Table 1.
SEM, standard error of the mean; f, female; m, male; r, right-handed.
Fig 1.
Top row. Example of an informative trial with no distracting sound: a one-sided visual cue (200 ms duration) indicated in which ear (left or right) the target sound would be played (100 ms duration) after a fixed 1000-ms delay. Bottom row. Example of an uninformative trial with a distracting sound: a two-sided visual cue (200 ms duration) did not provide any indication in which ear (left or right) the target sound will be played. In 25% of the trials, a binaural distracting sound (300 ms duration), such as a clock ring, was played during the delay between cue and target. The distracting sound could equiprobably onset in two different time periods after the cue offset: in the 50–350 ms range, or in the 350–650 ms range.
Fig 2.
Outline of the analysis pipeline.
Fig 3.
Percentage of incorrect responses averaged across cue conditions, according to distractor conditions, for both groups.
*** P < 0.001. Error bars represent SEM.
Fig 4.
(A) Median RTs in each group according to cue information and distractor conditions. Error bars represent SEM. Boxplots of the Distraction cost (B), the Arousal benefit (C), and the Cue benefit (D), for each group. Within each boxplot (Tukey method), the horizontal line represents the median, the box delineates the area between the first and third quartiles (interquartile range). ** P < 0.01.
Fig 5.
Comparison between post-cue activity of interest (between 0 and 1.2s post-cue and 5-45Hz) to baseline (-0.6 to -0.2s pre-cue) for young and elderly participants. A-C. Topographical maps represent T-values, masked at p < 0.1, for the comparison in the alpha band (7–15 Hz and 0.6-1s post-cue). B-D. Time-frequency representations depict T-values, of the same tests, masked at p<0.1 and averaged across sensors highlighted by black boxes on the corresponding topographical maps.
Fig 6.
A-B. Distributions of T-values, masked at p < 0.05, from cluster-based permutation tests contrasting time-frequency windows of interest (low and high alpha) against baseline activity at the source level for each group. C. Distributions of T-values, masked at p < 0.05, from cluster-based permutation tests contrasting baseline-corrected time-frequency window of interest between groups. Yellowish/blueish colors indicate a greater activity in the young/elderly group, respectively.
Fig 7.
Individual alpha peak frequency in virtual ROIs (averaged across hemispheres) for each group.
* p < 0.05, ** p < 0.01. Within each boxplot (Tukey method), the horizontal line represents the median of iAPF, the box delineates the area between the first and third quartiles (interquartile range).
Table 2.
Significant results of the lme model testing the modulation of alpha activity by group, cue condition, ROI modality and hemisphere.
Fig 8.
Mean alpha power (relative to baseline) centered around the alpha-peak frequency for each region and each participant, averaged between 600 and 1000 ms (post-cue onset) for each cue condition.
*P < 0.05, **P < 0.01, ***P < 0.001. Error bars represent SEM.
Fig 9.
Upper row: Topographical maps averaged between 50–110 Hz and 0–0.35 seconds post-distractor onset, of the T-values, masked at p < 0.05 of the contrast between distractor and surrogate distractor gamma activity for each group. Lower row: Time-frequency representations of T-values (of the aforementioned test) of the sensors highlighted by red boxes. Note that each TF plot is surrounded by the frequency distribution of T-values of the aforementioned sensors averaged across the time dimension and by the time distribution of T-values of the aforementioned sensors averaged across the frequency dimension.
Fig 10.
A&B. Distributions of T-values, masked at p<0.05, from Cluster Based Permutation tests contrasting real and surrogate distractor gamma activity (60-100Hz and 0.1–0.3 post-distractor) for elderly and young groups, respectively, at the source level. C. Between group comparison of surrogate-corrected distractor gamma activity (60-100Hz and 0.1–0.3 post-distractor) at the source level. Positive T-values indicate stronger gamma activity in the young group. Yellowish/blueish colors indicate a greater activity in the young/elderly group, respectively. D. Between cue condition comparison of surrogate-corrected gamma activity to distractor in the young group. Positive T-values indicate stronger gamma activity in the informative cue condition. Yellowish/blueish colors indicate a greater activity in the informative/uninformative condition, respectively. Note that no significant effect was found in the elderly group.