The Aesthetic and Economic Value of Social and Non-Social Stimuli Seen from an Eye-Tracker : Pupillary Changes and Eye Fixations can Index the Aesthetic Value of HumanFaces as well as of Wine Labels

Abstract The present study examines the effect that hedonic value can have on economic decisions (e.g., willingness to pay) as well as oculomotor behavior and pupillary responses (i.e., measures of the allocation of attention). Due to the well-known interactions between reward circuitry in the brain, modes of activity in the LC, and pupillary dilations (Aston-Jones & Cohen, 2005; Laeng, et al., 2012), pupillometry with eye tracking should be a promising method to study the effect of hedonic stimuli. To our knowledge, no previous study has provided evidence that changes in the eye pupil’s diameter can index parametrically the hedonic response (i.e., proportionally to the level of attractiveness of either social or non-social stimuli). Specifically, pupillary changes along with eye fixations of 49 participants were monitored while they were viewing images of either human faces or wine bottles. Both sets of stimuli had initially being rated by an independent group of 80 participants for their hedonic value. Participants made economic decisions by estimating either price or salary that participants would be willing to give for each wine bottle or person, respectively. Results showed a linear increase in pupil dilations in response to parametric increases in facial attractiveness, whereas non-linear, i.e. U-shaped, pupillary changes were registered in response to wine labels. Moreover, above median level of attractiveness in faces and wine labels triggered, respectively, smaller and greater numbers of eye fixations. The data from economic decisions revealed a linear increase in the level of offered monetary payoffs as a function of hedonic level for both faces and wine labels. Areas of interest analyses revealed the visual features that attracted the most attention and a left-side laterality effect. Finally, only facial attractiveness showed gender-dependent effects on both economic decisions and biological responses

Measurement invariance of the moral vitalism scale across 28 cultural groups

Moral vitalism refers to a tendency to view good and evil as actual forces that can influence people and events. The Moral Vitalism Scale had been designed to assess moral vitalism in a brief survey form. Previous studies established the reliability and validity of the scale in US-American and Australian samples. In this study, the cross-cultural comparability of the scale was tested across 28 different cultural groups worldwide through measurement invariance tests. A series of exact invariance tests marginally supported partial metric invariance, however, an approximate invariance approach provided evidence of partial scalar invariance for a 5-item measure. The established level of measurement invariance allows for comparisons of latent means across cultures. We conclude that the brief measure of moral vitalism is invariant across 28 cultures and can be used to estimate levels of moral vitalism with the same precision across very different cultural settings.Peer reviewe

Another look at category effects on colour perception and their left hemispheric lateralisation: no evidence from a colour identification task

The present study aimed to replicate category effects on colour perception and their lateralisation to the left cerebral hemisphere (LH). Previous evidence for lateralisation of colour category effects has been obtained with tasks where a differently coloured target was searched within a display and participants reported the lateral location of the target. However, a left/right spatial judgment may yield LH-laterality effects per se. Thus, we employed an identification task that does not require a spatial judgment and used the same colour set that previously revealed LH-lateralised category effects. The identification task was better performed with between-category colours than with within-category task both in terms of accuracy and latency, but such category effects were bilateral or RH-lateralised, and no evidence was found for LH-laterality effects. The accuracy scores, moreover, indicated that the category effects derived from low sensitivities for within-blue colours and did not reflect the effects of categorical structures on colour perception. Furthermore, the classic "category effects" were observed in participants\u27 response biases, instead of sensitivities. The present results argue against both the LH-lateralised category effects on colour perception and the existence of colour category effects per se

Individual differences in tonic and phasic pupillary indices of cognitive abilities: Preliminary evidence for a task- and state-specific account

The present thesis gathers findings from three empirical studies in which we examined the cognitive basis of individual differences in phasic and tonic pupil cognitive responses. Some previous studies have reported a positive relationship between tonic and phasic pupil sizes and cognitive traits, such as general intelligence (gF) and working memory capacity. However, other studies have shown either a negative or no relationship. These findings have been usually accounted for by relatively stable differences in the function of the brain’s locus-coeruleus norepinephrine (LC-NE) system and in how much mental resources highly intelligent individuals have or how efficiently they are able to allocate their resources in general. Our findings, however, challenge these accounts and indicate that individual differences in pupil cognitive responses are driven by the task- and state-specific cognitive factors rather than general cognitive traits. In other words, the pupillary responses in both MOT and Posner tasks showed that the high performers had larger TEP sizes than low task performers, but only when the task was very demanding and more mental effort was required. When the task was not very demanding, high performers seemed more efficient in the allocation of their resources since they outperformed the low performers without investing more resources (i.e., no significant difference in TEP sizes between groups). These results may indicate that the neuromodulatory function of the LC-NE system is mediated by individuals’ level of cognitive functioning in a specific state and task. These differences may also have visual consequences, especially in the real-life situations, by modulating the trade-off between visual sensitivity and acuity in a statespecific fashion. The cognitive correlates of individual differences in tonic baseline pupil sizes also seemed to also be state- and task-specific. That is, we found a positive relationship between mean pretrial baselines and overall performance, but only in the MOT task. Also, none of the indices of general cognitive abilities were related to the average size of resting-state or pretrial baseline pupil sizes. WMC, however, was positively related to the coefficient of variation of resting-state baselines. This higher variability may be accompanied with a more dynamic and explorative mode to search randomly for internal or external rewarding sources. But it may also reflect the arousal-related regulations. Results also showed a stable effect of aging. In fact, it seems that differences in sample characteristics and methodological factors can be of important factors when studying the cognitive correlates of individual differences in pupil sizes. These findings are important for our understanding of pupillary cognitive responses and for developing better theoretical accounts. These findings can also contribute to expanding the potential application of pupillometry. For example, in combination with machine learning, it may be possible to adjust the demanding level of the cognitive tasks based on the changes in behavioral and pupillary responses and track individuals’ cognitive progression in educational settings and therapeutic interventions at the individual level

A delayed discrimination task yields categorical perception of color not only in the right but also in the left visual field

Photograph of crossbedding in De Chelly sandstone, Monument uplift, Arizona, 1914. Photo 920 from Herbert E. Gregory Book 7: Navajo, 1913, 1914

Pupillary and behavioral markers of alerting and orienting: An individual difference approach

Measuring task-evoked pupillary (TEP) responses as an index of phasic activity in the locus coeruleus (LC), we examined two competing hypotheses regarding the alerting and orienting mechanisms of attention. According to a dual mechanism account (Fernandez-Duque & Posner, 1997), two separate noradrenergic and cholinergic mechanisms modulate, respectively, the alerting and orienting effects. However, Corbetta and colleagues (2008) proposed that LC phasic activity may also be involved in orienting effect through its functional relationship with the ventral attentional network. We recruited seventy-five healthy Norwegian participants to perform a Posner cueing task. Both behavioral and pupillary responses revealed the alerting effect. Also, both behavioral and pupillary responses indicated that cued attention is affected by age. Behavioral responses also revealed orienting effect However, we found no TEP differences between valid, invalid, and neutral conditions, suggesting that TEP effects were driven by the alerting effect of cue presentation. Moreover, both behavioral and pupillary estimates of alertness and orienting were uncorrelated. Finally, individual differences in general cognitive abilities did not appear to affect the orienting and alerting mechanisms. This pattern of results is consistent with the dual mechanism account of attention. However, the LC involvement in the (re)orienting attention may be driven by state-specific factors