How pigeons discriminate the relative frequency of events.

This study examined how pigeons discriminate the relative frequencies of events when the events occur serially. In a discrete-trials procedure, 6 pigeons were shown one light nf times and then another nl times. Next, they received food for choosing the light that had occurred the least number of times during the sample. At issue were (a) how the discrimination was related to two variables, the difference between the frequencies of the two lights, D = nf - nl, and the total number of lights in the sample, T = nf + nl; and (b) whether a simple mathematical model of the discrimination process could account for the data. In contrast with models that assume that pigeons count the stimulus lights, engage in mental arithmetic on numerons, or remember the number of stimuli, the present model assumed only that the influence of a sample stimulus on choice increases linearly when the stimulus is presented, but decays exponentially when the stimulus is absent. The results showed that, overall, the pigeons discriminated the relative frequencies well. Their accuracy always increased with the absolute value of the difference D and, for D > 0, it decreased with T. Performance also showed clear recency, primacy, and contextual effects. The model accounted well for the major trends in the data.     

Power and Psychological Well-Being in Late Adolescent Romantic Relationships

Using Olsen and Cromwell's (1975) three facetsof interpersonal power (power in resources, process, andoutcomes), we examined the balance of power in lateadolescent romantic relationships and the associations between interpersonal power, adolescents'self-esteem, and depression. Participants were 61adolescent couples who were primarily European-American(90% of girls and 93% of boys), with the remainder being comprised of approximately 2-3% each of NativeAmerican, Asian, African American, and Hispanicindividuals. We assessed power in terms of access toemotional resources, control during video-tapedinteraction, and control over decision-making. Overall,couples were more likely to be described by themselvesand by independent observers as egalitarian, with themajority of couples equally contributing emotional resources, sharing power in interaction, andsharing decision-making responsibility. However,romantic relationships characterized by inequality inthe contribution of emotional resources and indecisionmaking were associated with greater psychologicalsymptomatology, especially for females.     

Developing a Cultural Theory of Mind: The CIAO Approach

The study of children's knowledge about minds is an extremely active area of developmental psychology. This article discusses the reach of this research and the theoretical views guiding it. It then presents some cultural variations (within the United States) in behavior explanation and explains the relevance of that variation to developmental theory. A theory ofearly mind reading that is presented incorporates culture, introspection, analogy, and ontogeny (CIAO).     

Lion Kings or puppies: the influence of fantasy on children’s understanding of pretense

Many have thought that children have an early appreciation of the mind in the case of pretend play. Results from several experiments are against this. However, an experiment by Lillard (Body or mind: children’s categorizing of pretense, Child Development, 67 (1996), 1717-1734, Experiment 4) suggested that when a pretense is about a fantasy character, instead of a real entity, children might have a better understanding of the mind’s involvement. The present experiment tested this, and found that indeed, when pretending to be a fantasy character is at issue, 4-year-olds are significantly more apt to indicate the mind’s involvement. Several possible reasons for this result are discussed.     

The role of semantically related distractors during encoding and retrieval of words in long-term memory

We examined the influence of divided attention (DA) on recognition of words when the concurrent task was semantically related or unrelated to the to-be-recognised target words. Participants were asked to either study or retrieve a target list of semantically related words while simultaneously making semantic decisions (i.e., size judgements) to another set of related or unrelated words heard concurrently. We manipulated semantic relatedness of distractor to target words, and whether DA occurred during the encoding or retrieval phase of memory. Recognition accuracy was significantly diminished relative to full attention, following DA conditions at encoding, regardless of relatedness of distractors to study words. However, response times (RTs) were slower with related compared to unrelated distractors. Similarly, under DA at retrieval, recognition RTs were slower when distractors were semantically related than unrelated to target words. Unlike the effect from DA at encoding, recognition accuracy was worse under DA at retrieval when the distractors were related compared to unrelated to the target words. Results suggest that availability of general attentional resources is critical for successful encoding, whereas successful retrieval is particularly reliant on access to a semantic code, making it sensitive to related distractors under DA conditions.     

Sensing the presence of the deceased: A narrative review

Researchers have reported that bereaved people often continue to sense the presence of the deceased. A particular collection of such experiences can be identified as instilling a perception that the deceased person is in some manner present in the company of the bereaved person. The aim of the current review was to synthesise the results on this topic to provide a comprehensive over-view for practitioners working with bereaved people who report these experiences. The studies were reviewed in terms of the nature of the experiences described, the provision of explanatory models to understand the significance of these experiences, describing any culturally specific aspects of these experiences, discussion of the personal impact of having the experiences, and for recommendations of how people who have these experiences can be supported.     

Play on: Retrospective Reports of the Persistence of Pretend Play Into Middle Childhood

Piaget (1962) asserted that children stop engaging in pretend play when they enter the concrete operational stage because they become able to accommodate reality and no longer need to assimilate it to their wishes. Consistent also with the views of Vygotsky, discussion of pretend play in developmental psychology is typically confined to early childhood, yet the activity itself does not seem to be so confined. As a preliminary investigation of pretend play in middle childhood, undergraduates were asked to complete a retrospective questionnaire about their childhood pretend play. The questionnaire items queried them about the content and context of their prior pretense engagements, when and why they stopped pretending, and personality characteristics relevant to pretense and fantasy. On average, respondents reported ceasing to pretend around 11 years of age. Among the statistically significant predictors of participants’ reported ages of ceasing to pretend were gender, childhood environs, siblings’ ages, belief in fantastical entities as a child, and participants involved in the last pretend memory. This preliminary study lays a foundation for future studies exploring the role of pretending in middle childhood. Although this study suggests that pretending is still widespread in middle childhood, it sheds no light on its function. This is an important issue across all ages that future research should address.