Project ID
SSA
Expected experimentation period
Start date: 13/11/2020
End date: 19/07/2021
Experimental location
Laval University, Quebec, QC
Task Description
Participants were scheduled for two sessions lasting approximately an hour and a half each (52 min of experiment and approximately 30 min of EEG preparation and set-up). Over the two sessions, participants went through twelve 8-min blocks of an oddball paradigm with time intervals. Each 52-min session consisted of 6 blocks. Each block was separated by a 3-min break. The task consisted in a passive listening of an auditory oddball paradigm; eyes opened with a fixation cross displayed on the screen. For each block, 40 trials of 10 sounds were presented for each condition (below and above 1.2 s). It is relevant to note that all trials were presented continuously without inter-trial intervals, which results in a continuous flow of stimuli (corresponding to a classic oddball paradigm). For each trial, a deviant empty time interval appearing between sounds was pseudo-randomly presented across the standard empty time intervals. The standards and deviants are referring to empty time intervals presented. In a series of 10 empty time intervals, 9 empty time intervals were “standards” (which corresponded to 0.8 s in the < 1.2-s condition, and 1.6 s in the > 1.2-s condition) and one was “deviant” (the empty time interval was either shorter/early) or longer/delayed). There was a repetition of at least 4 standard time intervals before a deviant time interval was presented. For half of the blocks, the < 1.2-s condition trials were presented first, and for the other half, the > 1.2-s condition trials were presented first. The deviant empty time interval for each sequence of ten empty time intervals was selected at random. The deviant empty time intervals were either early (< 1.2 s: 0.70, 0.75 s; > 1.2 s: 1.4, 1.5 s) or delayed (< 1.2 s: 0.85, 0.9 s; > 1.2 s : 1.7, 1.8 s) as compared to the empty standard interval. Empty time intervals, by opposition to filled intervals, were used to avoid auditory fatigue. Furthermore, for the range of durations used in the current experiment, empty intervals are at least as easily discriminated as filled intervals. This resulted in 60 deviants for each condition. Note that 60 standard trials were randomly selected to perform contrasts between deviant and standard (see below). The participants were instructed to listen to the different sounds that would be presented. All sounds were 5 kHz and lasted 30 ms, with a 10-ms ascending-descending envelope. Presentation software (Neurobehavioral Systems, Albany, CA, USA) was used for the delivery of the experimental protocol and to trigger auditory stimuli. The sounds were presented with Audiotechnica ATH-M50x at 70 dB (SPL). For the six blocks of one given session, the < 1.2-s condition and the > 1.2-s condition were presented in alternation; and then the opposite sequence was adopted for the six blocks of the other session. Auditory event-related potentials (ERP) for each condition were then studied at the sensors and source levels.
Participant categories
Twenty healthy participants (10 females and 10 males; mean age, 23.15; SD, 1.50; age range; 21–27, mean education, 17.63 years; SD, 2.16; education range, 14–22 years; 17 right-handed and 3 left-handed), all with normal hearing, no history of neurological or psychiatric disorders, gave their informed consent to participate in this study and received monetary compensation for their participation.
Trigger channels
n/a
Events
- Mk
- S 1
- S 2
- S 3
- S 4
- S 5
- S 6
- S 7
- S 8
- S 9
- S 10
- S 20
Primary Publication
Thibault, N., Albouy, P. & Grondin, S. Distinct brain dynamics and networks for processing short and long auditory time intervals. Sci Rep 13, 22018 (2023). https://doi.org/10.1038/s41598-023-49562-8
Acknowledgements
Fonds de Recherche du Québec – Santé, National Sciences and Engineering Research Council of Canada Discovery, Brain Canada
Contact Person
Nicola Thibault: nicola.thibault.1@ulaval.ca