Neural Indices of Emotional Distraction

<p>Emotional stimuli capture our attention. The preferential processing of emotional information is an adaptive mechanism that when relevant to our goal highlights potentially important aspects in the environment. However, when emotional information is task-irrelevant, their presence in the environment can trigger involuntary shifts in attention that cause detriments to performance. One challenge to investigating emotional distraction in the lab is how to objectively investigate the allocation of attention between different elements on the same stimulus display (e.g. between the task and the distractors). One neural measure that overcomes this issue is the Steady-State-Visual-Evoked-Potential (SSVEP). An SSVEP is the neural response of the visual cortex to a flickering stimulus and can be used as a measure of attentional resource allocation (Norcia, Appelbaum, Ales, Cottereau, & Rossion, 2015). In the past, emotional distraction has been studied using spatially separated tasks and distractors. The current thesis presents two experiments using SSVEPs to investigate emotional distraction in a superimposed design. Experiment 1 aimed to conceptually replicate Hindi Attar and colleagues (2010) who developed an SSVEP emotional distraction paradigm to examine attentional resource allocation between background task-irrelevant emotional distractors and a foreground dot-motion task. Participants viewed a stimulus display of moving, flickering dots, while positive or neutrally valanced distractors (or unidentifiable scrambles) were presented in the background of the task. SSVEPs were reduced in the presence of positive intact compared to neutral intact distractors suggesting that the presentation of task-irrelevant emotional stimuli in the same spatial location as a foreground task initiates an involuntary shift of attention away from the task. Unexpectedly, in both Experiments 1 and 2 valence differences were found in SSVEPs between positive and neutral scrambled images; this suggests that there are some perceptual differences between the stimulus sets (e.g. colour) contributing to the drop in SSVEP found for positive intact images. Importantly, in the SSVEP analysis significant valence x image type interactions were found, demonstrating that the drop for positive images was stronger for intact than scrambled image conditions, suggesting that a significant amount of the drop in SSVEP was driven by a difference in valence between the intact distractors. Behavioural results also suggest evidence for emotional distraction through reduced hit rate in the presence of positive intact images compared to neutral intact images in Experiment 1, and reduced detection sensitivity and response criterion for positive intact images in Experiment 2. Overall, the current thesis demonstrates support for the hypothesis that emotional information is more distracting than neutral information and provides a valuable starting point for the examination of emotion attention interactions when the task and distractors share the same location. Future studies could use SSVEPs to examine neural processing differences between emotional and neutral scrambled images.</p>

Neural Indices of Emotional Distraction

<p>Emotional stimuli capture our attention. The preferential processing of emotional information is an adaptive mechanism that when relevant to our goal highlights potentially important aspects in the environment. However, when emotional information is task-irrelevant, their presence in the environment can trigger involuntary shifts in attention that cause detriments to performance. One challenge to investigating emotional distraction in the lab is how to objectively investigate the allocation of attention between different elements on the same stimulus display (e.g. between the task and the distractors). One neural measure that overcomes this issue is the Steady-State-Visual-Evoked-Potential (SSVEP). An SSVEP is the neural response of the visual cortex to a flickering stimulus and can be used as a measure of attentional resource allocation (Norcia, Appelbaum, Ales, Cottereau, & Rossion, 2015). In the past, emotional distraction has been studied using spatially separated tasks and distractors. The current thesis presents two experiments using SSVEPs to investigate emotional distraction in a superimposed design. Experiment 1 aimed to conceptually replicate Hindi Attar and colleagues (2010) who developed an SSVEP emotional distraction paradigm to examine attentional resource allocation between background task-irrelevant emotional distractors and a foreground dot-motion task. Participants viewed a stimulus display of moving, flickering dots, while positive or neutrally valanced distractors (or unidentifiable scrambles) were presented in the background of the task. SSVEPs were reduced in the presence of positive intact compared to neutral intact distractors suggesting that the presentation of task-irrelevant emotional stimuli in the same spatial location as a foreground task initiates an involuntary shift of attention away from the task. Unexpectedly, in both Experiments 1 and 2 valence differences were found in SSVEPs between positive and neutral scrambled images; this suggests that there are some perceptual differences between the stimulus sets (e.g. colour) contributing to the drop in SSVEP found for positive intact images. Importantly, in the SSVEP analysis significant valence x image type interactions were found, demonstrating that the drop for positive images was stronger for intact than scrambled image conditions, suggesting that a significant amount of the drop in SSVEP was driven by a difference in valence between the intact distractors. Behavioural results also suggest evidence for emotional distraction through reduced hit rate in the presence of positive intact images compared to neutral intact images in Experiment 1, and reduced detection sensitivity and response criterion for positive intact images in Experiment 2. Overall, the current thesis demonstrates support for the hypothesis that emotional information is more distracting than neutral information and provides a valuable starting point for the examination of emotion attention interactions when the task and distractors share the same location. Future studies could use SSVEPs to examine neural processing differences between emotional and neutral scrambled images.</p>

Emotion-Attention Interaction in the Right Hemisphere

Hemispheric asymmetries in affective and cognitive functions have been extensively studied. While both cerebral hemispheres contribute to most affective and cognitive processes, neuroscientific literature and neuropsychological evidence support an overall right hemispheric dominance for emotion, attention and arousal. Emotional stimuli, especially those with survival value such as threat, tend to be prioritized in attentional resource competition. Arousing unpleasant emotional stimuli have prioritized access, especially to right-lateralized attention networks. Interference of task performance may be observed when limited resources are exhausted by task- and emotion-related processing. Tasks that rely on right hemisphere-dependent processing, like attending to the left visual hemifield or global-level visual features, are especially vulnerable to interference due to attention capture by unpleasant emotional stimuli. The aim of this review is to present literature regarding the special role of the right hemisphere in affective and attentional brain processes and their interaction. Furthermore, clinical and technological implications of this interaction will be presented. Initially, the effects of focal right hemisphere lesion or atrophy on emotional functions will be introduced. Neurological right hemisphere syndromes including aprosodia, anosognosia and neglect, which further point to the predominance of the intact right hemisphere in emotion, attention and arousal will be presented. Then there will be a brief review of electrophysiological evidence, as well as evidence from patients with neglect that support attention capture by emotional stimuli in the right hemisphere. Subsequently, experimental work on the interaction of emotion, attention and cognition in the right hemispheres of healthy subjects will be presented. Finally, clinical implications for better understanding and assessment of alterations in emotion–attention interaction due to brain disorder or treatment, such as neuromodulation, that impact affective brain functions will be discussed. It will be suggested that measuring right hemispheric emotion–attention interactions may provide basis for novel biomarkers of brain health. Such biomarkers allow for improved diagnostics in brain damage and disorders and optimized treatments. To conclude, future technological applications will be outlined regarding brain physiology-based measures that reflect engagement of the right hemisphere in affective and attentional processes.

High fluid intelligence is characterized by flexible allocation of attentional resources: Evidence from EEG

Recently, the integrated control hypothesis (Lu et al., 2020) was proposed to explain the relationship between fluid intelligence (Gf) and attentional resource allocation. This hypothesis suggested that individuals with higher Gf tend to flexibly and adaptively allocate their limited resources according to the task type and task difficulty rather than simply exert more or fewer resources in any conditions. To examine this hypothesis, the present study used electroencephalogram (EEG) indicators (i.e., frontal theta-ERS and parietal-occipital alpha-ERD) as the measurement of participants’ resource allocation during the exploration task and exploitation task with different difficulties. The results found that higher Gf individuals tend to allocate fewer resources in all difficulty levels in the exploitation task compared to average Gf participants. In contrast, in the exploration task, higher Gf participants would allocate more resources in the medium- and high-difficulty levels than average Gf participants, but this phenomenon was only found in males. These findings provided supportive evidence for the integrated control hypothesis that flexible and adaptive attentional control ability are important characteristics of human intelligence.

Neurocognitive Effects of Self-Determined Choice and Emotional Arousal on Time Estimation

Even though effects of emotion and motivation on cognition are well documented, the interaction of all three factors is rarely investigated. Here, we used electroencephalography (EEG) to examine the effects of self-determined choice—as an experimental manipulation of intrinsic motivation - and emotional stimulus content on task preparation and engagement in a temporal production task. Behavioral results indicated a modulation of time processing depending on choice and emotional content. Underlying EEG signals revealed differential modulations by choice on the contingent negative variation (CNV) during task and response preparation and by emotional content on the late positive potential (LPP) in response to the onset of an emotional picture during temporal production. Also, we obtained preliminary evidence for interaction effects of choice and emotional content on the LPP. The feedback-related negativity (FRN) in response to information regarding temporal production success was also affected by interactions of choice and emotional content. These findings indicate that besides separate effects of motivation and emotion, there may be time windows during task engagement in which both factors jointly affect cognitive processing. These results are interpreted as dynamic modulations of attentional resource allocation.

Comparison of attentional resource allocation to threat and selfrelevant information: An event-related potentials study

Although previous researchers have shown that attention is preferentially allocated during situations involving both threat and selfrelevant information, it is unclear which information type requires more cognitive resources. We compared the automatic processing of threat and self-relevant stimuli using the no-report oddball paradigm. Participants looked at images on a computer screen that displayed fighting with opponents or interacting with friends or customers. The body action of the person depicted was performed either toward the viewing participant or toward other people. Participants watched without making an explicit response, and event-related potentials were measured with electroencephalography. We found that threat (vs. selfrelevant) information elicited a larger P300 amplitude, and for nonthreatening events the P300 amplitude was larger for self-relevant than other-relevant stimuli. These results indicate that threat (vs. selfrelevant) information demands more cognitive resources, possibly because people prioritize survival.

Tapping to hip-hop: Effects of cognitive load, arousal, and musical meter on time experiences

Experiences of time vary intra- and interindividually, depending on factors such as attentional resource allocation and arousal. Music as a temporal art that is structured by multiple temporal layers is ideal for investigating human time experiences. The current study used examples of hip-hop music that varied in arousal but were constant in tempo. Participants judged the passage of time to be quicker when cognitive load was high in a dual-task condition, and perceived duration to be shorter when performing a concurrent motor task (tapping along with the music). Perceived musical arousal did not affect subjective time. Attending to a higher metrical level by tapping with half notes resulted in shorter duration estimates and a quicker passage of time, compared to tapping with eighth notes of the same music. Results were not influenced by spontaneous motor tempo, musical expertise, preference or familiarity with the music. Taken together, these findings indicate consistent effects of cognitive load and attention to meter on time experiences.

Effect of Osteoarthritis on Prefrontal Cortical Activation Patterns During Downward Reaching in Older Women

Downward reaching may lead to falls in older adults, but the underlying mechanisms are poorly understood, particularly in older women with osteoarthritis. Given the importance of attentional resources when maintaining balance in balance-demanding conditions, functional near-infrared spectroscopy may provide a lens to the attentional resource allocation needed to maintain balance while reaching down to the ground with or without full contact with the floor. We examined the changes in the executive control of downward reaching movements in older women with osteoarthritis. We hypothesized that prefrontal cortical activation would be higher in older women with osteoarthritis, compared to age-matched controls, particularly as the balance demands increased. Older women with osteoarthritis (n=7, mean±SD age: 66±3 years) and age-matched controls (n=10, mean±SD age: 67±6 years) were recruited from the local community. The effect of the base of support and target position (toe or maximal forward distance along ground) on attentional resources in older women with osteoarthritis were evaluated using the average oxygenated hemoglobin levels as a measure of prefrontal cortical (PFC) activation. Significant base of support by cohort and target by cohort interactions were observed on average PFC activation levels (P&lt;0.005). As expected, PFC activation levels increased as the contact with the floor decreased and as the target distance increased, but older women with osteoarthritis were unable to increase their PFC activation levels as much as age-matched controls. In conclusion, these data suggest that older women with osteoarthritis may not be adequately modulating attentional resources to meet high-balance demanding tasks.