Keiko Ihaya

Can you eat it? A link between categorization difficulty and food likability

In the present study we examined whether categorization difficulty regarding a food is related to its likability. For this purpose, we produced stimulus images by morphing photographs of a tomato and a strawberry. Subjects categorized these images as either a tomato or a strawberry and in separate sessions evaluated the food’s eatability or the subject’s willingness to eat (Experiments 1 and 2) and the likeliness of existence of each food (Experiment 2). The lowest score for ca- tegorization confidence coincided with the lowest scores for eatability, willingness to eat, and likeliness of existence. In Experiment 3, we found that food neophobia, a trait of ingestion avoidance of novel foods, modulated food likability but not categorization confidence. These findings suggest that a high categorization difficulty generally co-occurs with a decrease in food likability and that food neophobia modulates likability. This avoidance of difficult-to-categorize foods seems ecologically valid because before eating we have little information regarding whether a food is potentially harmful.

Narcissistic People Cannot Be Moved Easily by Visual Stimulation

We examined the relationship between personality and visually induced self-motion perception (latency, duration, and magnitude). A psychological experiment with radially expanding patterns that induced self-motion perception along the fore and aft axis was conducted, followed by personality assessments. We found that all the measures of self-motion perception we examined correlated negatively with the degree of narcissistic traits.

When categorization-based stranger avoidance explains the uncanny valley: A comment on MacDorman and Chattopadhyay (2016)

Artificial objects often subjectively look eerie when their appearance to some extent resembles a human, which is known as the uncanny valley phenomenon. From a cognitive psychology perspective, several explanations of the phenomenon have been put forth, two of which are object categorization and realism inconsistency. Recently, MacDorman and Chattopadhyay (2016) reported experimental data as evidence in support of the latter. In our estimation, however, their results are still consistent with categorization-based stranger avoidance. In this Discussions paper, we try to describe why categorization-based stranger avoidance remains a viable explanation, despite the evidence of MacDorman and Chattopadhyay, and how it offers a more inclusive explanation of the impression of eeriness in the uncanny valley phenomenon.

Più mosso: Fast self-motion makes cyclic action faster in virtual reality

Visually induced self-motion (vection) affects the speed at which actions are performed. However, it has been unclear whether this speedy action induced by vection is based on the modulation of mental tempo. To clarify this issue, we tested whether the speed of vection influenced an observers cyclic action related to mental tempo. Observers viewed fast and slow moving optic flow stimuli and dynamic random dots, whilst handclapping at their preferred tempo. The results revealed that the clapping rate was the fastest in the fastest optic flow condition. This effect vanished when optic flow stimuli moved fast but did not induce vection. Fast optic flow stimuli also induced larger pupil dilation, suggesting that it increased the observers arousal level. These results suggest that illusory self-motion increased arousal levels, thereby modulating mental tempo.

Avoidance of novelty contributes to the uncanny valley

A hypothesis suggests that objects with a high degree of visual similarity to real humans trigger negative impressions (i.e., the uncanny valley). Previous studies have suggested that difficulty in object categorization elicits negative emotional reactions to enable the avoidance of potential threats. The present study further investigated this categorization-difficulty hypothesis. In an experiment, observers categorized morphed images of photographs and human doll faces as “photograph” or “doll” and evaluated the perceived eeriness of the images. Additionally, we asked the observers to answer questionnaires on behavioral inhibition systems (BIS). The results indicated that individual differences in the BIS score were associated with enhanced eeriness in the objects with a specific human likeness. These findings suggest that the tendency to avoid a potentially threatening novel experience contributes to promoting the perceived eeriness of objects with some degree of visual similarity to real humans.

Extrinsic Motivation Underlies Precise Temporal Production

The present study examined the effect of extrinsic motivation on temporal interval production. Observers were asked to produce the duration of 2.5 sec as accurately as possible, and gained or lost a certain amount of score after each trial. The amount of provided scores varied with the color of target: red or green circle was assigned to high or low scores. We found that the higher amount of expected gain and loss decreased the absolute error of temporal production. However, no effect of motivation was found on the constant error and variable error. These results suggest that extrinsic motivation improved the precision of temporal production. We propose that the striatal dopamine system may mediate motivational influences on time perception.