Busy and confused? High risk of missed alerts in the cockpit: An electrophysiological study

The ability to react to unexpected auditory stimuli is critical in complex settings such as aircraft cockpits or air traffic control towers, characterized by high mental load and highly complex auditory environments (i.e., many different auditory alerts). Evidences show that both factors can negatively impact auditory attention and prevent appropriate reactions. In the present study, 60 participants performed a simulated aviation task varying in terms of mental load (no, low, high) concurrently to a tone detection paradigm in which the complexity of the auditory environment (i.e., auditory load) was manipulated (1, 2 or 3 different tones). We measured both detection performance (miss, false alarm, d’) and brain activity (event-related potentials) associated with the target tone. Our results showed that both mental and auditory loads affected target tone detection performance. Importantly, their combined effects had a large impact on the percentage of missed target tones. While, in the no mental load condition, miss rate was very low with 1 (0.53%) and 2 tones (1.11%), it increased drastically with 3 tones (24.44%), and this effect was accentuated as mental load increased, yielding to the higher miss rate in the 3-tone paradigm under high mental load conditions (68.64%). Increased mental and auditory loads and miss rates were associated with disrupted brain responses to the target tone, as shown by reduced P3b amplitude. In sum, our results highlight the importance of balancing mental and auditory loads to maintain efficient reactions to alarms in complex working environment

Explicit processing of verbal and spatial features during letter-location binding modulates oscillatory activity of a fronto-parietal network.

The present study investigated the binding of verbal and spatial features in immediate memory. In a recent study, we demonstrated incidental and asymmetrical letter-location binding effects when participants attended to letter features (but not when they attended to location features) that were associated with greater oscillatory activity over prefrontal and posterior regions during the retention period. We were interested to investigate whether the patterns of brain activity associated with the incidental binding of letters and locations observed when only the verbal feature is attended differ from those reflecting the binding resulting from the controlled/explicit processing of both verbal and spatial features. To achieve this, neural activity was recorded using magnetoencephalography (MEG) while participants performed two working memory tasks. Both tasks were identical in terms of their perceptual characteristics and only differed with respect to the task instructions. One of the tasks required participants to process both letters and locations. In the other, participants were instructed to memorize only the letters, regardless of their location. Time–frequency representation of MEG data based on the wavelet transform of the signals was calculated on a single trial basis during the maintenance period of both tasks. Critically, despite equivalent behavioural binding effects in both tasks, single and dual feature encoding relied on different neuroanatomical and neural oscillatory correlates. We propose that enhanced activation of an anterior–posterior dorsal network observed in the task requiring the processing of both features reflects the necessity for allocating greater resources to intentionally process verbal and spatial features in this task

Oscillatory activity in prefrontal and posterior regions during implicit letter-location binding.

Many cognitive abilities involve the integration of information from different modalities, a process referred to as “binding.” It remains less clear, however, whether the creation of bound representations occurs in an involuntary manner, and whether the links between the constituent features of an object are symmetrical. We used magnetoencephalography to investigate whether oscillatory brain activity related to binding processes would be observed in conditions in which participants maintain one feature only (involuntary binding); and whether this activity varies as a function of the feature attended to by participants (binding asymmetry). Participants performed two probe recognition tasks that were identical in terms of their perceptual characteristics and only differed with respect to the instructions given (to memorize either consonants or locations). MEG data were reconstructed using a current source distribution estimation in the classical frequency bands. We observed implicit verbal–spatial binding only when participants successfully maintained the identity of consonants, which was associated with a selective increase in oscillatory activity over prefrontal regions in all frequency bands during the first half of the retention period and accompanied by increased activity in posterior brain regions. The increase in oscillatory activity in prefrontal areas was only observed during the verbal task, which suggests that this activity might be signaling neural processes specifically involved in cross-code binding. Current results are in agreement with proposals suggesting that the prefrontal cortex function as a “pointer” which indexes the features that belong together within an object

Directed forgetting in frontal patients' episodic recall

The aim of this study was to examine the performance of a group of patients with lesions of the prefrontal cortex in directed forgetting in episodic memory, i.e. the capacity to actively forget irrelevant information. Four lists of 24 intermixed to-be-remembered (TBR) and to-be-forgotten (TBF) words were presented for retention. Restricted (TBR only) and unrestricted (TBR and TBF) recall were tested. The results showed that prefrontal patients presented with a general reduction in episodic memory but a normal ability to selectively recall the TBR items during restricted and unrestricted recall. These results are consistent with previous reports of intact directed forgetting in frontal patients and are discussed in terms of their implications for the current debate on the neural substrate of executive functions. © 2006 Elsevier Ltd. All rights reserved

Busy and confused? High risk of missed alerts in the cockpit: An electrophysiological study

International audienc

'What's in a name?' ‘No more than when it's mine own’. Evidence from auditory oddball distraction

Research of the distractor value of hearing the own name has shown that this self-referring stimulus captures attention in an involuntary fashion and create distraction. The behavioral studies are few and the outcomes are not always clear cut. In this study the distraction by own name compared to a control name was investigated by using a cross-modal oddball task in two experiments. In the first experiment, thirty-nine participants were conducting a computerized categorization task while exposed to, to-be ignored own and matched control names (controlling for familiarity, gender and number of syllables) as unexpected auditory deviant stimulus (12.5% trials for each name category) and a sine wave tone as a standard stimulus (75% of the trials). In the second experiment, another group of thirty-nine participants completed the same task but with the additional deviant stimulus of an irrelevant word added (10% trials for each deviant type and 70% trials with the standard stimulus). Results showed deviant distraction by exposure to both the irrelevant word, own and the control name compared to the standard tone but no differences were found showing that the own name captured attention and distracted the participants more than an irrelevant word or a control name. The results elucidate the role of the own name as a potent auditory distractor and possible limitations with its theoretical significance for general theories of attention are discussed