Recent work has proposed sliders as a useful way to measure self-reported emotion continuously. My dissertation extends this work to ask: what are relevant properties of affective self-report on sliders and variations? How reliable are affective self-reports? How do they relate to physiological data? What are individual and cultural differences? How can this method be applied to ehealth? Three emotion self-report tools (one-slider, two-slider, a touchscreen) were developed and evaluated in four experiments. The first experiment was within-subjects. Participants viewed short videos, with four self-report conditions (including no reporting) and physiological capture (heart rate variability and skin conductance). In a re-rating task, the sliders models were found to be more reliable than the touchscreen (Lottridge & Chignell, 2009a). The second and third experiments were between-subjects, and examined individual and cultural differences. Canadian and Japanese participants watched a nature video, while rating emotions and answering questions. Analyses were carried out within and across the datasets. Larger operation span displayed a minor benefit. Valence and arousal ratings were not strongly related to skin conductance. The Japanese performed on par with Canadians but reported worse performance. Based on the results, the recommendation was made that a single slider be used to rate valence, that arousal be estimated with skin conductance, and that slider psychometrics be used to assess cognitive load over time. In the fourth experiment, diabetic participants watched Diabetes-related videos. They clustered into usage patterns: some moved the slider very little during videos and more afterward, some hardly moved the slider, and some used it as expected. Two novel metrics facilitated these analyses: Emotional Bandwidth, an application of information entropy that characterizes the granularity of the self reports (Lottridge & Chignell, 2009b) and Emotional Majority Agreement, the amount of agreement relative to a sample’s self-reports (Lottridge & Chignell, 2009c). In summary, this dissertation contributes a method of measuring emotion through sliders and skin conductance that has been evaluated in a number of experimental studies. It contributes the empirical results, design recommendations, and two novel metrics of emotional response. Limitations and implications for future research and practice are also discussed.

Evolutionary accounts of empathy often focus on the ways in which empathy-motivated helping can give rise to indirect fitness benefits. These accounts posit that empathy is adaptive insofar as it motivates strategic helping behavior, but they neglect a key feature of the empathic process – it can prepare one to act effectively within a shared environment. In particular, adopting the affective and motivational states of others provides a rapid and automatic way to avoid danger and threat, which play a disproportionately large role in shaping behavior. Based on the idea that empathic processes facilitate adaptive reactions to threat, I conducted four experiments to test the hypothesis that empathic reactions reflect withdrawal motivation. In the first experiment I used electroencephalography (EEG) to measure baseline right-frontal cortical asymmetry, a reliable neural correlate of withdrawal motivation. I then assessed empathic reactions to images of children ostensibly taken from a charity campaign. Participants who showed greater right-frontal cortical asymmetry also showed stronger empathic reactions to the images. In the second study I used self-report measures fear and anger to assess dispositional withdrawal- and approach-motivation, respectively. This time, participants indicated their empathic reactions to targets experiencing happiness and targets experiencing sadness. Empathy for both types of targets was positively related to fear and negatively related to physical aggression, again supporting a link between empathy and withdrawal motivation. In the third study I measured state withdrawal motivation by using facial electromyography (EMG) to assess disgust expressions towards charity images. These expressions were positively correlated with empathic reactions, demonstrating that state withdrawal motivation is also positively related to empathy. In the final study I manipulated approach and withdrawal emotions by having participants make emotional facial expressions. Focusing on fear and anger, I found that participants were more empathic when making fearful faces than when making angry faces, although these results must be interpreted with caution, as the manipulation may not have had the intended effects on emotional state. Taken together, these four studies provide converging evidence of an association between withdrawal motivation and empathy, supporting the idea that empathy plays a role in the adaptive response to threat.

Alcohol and cannabis use are prevalent among young adults in Canada. Additionally, heavier substance use is associated with an increased likelihood of experiencing negative consequences resulting from use. Given the potential for harmful consequences resulting from alcohol and cannabis use, it is important to understand why people use these substances. Childhood maltreatment has been identified as an important predictor of alcohol and cannabis use. However, less is known about the mechanisms underlying this relationship, though it seems emotion regulation may play an important role. This study explores the relationship between maltreatment and emotion dysregulation, in addition to the relationship between maltreatment and affective motives for using alcohol and marijuana. Results indicate that drinking to cope mediates the relationship between all measured forms of maltreatment and alcohol consequences. However, none of the motives individually significantly mediated the relationship between maltreatment and marijuana use consequences. Results, limitations, and future directions are discussed.

To address the feasibility of ambulatory emotion recognition, characteristics of biosignals were compared between sitting and controlled walking using different stimulus modalities. Emotional stimulus items were drawn from the International Affective Pictures System and International Affective Digitized Sounds libraries to elicit five basic emotions. To assess which emotion was elicited, participants (n=15) completed self-report scales using the Self-Assessment Manikin and discrete emotion ratings following the presentation of each stimulus item. Autonomic activity was monitored using electrocardiogram, electrodermal activity, and thoracic and abdominal respiration. Multivariate analysis of variance was employed to test for differences in biosignal features and supervised classifiers were trained to predict the elicited emotion using physiological data. The study revealed differences between sitting and walking states but no effect was found for stimulus modality. Self-reported emotions were poorly predicted using our methodology and a discussion of potential directions and recommendations for future research was presented.

Impaired social interaction is one of the hallmarks of autism spectrum disorders (ASDs). Emotional faces are arguably the most critical visual emotional stimuli and the ability to perceive, recognize, and interpret emotions is central to social interaction and communication as well as healthy development. There is however, a paucity of studies devoted to neural and cognitive mechanisms underlying emotional face processing in adolescents with ASD. Through an implicit emotional face processing task completed in the MEG, we examined spatiotemporal differences in neural activation during angry and happy emotional face processing. Results suggest atypical frontal involvement in ASD adolescents during angry and happy face processing. In particular, orbitofrontal activation in participants with ASD was found to be delayed but greater in amplitude, relative to controls.

Alcohol and cannabis use are prevalent among young adults in Canada. Additionally, heavier substance use is associated with an increased likelihood of experiencing negative consequences resulting from use. Given the potential for harmful consequences resulting from alcohol and cannabis use, it is important to understand why people use these substances. Childhood maltreatment has been identified as an important predictor of alcohol and cannabis use. However, less is known about the mechanisms underlying this relationship, though it seems emotion regulation may play an important role. This study explores the relationship between maltreatment and emotion dysregulation, in addition to the relationship between maltreatment and affective motives for using alcohol and marijuana. Results indicate that drinking to cope mediates the relationship between all measured forms of maltreatment and alcohol consequences. However, none of the motives individually significantly mediated the relationship between maltreatment and marijuana use consequences. Results, limitations, and future directions are discussed.

To address the feasibility of ambulatory emotion recognition, characteristics of biosignals were compared between sitting and controlled walking using different stimulus modalities. Emotional stimulus items were drawn from the International Affective Pictures System and International Affective Digitized Sounds libraries to elicit five basic emotions. To assess which emotion was elicited, participants (n=15) completed self-report scales using the Self-Assessment Manikin and discrete emotion ratings following the presentation of each stimulus item. Autonomic activity was monitored using electrocardiogram, electrodermal activity, and thoracic and abdominal respiration. Multivariate analysis of variance was employed to test for differences in biosignal features and supervised classifiers were trained to predict the elicited emotion using physiological data. The study revealed differences between sitting and walking states but no effect was found for stimulus modality. Self-reported emotions were poorly predicted using our methodology and a discussion of potential directions and recommendations for future research was presented.

Impaired social interaction is one of the hallmarks of autism spectrum disorders (ASDs). Emotional faces are arguably the most critical visual emotional stimuli and the ability to perceive, recognize, and interpret emotions is central to social interaction and communication as well as healthy development. There is however, a paucity of studies devoted to neural and cognitive mechanisms underlying emotional face processing in adolescents with ASD. Through an implicit emotional face processing task completed in the MEG, we examined spatiotemporal differences in neural activation during angry and happy emotional face processing. Results suggest atypical frontal involvement in ASD adolescents during angry and happy face processing. In particular, orbitofrontal activation in participants with ASD was found to be delayed but greater in amplitude, relative to controls.

It is widely thought that emotional stimuli receive privileged neural status compared to their non-affective counterparts. This prioritization, however, comes at a cost, as the neural capacity of the human brain is finite; the prioritization of any one object comes at the expense of other concurrent objects in the visual array competing for awareness (Desimone & Duncan, 1995). Despite this reality, little work has examined the functional benefit derived from the perceptual prioritization of affective information. Why do we preferentially attend to emotional faces? According to evolutionary accounts, emotions originated as adaptations towards action, helping to prepare the organism for movement (Darwin, 1872; Frijda, 1986). The current dissertation examines this from the perceptive of visual neuroscience and motor cognition. Chapters 1 and 2 examine the mechanisms involved during the perceptual prioritization of emotional content in the context of action system modulation. Chapters 3 and 4 then directly examine emotions effect on oculomotor action output. Results across the studies are discussed in the context of evolutionary theories related to biological origins of emotional expression.

According to socioemotional selectivity theory (SST), old age is associated with a greater emphasis on self-regulation of emotional states, a focus that fosters a bias in processing positively valenced material in older adults. There is disagreement, however, about whether the “positivity bias” suggested by SST influences performance on memory tasks. Some studies suggest that older adults remember more positive than negative information, or simply less negative information, relative to younger adults, whereas other studies report no such differences. This thesis examined (1) whether variations across studies in encoding instructions or in personal relevance of study materials could account for these inconsistencies, and (2) whether differences in attention at encoding to positive, negative, and neutral stimuli could account for the positivity bias in older adults’ later memory for the stimuli. In Experiment 1, younger and older adults were instructed either to passively view positive, negative, and neutral pictures or to actively categorize them by valence. On a subsequent incidental recall test, older adults recalled equal numbers of positive and negative pictures, whereas younger adults recalled negative pictures best. There was no effect of encoding instructions. Crucially, when pictures were grouped into high and low personal relevance according to participants’ ratings, a positivity bias emerged only for low relevance pictures. In Experiment 2, attention to pictures at encoding was directly manipulated through use of a divided attention paradigm. Although divided attention lowered recall in both age groups, attention did not interact with age and valence. Taken together, the results suggest that variability in the personal relevance of study pictures may be the factor underlying cross-study differences in whether a positivity bias is observed in older adults’ memory.