The reversed work‐ethic effect: Monkeys avoid stimuli associated with high‐effort1

We investigated how different numbers of responses prior to the presentation of a stimulus influenced preferences for the stimulus in three Japanese monkeys (Macaca fuscata). Monkeys were trained for two kinds of simultaneous discriminations that followed a high‐effort or a low‐effort response. In probe test trials, the stimulus that followed the high‐effort and the stimulus that followed the low‐effort response during discriminations were presented simultaneously. All monkeys chose stimuli that in training followed a low‐effort response. This result suggested that monkeys avoided stimuli that followed high‐effort responses because of the association between those stimuli and the preceding greater effort. The present result is consistent with our previous study conducted with humans, but contradicts analogous studies carried out with pigeons that reported either opposite results (i.e. pigeons preferred the stimuli after high‐effort) or non‐biased preferences. The differences between mammals and birds are discussed in terms of the lack of a successive negative contrast effect in birds.     

Crossmodal spatial attention shift produced by centrally presented gaze cues1

Abstract: Despite previous failures to identify visual‐upon‐auditory spatial‐cuing effects, recent studies have demonstrated that the abrupt onset of a lateralized visual stimulus triggers a shift of spatial attention in response to auditory judgment. Nevertheless, whether a centrally presented visual stimulus orients auditory attention remained unclear. The present study investigated whether centrally presented gaze cues trigger a reflexive shift of attention in response to auditory judgment. Participants fixated on a schematic face in which the eyes looked left or right (the cue). A target sound was then presented to the left or right of the cue. Participants judged the direction of the target as quickly as possible. Even though participants were told that the gaze direction did not predict the direction of the target, the response time was significantly faster when the gaze was in the target direction than when it was in the non‐target direction. These findings provide initial evidence for visual‐upon‐auditory spatial‐cuing effects produced by centrally presented cues, suggesting that a reflexive crossmodal shift of attention does occur with a centrally presented visual stimulus.     

A factor related to the strength of an "Aha!" experience

Abstract: It is natural to assume that the strength of an "Aha!" becomes stronger when an unexpected solution is correct. In this study, this assumption is examined experimentally through a list of possible correct solutions. In the experiment, subjects listed the possible correct solutions before solving the problems, and evaluated the strength of their "Aha!" experience after they solved the problems. It was shown that the strength of the "Aha!" experience was strongest if the correct answer had not been included in the list of possible correct solutions; if included, the strength of the "Aha!" experience corresponded to the answer's position in the list, that is, the later the correct solution listed, the stronger the feeling became. It is suggested that the strength of an "Aha!" experience can be used as an error function in the learning process.     

Attentional shift by eye gaze requires joint attention: Eye gaze cues are unique to shift attention1

Researchers have demonstrated that attentional shift triggered by gaze direction is reflexive. However, here we show that attentional shift by gaze direction was not always reflexive, but could be modulated by another's perspective. In Experiment 1, a schematic face's line of sight to a peripheral target was obstructed by a vertical barrier located between the face and the target under two conditions. However, the line of sight of the face was clear under another two conditions, in which the barrier was located behind the line of sight by utilizing a depth cue. The gaze cue shifted attention only when the line of sight was not blocked (i.e. joint attention was attained). The arrow cue did not shift attention regardless of the obstruction conditions in Experiment 2. These results suggest that attentional shift by gaze cues, but not arrow cues, involve a higher social cognitive process such as interpretation of the gaze.     

Reaction time as an indicator of stimulus‐response binding in affective judgment of visual stimuli1

Conventional studies on affective meanings have been conducted using the semantic differential technique. Although it offers reasonably valid and reliable measures for the bindings between visual stimuli and affective responses, it is dependent on subjective rating. Thus, the present study examined whether the reaction time (RT) of affective judgments for visual stimuli (color, shape, and facial expression) can be an objective indicator of the strength of stimuli‐response bindings. The results can be summarized as follows: (a) RTs for judging Evaluation were longer regardless of stimulus type; (b) RTs for Activity were shorter regardless of stimulus type; and (c) RTs for Lightness and Sharpness depended on stimulus type. These phenomena are consistent with the findings of previous affective meaning studies, suggesting that the RTs for affective judgments can be useful indicators reflecting the strength of the bindings between stimulus properties and affective meanings across various target stimuli and rating scales.     

Effects of verbal working memory and cumulative linguistic knowledge on reading comprehension1

Abstract: In the present study, the effects of verbal working memory (VWM) and cumulative linguistic knowledge (CLK) on reading comprehension were investigated using an individual difference approach. We examined whether VWM and CLK are distinct verbal factors and whether each has independent influences on reading comprehension. VWM was tested using the Japanese Reading Span Test (RST). CLK was assessed using information, vocabulary, and similarity subtests of the Wechsler Adult Intelligence Scale‐Revised (WAIS‐R), as well as with the Hyakurakan kanji reading test. The differences between VWM and CLK were examined using correlation analyses between reading comprehension scores, and digit forward and backward span scores. The results showed that VWM and CLK were independent of each other, and that VWM and CLK independently contributed to reading comprehension. The obtained correlations also showed that CLK was independent of any type of short‐term memory, and that the VWM measured using the RST had little correlation with digit span.