The effect of early visual deprivation on the development of face processing

We evaluated the importance of early visual input for the later development of expertise in face processing by studying 17 patients, aged 10 to 38 years, treated for bilateral congenital cataracts that deprived them of patterned visual input for the first 7 weeks or more after birth. We administered five computerized tasks that required matching faces on the basis of identity (with changed facial expression or head orientation), facial expression, gaze direction and lip reading. Compared to an age–matched control group, patients’ recognition of facial identity was impaired significantly when there was a change in head orientation (e.g. from frontal to tilted up), and tended to be impaired when there was a change in facial expression (e.g. from happy to surprised). Patients performed normally when matching facial expression and direction of gaze (e.g. looking left or right), and in reading lips (e.g. pronouncing ‘u’ or ‘a’). The results indicate that visual input during early infancy is necessary for the normal development of some aspects of face processing, and are consistent with theories postulating the importance of early visual experience (de Schonen & Mathivet, 1989; Johnson & Morton, 1991) and separate neural mediation of different components of face processing (Bruce & Young, 1986).     

The effects of sleep deprivation and incentives on human performance

Summary This study explores whether KR (knowledge of results) and reward compensate for the negative joint effects of sleep deprivation and signal degradation in a choice-reaction task. The negative effect of signal degradation on performance was aggravated by sleep loss and time-on-task, whereas KR improved performance, especially when signals were degraded. Reward changed the effects of time-on-task owing to lack of sleep. Performance was also improved by a brief task interruption after 30 minutes' work, with 5 more minutes to go. These results can be interpreted in terms of the performance model of Sanders (1983), which links energetic mechanisms to stages of information processing. A lack of energetic supply from the arousal mechanism to perceptual processing, induced by signal degradation, sleep deprivation, and time-on-task, was effectively counteracted by KR: KR enables the mobilization of effort to compensate for this lack of arousal. The relation between reward and KR is not yet clear. The interruption effect suggests that the influence of time-on-task is not due to loss of arousal, but causes a reallocation of resources by effort.     

Blindness and social trust: The effect of early visual deprivation on judgments of trustworthiness

Investigating the impact of early visual deprivation on evaluations related to social trust has received little attention to date. This is despite consistent evidence suggesting that early onset blindness may interfere with the normal development of social skills. In this study, we investigated whether early blindness affects judgments of trustworthiness regarding the actions of an agent, with trustworthiness representing the fundamental dimension in the social evaluation. Specifically, we compared performance between a group of early blind individuals with that of sighted controls in their evaluation of trustworthiness of an agent after hearing a pair of two positive or two negative social behaviors (impression formation). Participants then repeated the same evaluation following the presentation of a third (consistent or inconsistent) behavior regarding the same agent (impression updating). Overall, blind individuals tended to give similar evaluations compared to their sighted counterparts. However, they also valued positive behaviors significantly more than sighted controls when forming their impression of an agent’s trustworthiness. Moreover, when inconsistent information was provided, blind individuals were more prone to revise their initial evaluation compared to controls. These results suggest that early visual deprivation may have a dramatic effect on the evaluation of social factors such as trustworthiness.     

The generation effect in monkeys

How well one retains new information depends on how actively it is processed during learning. Active attempts to retrieve information from memory result in more learning than passive observation of the same information (the generation effect). Here, we present evidence for the generation effect in monkeys. Subjects were trained to respond to five-item lists of photographs in a particular order. On some lists, they could request "hints" to guide their behavior; on others, they had to generate the correct order from memory. Training with hints resulted in high levels of initial performance, but accuracy dropped precipitously when the hints were removed on the criterion test. Training without hints led to relatively poor initial performance, but accuracy increased steadily and remained high on the criterion test.     

The moderating effect of motivation on health-related decision-making

Objective: This study identifies how autonomous and controlled motivation moderates the cognitive process that drives the adoption of personalised nutrition services. The cognitive process comprises perceptions of privacy risk, personalisation benefit, and their determinants.

Design: Depending on their level of autonomous and controlled motivation, participants (N = 3453) were assigned to one of four motivational orientations, which resulted in a 2 (low/high autonomous motivation) × 2 (low/high controlled motivation) quasi-experimental design.

Results: High levels of autonomous motivation strengthened the extent to which: (1) the benefits of engaging with a service determined the outcome of a risk-benefit trade-off; (2) the effectiveness of a service determined benefit perceptions. High levels of controlled motivation influenced the extent to which: (1) the risk of privacy loss determined the outcome of a risk-benefit trade-off; (2) controlling personal information after disclosure and perceiving the disclosed personal information as sensitive determined the risk of potential privacy loss.

Conclusion: To encourage the adoption of personalised dietary recommendations, for individuals with high levels of autonomous motivation emphasis should be on benefits and its determinants. For those with high levels of controlled motivation, it is important to focus on risk-related issues such as information sensitivity.     

Parametric exploration of the Simon effect across visual space.

The Simon effect refers to the performance advantage for responding to the nonspatial identity of the target when the target's irrelevant location corresponds with the relative location of the response. The present study is a parametric examination of the magnitude of the Simon effect across visual space. Response keys were arranged along vertical, horizontal, and two diagonal axes, and stimuli were arranged in two concentric circles (near and far from fixation) along the same axes. The results show that the Simon effect is of similar magnitude regardless of stimulus-response axis. In contrast to findings from stimulus-response compatibility paradigms, there was no evidence in this study for the presence of an orthogonal compatibility effect or left-right prevalence effect, suggesting that these effects only arise when response location is relevant. The results demonstrate the robust generalizability of the Simon effect under different spatial conditions and thus broaden the relevance of the Simon effect to a variety of applications.     

Motivational incentives modulate age differences in visual perception

This study examined whether motivational incentives modulate age-related perceptual deficits. Younger and older adults performed a perceptual discrimination task in which bicolored stimuli had to be classified according to their dominating color. The valent color was associated with either a positive or negative payoff, whereas the neutral color was not associated with a payoff. Effects of incentives on perceptual efficiency and response bias were estimated using the diffusion model (Ratcliff, 1978). Perception of neutral stimuli showed age-related decline, whereas perception of valent stimuli, both positive and negative, showed no age difference. This finding is interpreted in terms of preserved top-down control over the allocation of perceptual processing resources in healthy aging.     

The effect of monetary incentives on backward digit span performance

In order to determine if monetary-incentive effects, particularly the detrimental effects of such incentives on human learning and performance, might be mediated by anxiety, 52 college students were administered six backward digit trials in a preexperimental, baseline phase and six trials in an experimental, test phase. Of the 52 subjects, 26 were paid 50 cents following each correct recitation of a backward digit series during the test phase. The remaining 26 were unpaid control subjects. Results showed that the rationale for the study was correct because state anxiety was indeed negatively related to backward digit span performance as previous research had shown, but the offer of reward did not elevate state anxiety scores and, more importantly, the offer of reward led to a significant improvement in backward digit span performance—an effect which is the opposite of what would be predicted by the anxiety hypothesis. The reward effects of theoretical interest in planning this research were those facilitating and detrimental effects that are produced by offering elementary, high school, or college students small amounts of money (typically from $1 to $3) as a superfluous inducement to participate in a study of human learning or performance. The results of this study discredit any explanation of such reward effects which attributes the effects to reward-induced anxiety.     

The effect of motivation and word characteristics on recognition

Two tachistoscopic studies assessed the effects of motivation on high-speed word processing. Study 1 assessed the effect of anxiety and Study 2 the effect of hunger compared to satiation. Words differed in interletter associative frequency (generated value), Thorndike-Lorge word frequency, and categories. In both studies, all three word variables yielded significant main effects. Motivational relevance of words did not significantly alter word recognition, the food words being most readily recognized and negatively emotional words least readily recognized in both studies. Anxiety did not have a significant effect, but hunger in interaction with word characteristics was found to be facilitating. Contrary to Hullian theory regarding word dominance and drive interaction and to Broadbent's "filtering" hypothesis, hunger in comparison to satiation increasingly facilitated word recognition the more infrequent the words and the more rare were the interletter associations.