The effects of empathy on search efforts for missing persons

People have difficulty sighting missing persons, partially because people's limited cognitive resources are required for searching. As a result, people sometimes do not devote resources to searching. This research will examine whether empathy increases the resources devoted to searching and search performance. In Experiment 1, we will manipulate empathy toward a formerly missing person and measure willingness to volunteer to search and actual search performance. In Experiment 2, we will manipulate empathy felt toward a missing person. We will measure the time participants spend studying the missing person's photograph. We hypothesize that participants induced to feel empathy will indicate more willingness to search (Exp 1 & 2), put more effort toward searching (Exp 1), and spend more time studying the photograph (Exp 2) than those not induced to feel empathy. If empathy increases search effort and performance, it could be induced in actual missing persons cases to increase recovery rates.     

Two‐year‐olds use adults' but not peers' points

In the current study, 24‐ to 27‐month‐old children (N = 37) used pointing gestures in a cooperative object choice task with either peer or adult partners. When indicating the location of a hidden toy, children pointed equally accurately for adult and peer partners but more often for adult partners. When choosing from one of three hiding places, children used adults’ pointing to find a hidden toy significantly more often than they used peers’. In interaction with peers, children's choice behavior was at chance level. These results suggest that toddlers ascribe informative value to adults’ but not peers’ pointing gestures, and highlight the role of children's social expectations in their communicative development.     

Early contributions to infants’ mental rotation abilities

Some cognitive abilities exhibit reliable gender differences, with females outperforming males in specific aspects of verbal ability, and males showing an advantage on certain spatial tasks. Among these cognitive gender differences, differences in mental rotation are the most robust, and appear to be present even in infants. A large body of animal research suggests that gonadal hormones, particularly testosterone, during early development could contribute to this gender difference in mental rotation. Also, substantial evidence supports an influence of socialization on mental rotation performance. The present study investigated the relationship of two types of factors, early postnatal testosterone exposure and parental attitudes about gender, to mental rotation performance in 61 healthy infants (29 males, 32 females). We measured salivary testosterone at two time points: 1–2.5 months of age and 5–6 months of age. Infants’ mental rotation performance and parents’ attitudes about gender were assessed at 5–6 months of age. As predicted, testosterone concentrations were significantly higher in boys than girls in early infancy (d = 0.54), and boys performed significantly better than girls on mental rotation (d = 0.64). A significant positive correlation between testosterone at age 1–2.5 months and mental rotation was found only in boys (r = 0.50, p = .01). A significant negative correlation between parents’ gender‐stereotypical attitudes and mental rotation performance was found only in girls (r = ?.57, p = .002). These findings suggest that the early postnatal testosterone surge (also known as “mini‐puberty”) may have organizational influences on mental rotation performance in boys, and that parents may influence their daughters’ mental rotation abilities beginning very early in life.     

Human ostensive signals do not enhance gaze following in chimpanzees,but do enhance object-oriented attention

The previous studies have shown that human infants and domestic dogs follow the gaze of a human agent only when the agent has addressed them ostensively—e.g., by making eye contact, or calling their name. This evidence is interpreted as showing that they expect ostensive signals to precede referential information. The present study tested chimpanzees, one of the closest relatives to humans, in a series of eye-tracking experiments using an experimental design adapted from these previous studies. In the ostension conditions, a human actor made eye contact, called the participant’s name, and then looked at one of two objects. In the control conditions, a salient cue, which differed in each experiment (a colorful object, the actor’s nodding, or an eating action), attracted participants’ attention to the actor’s face, and then the actor looked at the object. Overall, chimpanzees followed the actor’s gaze to the cued object in both ostension and control conditions, and the ostensive signals did not enhance gaze following more than the control attention-getters. However, the ostensive signals enhanced subsequent attention to both target and distractor objects (but not to the actor’s face) more strongly than the control attention-getters—especially in the chimpanzees who had a close relationship with human caregivers. We interpret this as showing that chimpanzees have a simple form of communicative expectations on the basis of ostensive signals, but unlike human infants and dogs, they do not subsequently use the experimenter’s gaze to infer the intended referent. These results may reflect a limitation of non-domesticated species for interpreting humans’ ostensive signals in inter-species communication.     

Practice reduces set-specific capture costs only superficially

Contingent attentional capture costs are doubled or tripled under certain conditions when multiple attentional sets guide visual search (e.g., “search for green letters” and “search for orange letters”). Such “set-specific” capture occurs when a potential target that matches one attentional set (e.g., a green stimulus) impairs the ability to identify a temporally proximal target that matches another attentional set (e.g., an orange stimulus). In the present study, we examined whether these severe set-specific capture effects could be attenuated through training. In Experiment 1, half of participants experienced training consisting of mostly trials involving a set switch from distractor to target, while the other half experienced training consisting of mostly trials in which a set switch was not required. Upon test, participants trained on set switches produced greatly reduced set-specific capture effects compared to their own pretraining levels and compared to participants trained on trials without a set switch. However, in Experiments 2 and 3, we found that these training effects did not transfer to a new color context or even a single new target color, indicating that they were specific and involved low-level associative learning. We concluded that set-specific capture is pervasive and largely immutable, even with practice.