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The physiological blind spot corresponds to the optic disc where the retina contains no light-detecting photoreceptor cells. Our perception seemingly fills in this gap in input. Here we suggest that rather than an active process, such perceptual filling-in could instead be a consequence of the integration of visual inputs at higher stages of processing discounting the local absence of retinal input. Using functional brain imaging, we resolved the retinotopic representation of the physiological blind spot in early human visual cortex and measured responses while participants perceived filling-in. Responses in early visual areas simply reflected the absence of visual input. In contrast, higher extrastriate regions responded more to stimuli in the eye containing the blind spot than the fellow eye. However, this signature was independent of filling-in. We argue that these findings agree with philosophical accounts that posit that the concept of filling-in of absent retinal input is unnecessary.

Study on how the visual brain groups fragmented stimuli into coherent shapes & the role of stimulus awareness.

Recent research suggests superior performance with sports movements, such as shooting and golf-putting, for targets surrounded by small shapes (leading to a perceptually larger target), compared to large shapes (perceptually smaller target). One explanation is that these effects are driven by the Ebbinghaus illusion modulating perceived target size. Here we examine this assumption with a digital shooting game where participants aimed a ‘laser gun’ towards a target. We manipulated perceived target size either with a Ebbinghaus-style surround or changing physical target size. Aiming performance was noticeably worse with large Ebbinghaus surround. However, changing physical target size did not affect performance, suggesting these effects were driven by the presence of the surround rather perceived target size per se. Individual illusion magnitude was also uncorrelated with aiming performance. Further experiments demonstrated that interference of target perception by the surround (visual crowding) instead explains altered performance. Our results should motivate reinterpretations of previous studies purporting an effect of perceived size without controlling for the confounding contextual effects.

The Ebbinghaus and Delboeuf illusions affect the perceived size of a target circle depending on the size and proximity of circular inducers or a ring. Converging evidence suggests that these illusions are driven by interactions between contours mediated by their cortical distance in primary visual cortex. We tested the effect of cortical distance on these illusions using two methods: First, we manipulated retinal distance between target and inducers in a two-interval forced choice design, finding that targets appeared larger with a closer surround. Next, we predicted that targets presented peripherally should appear larger due to cortical magnification. Hence, we tested the illusion strength when positioning the stimuli at various eccentricities, with results supporting this hypothesis. We calculated estimated cortical distances between illusion elements in each experiment and used these estimates to compare the relationship between cortical distance and illusion strength across our experiments. In a final experiment, we modified the Delboeuf illusion to test whether the influence of the inducers/annuli in this illusion is influenced by an inhibitory surround. We found evidence that an additional outer ring makes targets appear smaller compared to a single-ring condition, suggesting that near and distal contours have antagonistic effects on perceived target size.

The dialects theory of cross-cultural communication suggests that due to culture-specific characteristics in the expression of emotion, we can recognise own-culture emotional expressions more accurately than other-culture emotional expressions. This effect is suggested to occur due to the nonconvergent social evolution that takes place in different geographical regions. Based on the evolutionary value of own-culture social signals, previous research has suggested that own-culture emotional expressions can be appraised without conscious awareness. The current study tested this hypothesis. We developed, validated, and made open access what is to our knowledge the first labelled, multicultural facial stimuli set, including freely expressed and Facial Action Coding System instructed emotional expressions. We assessed emotional recognition and cultural familiarity responses during brief backward-masked presentations in British participants. We found that emotional recognition and cultural familiarity were higher for own-culture faces. A Bayesian analysis of face-detection and emotional-recognition performance revealed that faces were not processed subliminally. Further analysis of awareness, using hits (correct detection/recognition) and misses (incorrect detection/recognition), showed that face-detection hits were a necessary condition for reporting higher familiarity for own-culture faces. These findings suggest that the own-culture emotional recognition advantage is preserved under conditions of backwards masking and that the appraisal of cultural familiarity involves conscious awareness.

While there is a global shift towards smaller families, some groups maintain relatively high fertility rates. The 2013 New Zealand census data were used to investigate the nature of fertility between ethnicities in New Zealand. The NZ Deprivation Index 2013 was used as a measure of socioeconomic status to determine the relationships with fertility. The results mirror research outside of New Zealand in that socioeconomic status is inversely correlated to fertility. Using crude average fertility rates, sole-ethnicity Pasifika and Māori ethnic groups still have substantially higher fertility than sole-ethnicity Europeans and Asians ethnic groups, even when simultaneously accounting for age, socioeconomic status, education, and religious affiliation. Christians have more children than individuals reportedly without any religion, and fertility rates drop on average for mothers who have higher formal qualifications. Our findings suggest that cultural, or other ethnic-specific factors differentially affe...

Common brain areas play a role in processing both personality and odor, while personality theory predicts that olfactory performance should vary according to personality traits. The Big Five model of personality is considered a gold standard measure but has yet to be directly applied in investigations linking personality and olfactory responses. Moreover, olfactory measures commonly used in personality studies are usually rudimentary sensory performance indices such as thresholds as opposed to higher-order perceptual and psychological metrics. This cross-sectional study examined the relationship between comprehensive measures of personality and perceptual responses to odors. Personality was measured using a comprehensive test of the Big Five model of personality, while olfactory responses included identification, pleasantness, perceived intensity, and familiarity. Odors were presented using the Sniffin’ Sticks test. Small to moderate correlations were noted between aspects of personality and response to odor, even after controlling for participant (N = 74) characteristics such as age and gender. Regression analyses indicated that, overall, odor familiarity co-varies the most with aspects of personality. Responses to olfactory stimuli are moderated by specific personality dimensions. This finding is consistent with approach and avoidance motivational models of personality.

Pacific people living in New Zealand are less likely to participate in gambling activities than the general population but those who do gamble are at greater risk of being problem gamblers. This difference remains when socio-economic variables are controlled for. To date, little research has investigated the reasons underlying these differences. The present exploratory study investigated Pacific people's thoughts about gambling through a series of focus groups involving 97 participants, including Pacific gamblers, non-gamblers, gambling venue workers, gambling treatment providers and church leaders. The results suggest that some Pacific people draw a distinction between ‘community’ and ‘commercial’ types of gambling, that gambling is understood by some to be an easy way in which to make money, and also that familial and church obligations can motivate gambling behaviour. These findings inform possible unique features of gambling in Pacific cultures in New Zealand and internationally. Moreover, together wi...

Hulleman & Olivers (H&O) argue that the primary unit in search should be fixations, and in doing so posit a Functional View Field (FVF). There is evidence from the object-based visual attention literature that the FVF may not process visual information uniformly. Here I sketch how object-based attention may influence processing within the FVF as well as the shape of the FVF.