The effect of auditory feedback in an auditory Posner attention task: delay effect in ERP

The "Delay" is defined as the division of a signal in separate components, one of which is delayed, and then reintroduced into the original signal.Delay effect occurs when a subject hearsthe sound of his own voice which is delayed by a few milliseconds. This feedback induces difficulties in the articulation of language. We analyzed the effect on attention during training with natural auditory feedback and mechanical auditory feedback.If the stimulus is presented without delayed latency, natural feedback, the subjects will not have difficulty producing verbal language, the stimulus is presented with a delayed acoustic feedback. The subjects will present difficulties in languagearticulation , finding clear difficulty concentrating on what they are reading, or simply in the pronunciation of his name and surname. This highlights the momentary interruption of the automatic processes. After a short time with a change between 7 -10 minutes, there is a small habituation to the feedback whichis not natural. It would seem that with no natural feedback, the subject presents habituation to the delay effect. This parameter adjusts the time between the introduction of the original signal and the reintroduction of the delayed signal. The aim of this study was to investigate ERP correlation during an auditory Posner attention task afteran auditory delay effect training. We recruited a total of 20 university students (mean age 28.6) as test subjects. They had to perform a task whereby they had to say their personal information, read a lyric and sing. The training had a duration of 5 minutes. The delay time used in the experiment was 200 ms for all subjects undergoing experimental effect and 0 for those submitted in the control group. After the training an auditory Posner cueing task was administered during an EEG recording: a mono-aural pure tone pip (1000 Hz) presented unilaterally was used both as the cue (250 ms) and as the target. Cue-target asynchrony was either 100 or 600 ms. The spatial relationship between cue and target defined two conditions: valid target (the same location as the cue) and invalid target (opposite localization of the cue). A repeated-measures ANOVAwas performed on the amplitude and latency of N2 and P3. Main results of the study were on the N2 component in invalid target condition. The N2 component showed slower latencies in Fp1 (F= 7.105; p=0.015), Fp2 (F=7.901; p=0.011) F8 (F=4.877; p=0.039) and C3 (F=4.128; p=0.05) in the form of higher latency values in the delayed effect group. We found the same trend in Posner reaction time (behavioural results). Results of this work can indicate how auditory feedback systems alter motor and auditory attentional early processes thus altering not only the task itself in language performance (voice, prosody and spoken), but also the motor system in the subject reaction time, as well as some ERP’s components.