets of the N1 and P2. Conversely, ageing effects on the main N400 effect were limited to an increased right hemispheric lateralisation pattern for associative relationships. Gender effects could be demonstrated, with women showing larger P2 amplitudes and larger semantic priming effects in comparison to men. The interpretation of these findings is discussed and the practical utility of the obtained normative data is emphasised.

KEYWORDS:

• Ageing
• gender
• semantics
• event-related potentials
• normative data

Acknowledgements

We would like to express our gratitude to Professor Peter Hagoort (Radboud University, Nijmegen, The Netherlands) who gave permission to use and adapt his ERP paradigms.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 Thematic relations refer to concepts that perform complementary roles in an event and are often spatial (lawyer – court), temporal (summer – holiday), causal (to fall – pain), functional (bucket – to clean), possessive (butcher – knife) or productive (cow – milk) in nature (Estes et al., 2011; Lin & Murphy, 2001; Mirman et al., 2017).

2 In the visual modality, Grieder et al. (2012) found intact N400 effects during a word priming task with a short SOA. Diminished N400 effects have been revealed in case of long SOAs (Bornkessel-Schlesewsky et al., 2015; Cameli, 1999; Federmeier et al., 2010; Gunter et al., 1998; Iragui et al., 1996; Kutas & Iragui, 1998; Miyamoto et al., 1998).

3 In total, one hundred and twenty-five volunteers participated. Throughout the participant recruitment period, 15 individuals were excluded for the following reasons: technical issues (n=2), MoCA score < 26 (n=2), pronounced hearing loss (n=2), headache (n=1), tiredness (n=3), drop-out (n=1) and ambidexterity (n=4).

4 In the original study of Hagoort et al. (1996), twenty subjects had to write down the first three words that came to their mind for every prime word. One or more occurrences of the target word among their responses to a prime, led to the removal of this word pair from the stimulus list. In this way, it was established that none of the categorically related words were also associatively related.

5 Spatial (n=2), causal (n=5), functional (n=11) and possessive (n=1).

Additional information

Funding

This work was supported by the Special Research Fund (BOF) of Ghent University. The funding source was not involved in the study design, the collection, analysis and interpretation of the obtained data, or the writing of the manuscript.