PT  - JOURNAL ARTICLE
AU  - Leonie JT Balter
AU  - Jos A Bosch
AU  - Sarah Aldred
AU  - Mark T Drayson
AU  - Jet JCS Veldhuijzen van Zanten
AU  - Suzanne Higgs
AU  - Jane E Raymond
AU  - Ali Mazaheri
TI  - Unique Neurophysiological Vulnerability of Visual Attention Networks to Acute Inflammation
AID  - 10.1101/599159
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 599159
4099  - http://biorxiv.org/content/early/2019/04/04/599159.short
4100  - http://biorxiv.org/content/early/2019/04/04/599159.full
AB  - Illness is often accompanied by perceived cognitive sluggishness, a symptom that may stem from immune system activation. The current study used electroencephalography (EEG) to assess how inflammation affected three different distinct attentional processes: alerting, orienting and executive control. In a double-blinded placebo-controlled within-subjects design (20 healthy males, mean age = 24.5, SD = 3.4), Salmonella typhoid vaccination (0.025 mg; Typhim Vi, SanofiPasteur) was used to induce transient mild inflammation, while a saline injection served as a placebo-control. Participants completed the Attention Network Test with concurrent EEG recorded six hours post-injection. Analyses focused on behavioral task performance and on modulation of oscillatory EEG activity in the alpha band (9-12 Hz) for alerting as well as orienting attention and frontal theta band (4-8 Hz) for executive control. Vaccination induced mild systemic inflammation, as assessed by interleukin-6 (IL-6) levels. While no behavioral task performance differences between the inflammation and placebo condition were evident, inflammation caused significant alterations to task-related brain activity. Specifically, inflammation produced greater cue-induced suppression of alpha power in the alerting aspect of attention while individual variation in the inflammatory response was significantly correlated with the degree of alpha power suppression. Notably, inflammation did not affect orienting (i.e., alpha lateralization) or executive control (i.e., frontal theta activity). These results reveal a unique neurophysiological vulnerability to acute mild inflammation of the neural network that underpins attentional alerting functions. Observed in the absence of performance decrements, these novel findings suggest that acute inflammation requires individuals to exert greater cognitive effort when preparing for a task in order to maintain adequate behavioral performance.Highlights Typhoid vaccination induced a transient mild inflammatory stateMild inflammation alters neurophysiological process associated with attentionMild inflammation selectively increased alerting-related alpha suppression while behavior was unaffectedA greater inflammatory response was correlated with more alpha suppression