Fig. 3: Effect of difference of SSVEP power across hemifields (ΔΦ) on target d′.
From: Tracking momentary fluctuations in human attention with a cognitive brain-machine interface
a Mean target Φ (top) and distractor Φ (bottom) traces for high-Φ (blue) and low-Φ (red) target triggered trials, as well as non-triggered trials (gray), time-locked to the presentation of the grating stimuli (dashed vertical line). Shaded region: s.e.m. b (i) d′ values (dots) based on a median split of ΔΦ for high-Φ, target side triggered trials. Extreme (Ext) +ΔΦ and moderate (Mod) ΔΦ refer to ΔΦ values greater than and less than the median, respectively. Open and filled circles: Trials triggered based on left- and right-hemifield Φ values, respectively. Black dot and error bar: Mean effect size and 95% confidence interval, respectively, for the difference between d′ across Ext +ΔΦ and Mod ΔΦ trials. Gray histogram: bootstrap sampling distribution for effect size. Dashed horizontal line: Datum indicating zero effect size. (Inset) ΔΦ distribution for Extreme +ΔΦ (light, solid line) and Moderate ΔΦ (light, dashed line) subsets for high Φ trials. Dark lines: Curve fits based on a kernel density estimate. (ii–iv) Same as in the top left panel, but showing median split results for low-Φ target side triggered trials, high-Φ distractor side triggered trials and low-Φ distractor side triggered trials, respectively.
