Joint Analysis of Eye Blinks and Brain Activity to Investigate Attentional Demand during a Visual Search Task

Abstract

In several fields, the need for a joint analysis of brain activity and eye activity to investigate the association between brain mechanisms and manifest behavior has been felt. In this work, two levels of attentional demand, elicited through a conjunction search task, have been modelled in terms of eye blinks, brain activity, and brain network features. Moreover, the association between endogenous neural mechanisms underlying attentional demand and eye blinks, without imposing a time-locked structure to the analysis, has been investigated. The analysis revealed statistically significant spatial and spectral modulations of the recorded brain activity according to the different levels of attentional demand, and a significant reduction in the number of eye blinks when a higher amount of attentional investment was required. Besides, the integration of information coming from high-density electroencephalography (EEG), brain source localization, and connectivity estimation allowed us to merge spectral and causal information between brain areas, characterizing a comprehensive model of neurophysiological processes behind attentional demand. The analysis of the association between eye and brain-related parameters revealed a statistically significant high correlation (R > 0.7) of eye blink rate with anterofrontal brain activity at 8 Hz, centroparietal brain activity at 12 Hz, and a significant moderate correlation with the participation of right Intra Parietal Sulcus in alpha band (R = −0.62). Due to these findings, this work suggests the possibility of using eye blinks measured from one sensor placed on the forehead as an unobtrusive measure correlating with neural mechanisms underpinning attentional demand.

The Sample Size Matters: To What Extent the Participant Reduction Affects the Outcomes of a Neuroscientific Research. A Case-Study in Neuromarketing Field

“…In fact, thanks to the increasing shared knowledge and recent scientific evidence produced by the neuroscientific community, behavioural neuroscience is experiencing an exponential growth in terms of applied research [ 13 , 14 , 15 ]. Recently, new terms have been coined, such as Neuroergonomics, Neuromarketing, Neuroaesthetics, and others, to include the new neuroscientific disciplines that aim at investigating neurophysiological correlates of humans’ behaviour at work [ 16 , 17 , 18 ], including driving a car [ 19 , 20 , 21 , 22 , 23 , 24 ], watching television [ 25 , 26 , 27 ], having a sensorial experience [ 28 , 29 , 30 ], and in any other activity of daily life. In the context of applied neurosciences, when physiological signals are acquired in real environments, several factors work against the ease of participant recruitment.…”

“…This number was deemed appropriate to assume the results were reliable, i.e., representative of the theorical population, in line with the scientific literature [32]. These subgroups were chosen since: (i) in the literature there is a large consensus considering [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] the optimal range of participants in neuroimaging studies [33]; (ii) in order to perform Analysis of Variance, the number of cases (i.e., 630) has to be much higher than the number of groups (i.e., five). The experimental task consisted of watching four TV spots with different lengths (30,30,20, and 15 s) during which electroencephalographic (EEG) signal and autonomic measures, i.e., heart rate (HR) and galvanic skin response (GSR), were acquired.…”

Evaluation of a New Lightweight EEG Technology for Translational Applications of Passive Brain-Computer Interfaces

“…From the neurophysiological point of view, vigilance-related processes involve mainly the right inferior frontal brain regions (Di Flumeri et al, 2019b ; Sebastiani et al, 2020 ; Sciaraffa et al, 2021 ). Increased frontal activity in the beta band, more in right than in the left hemisphere, is correlated with vigilance decrement (Molina et al, 2013 ).…”

Air Force Pilot Expertise Assessment during Unusual Attitude Recovery Flight

“…In this regard, recent advances in neuroimaging techniques, such as functional Magnetic Resonance Imaging (fMRI), Regional Cerebral Blood Flow (rCBF), Positron Emission Tomography (PET), Magnetoencephalogram (MEG) and Electroencephalogram (EEG) allow cognitive processing and its neural correlates to be studied noninvasively in humans. For example, efforts have been made to use these techniques to examine brain regions involved in calculation [20,21], long term potentiation [22], encoding of new information [23,24], successful maintenance of information in memory [25], performance monitoring [26][27][28][29], attention [30][31][32] and working memory [33][34][35][36][37][38][39][40]. All these aspects are linked to mental effort.…”

“…In this regard, a higher number of recovery maneuvers will be inserted in the next experimental protocol to obtain a proper number of observations and to be able to evaluate correlations between URTs and other parameters, such as the MEF (neurophysiological data) and LIK scores (subjective data). Finally, additional neurophysiological signals, such as a pilot's Electrodermal activity (EDA), can be collected for considering more mental (Mental Fatigue [80][81][82][83], Stress [68], Attention [32], cognitive control behavior [76]) and emotional aspects [84,85] when comparing Expert and Novice pilots.…”