Eve Fabre

In the field of aviation, a significant amount of accidents are attributable to a phenomenon called inattentional deafness, defined as “the propensity to remain unaware of unexpected, though fully perceptible auditory stimuli such as alarms”. The present study aimed at testing the impact of cognitive load on the perception of auditory information unrelated to the piloting task at stake in an ecological flight context. Pilots had to perform simultaneously a piloting task (i.e., approach and landing) in a A320 flight simulator and a passive auditory oddball task, with standard (80%) and deviant (20%) tones played. Lower N100 amplitudes were found in response to deviant tones when the piloting task was associated with a high cognitive load than a low cognitive load, demonstrating that cognitive load disrupts the perceptual processing of auditory stimuli, which is likely to trigger inattentional deafness in pilots

Given the important amount of visual and auditory linguistic information that pilots have to process, operating an aircraft generates a high working-memory load (WML). In this context, the ability to focus attention on relevant information and to remain responsive to concurrent stimuli might be altered. Consequently, understanding the effects of WML on the processing of both linguistic targets and distractors is of particular interest in the study of pilot performance. In the present work, participants performed a simplified p iloting t ask i n w hich t hey h ad t o f ollow o ne o f t hree colored aircraft, according to specific w ritten i nstructions (i.e., t he w ritten w ord f or t he color corresponding to the color of one of the aircraft) and to ignore either congruent or incongruent concurrent auditory distractors (i.e., a spoken name of color). The WML was manipulated with an n-back sub-task. Participants were instructed to apply the current written instruction in the low WML condition, and the 2-back written instruction in the high WML condition. Results revealed a major effect of WML at behavioral (i.e., decline of piloting performance), electrophysiological, and autonomic levels (i.e., greater pupil diameter). Increased WML consumed resources that could not be allocated to the processing of the linguistic stimuli, as indexed by lower P300/P600 amplitudes. Also, significantly, lower P600 responses were measured in incongruent vs. congruent trials in the low WML condition, showing a higher difficulty reorienting attention toward the written instruction, but this effect was canceled in the high WML condition. This suppression of interference in the high load condition is in line with the engagement/distraction trade-off model. We propose that P300/P600 components could be reliable indicators of WML and that they allow an estimation of its impact on the processing of linguistic stimuli.

Operating an aircraft is cognitively challenging: pilots have to control the plane and must remain responsive to potential verbal-auditory stimuli (e.g. Air Traffic Control Communication) and auditory alerts (e.g. Terrain Awareness and Warning System). Fifteen participants had to control an aircraft in order to target one of three differently-colored aircrafts displayed on a computer screen. The name of the color (written in black ink) corresponding to the aircraft to target was displayed in the center of the screen. Simultaneously with the onset of the written name of the color, a spoken color name distractor that participants had to ignore was played. This auditory distractor was either congruent (10%, spoken color name matched the written color) or incongruent (10%, spoken color name did not match the written color). The task difficulty varied in terms of working memory load with an n-back-like sub-task. In the low load condition, participants had to target the aircraft corresponding to the currently presented written instruction (n = 0). In the high load condition, participants had to target the aircraft corresponding to the instruction presented two trials before (n = 2). Behavioral analysis showed that increased mental workload provoked a decrease in piloting performance, i.e. participants tended to forget the correct instruction. On the physiological level, EEG/ERP measurements related to instructions showed that increased mental workload was accompanied by lower P3b amplitude. We assume that the lower P3b amplitude reflects the depletion of the cognitive resources allocated to the processing of the instructions. These results suggest that P3b can be a relevant indicator of the openness of the system to sudden and unexpected critical stimuli such as auditory alerts.

In the present event-related potential study, we investigated whether and how participants playing the ultimatum game as responders modulate their decisions according to the proposers' stereotypical identity. The proposers' identity was manipulated using occupational role nouns stereotypically marked with gender (e.g., Teacher; Engineer), paired with either feminine or masculine proper names (e.g., Anna; David). Greater FRN amplitudes reflected the early processing of the conflict between the strategic rule (i.e., earning as much money as possible) and ready-to-go responses (i.e., refusing unequal offers and discriminating proposers according to their stereotype). Responders were found to rely on a dual-process system (i.e., automatic and heuristic-based system 1 vs. cognitively costly and deliberative system 2), the P300 amplitude reflecting the switch from a decision making system to another. Greater P300 amplitudes were found in response to both fair and unfair offers and male-stereotyped proposers' offers reflecting an automatic decision making based on heuristics, while lower P300 amplitudes were found in response to 3€ offers and the female-stereotyped proposers' offers reflecting a more deliberative reasoning. Overall, the results indicate that participants were more motivated to engage in a costly deliberative reasoning associated with an increase in acceptation rate when playing with female-stereotyped proposers, who may have induced more positive and emphatic feelings in the participants than did male-stereotyped proposers. Then, we assume that people with an occupation stereotypically marked with female gender and engaged in an economic negotiation may benefit from their occupation at least in the case their counterparts lose their money if the negotiation fails.