Phasic alerting increases visual attention capacity in younger but not in older individuals

ABSTRACT

In the present study, we investigated effects of phasic alerting on visual attention in younger and older adults. We modelled parameters of visual attention based on the computational Theory of Visual Attention (TVA) and measured event-related lateralizations (ERLs) in a partial report task, in which half of the displays were preceded by an auditory warning cue. Younger adults showed an alertness-related visual processing facilitation: TVA parameter sensory effectiveness a, a measure of visual processing capacity, was significantly increased, and latencies of visual ERLs were significantly reduced following the warning cue. By contrast, older adults did not benefit from the alerting cue: TVA parameter sensory effectiveness a and ERL latencies did not differ between conditions with and without cues. The findings indicate age-related changes in the brain network underlying alertness and attention, which governs the responsiveness to external cues and is critical for general cognitive functioning in aging.

KEYWORDS:

• Cognitive aging
• arousal
• visual attention
• event-related potentials
• warning cue
• noradrenaline

Acknowledgements

We would like to thank Christine Lykke Knudsen, Jon Lansner, and Trine Walsted Jessen for their help with the data assessment, and Bart Cooreman for help with the EEG data processing. We thank Sander Los and an anonymous reviewer for their helpful comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Iris Wiegand http://orcid.org/0000-0003-2160-7939

Notes

1. The analyses on the TVA parameter estimates revealed the same results when participants with bad EEG data quality were included (five younger and 10 older participants): For parameter sensory effectiveness a, there was a main effect of Alerting [F(1,48) = 11.65, p < .01, ${\eta }_{\mathrm{p}}^2=.20$], and a significant interaction of Alerting and Age [F(1,48) = 5.01, p = .03, ${\eta }_{\mathrm{p}}^2=.10$], resulting from a significant alerting effect in the younger group [F(1,22) = 17.29, p < .001], but not in the older group [F(1,26) = 0.67, p = .42]. For parameters top-down control α and spatial bias w_index, there were no significant main effects of alerting, or age, or interaction of the factors [all Fs < 1.30; all ps > .25].

2. Note that mere sensory deficits are not a likely explanation for the absent alerting effect in the present study, since auditory perception thresholds were normal on an audiometric screening test, and individual hearing thresholds did not correlate significantly with the alerting effect on sensory effectiveness in the older group [r = −.26, p = .31].

Additional information

Funding

This research was supported by a DFF MOBILEX Mobility Grant from the Danish Council for Independent Research, co-funded by the European Union Marie-Sklodowska Curie Actions (IW), a European Union Marie-Sklodowska Curie Initial Training Network grant (606901, AP and CB), and a Sapere Aude DFF Starting Grant from the Danish Council for Independent Research (TH); Det Frie Forskningsråd; Seventh Framework Programme.