Multi-stage mental process for economic choice in capuchins

We studied economic choice behavior in capuchin monkeys by offering them to choose between two different foods available in variable amounts. When monkeys selected between familiar foods, their choice patterns were well-described in terms of relative value of the two foods. A leading view in economics and biology is that such behavior results from stimulus-response associations acquired through experience. According to this view, values are not psychologically real; they can only be defined a posteriori. One prediction of this associative model is that animals faced for the first time with a new pair of foods learn to choose between them gradually. We tested this prediction. Surprisingly, we find that monkeys choose as effectively between new pairs of foods as they choose between familiar pairs of foods. We therefore, propose a cognitive model in which economic choice results from a two-stage mental process of value-assignment and decision-making. In a follow-up experiment, we find that the relative value assigned to three foods in sessions in which we tested them against each other combine according to transitivity.     

Effects of instruction on learners’ ability to generate an effective pathway in the method of loci

One of the most effective mnemonic techniques is the well-known method of loci. Learning and retention, especially of sequentially ordered information, is facilitated by this technique which involves mentally combining salient loci on a well-known path with the material to be learned. There are several variants of this technique that differ in the kind of path that is suggested to the user and it is implicitly assumed that these variants are comparable in effectiveness. The experiments reported in this study were designed to test this assumption. The data of two experiments show that participants who are instructed to generate and apply loci on a route to their work recall significantly more items in a memory test than participants who are instructed to generate and apply loci on a route in their house. These results have practical implications for the instruction and application of the method of loci.     

Predicting first intercourse among urban early adolescent girls: The role of emotions

Little is known about how girls perceive their ongoing or future sexual experiences, especially the emotions that they associate with these experiences. This study examined how early adolescent girls characterise first intercourse experiences in terms of positive and negative emotions over a one-year period. A US sample of 162 girls (12–14 years), primarily Latina and Black, completed two interviews one year apart that assessed sexual cognitions, affect, and behaviour. Girls anticipated primarily negative emotions associated with first intercourse, but recalled primarily positive emotions for first and recent intercourse experiences. In addition, girls’ emotion scores proved more useful than two types of cognitions (intentions and perceived readiness) and pre-intercourse sexual experience in predicting transitions to intercourse over the one-year period.     

One, two, three, four, or is there something more? Numerical discrimination in day-old domestic chicks

Human adults master sophisticated, abstract numerical calculations that are mostly based on symbolic language and thus inimitably human. Humans may nonetheless share a subset of non-verbal numerical skills, available soon after birth and considered the evolutionary foundation of more complex numerical reasoning, with other animals. These skills are thought to be based on the two systems: the object file system which processes small values (<3) and the analogue magnitude system which processes large magnitudes (>4). Infants’ ability to discriminate 1 vs. 2, 1 vs. 3, 2 vs. 3, but not 1 vs. 4, seems to indicate that the two systems are independent, implying that the conception of a continuous number processing system is based on precursors that appear to be interrupted at or about the number four. The findings from the study being presented here indicating that chicks are able to make a series of discriminations regarding that borderline number (1 vs. 4, 1 vs. 5, 2 vs. 4) support the hypothesis that there is continuity in the number system which processes both small and large numerousness.     

Porn,Peers, and Performing Oral Sex: The Mediating Role of Peer Norms on Pornography’s Influence Regarding Oral Sex

ABSTRACT

The goal of this study was to offer insights into how pornography use might be linked to young adults’ sexual experiences via the mediating role of peer norms (i.e., their perceptions of what same-sex peers do sexually). We focused on oral sex behavior, as it is common in pornography and among young people. Young adults (N = 349; ages 19–30; 54% female) were recruited through a crowdsourcing website. Participants completed an anonymous online survey about the frequency that they observed various sexual behaviors in online pornography, the frequency that they engaged in these behaviors, and their perceptions of the frequency that their peers engaged in these behaviors. Frequency of viewing cunnilingus (men) or fellatio (women) in pornography predicted how often they engaged in oral sex, and this association was mediated by their perceptions of how frequently their peers engaged in oral sex. Peer norms did not mediate how frequently they received oral sex. Findings are discussed in terms of implications for understanding how pornography may relate to young people’s social norms surrounding oral sex and their performance of sexual behaviors, as well as for understanding generally how media consumption relates to adoption of media behaviors through suggesting a social norm.     

Phonological and working memory mechanisms involved in written spelling

Recent theories of spelling based on neuropsychological data and on computational modelling (Caramazza & Miceli, 1990; Caramazza, Miceli, Villa, & Romani, 1987; Glasspool & Houghton, 2005; Glasspool, Shallice, & Cipolotti, 2006; Miceli & Capasso, 2006; Rapp & Kong, 2002) assume that a working memory system is used to store identity and order of the graphemes, and propose that an impairment of this system, called Graphemic Buffer (GB), is marked by the presence of a number of typical effects. Recently, this disorder has been simulated by different versions of the Competitive Queuing model (Glasspool & Houghton, 2005; Glasspool et al., 2006). The effect of the disruption of this mechanism in written spelling was investigated by means of a dual task in the present study. Three-syllable and four-syllable words were presented to normal adults for aural presentation (Experiment 1) and spelling by copying (Experiment 2). In order to investigate the effects of dual tasks, and the possible involvement of phonological codes, three conditions were used: simple dictation, concurrent articulation, and foot tapping. The results showed strong effects of concurrent articulation, and were consistent with the hypothesis that this task disrupted the serial operations of readout and sequential planning of the GB. They were also consistent with the simulations of the Competitive Queuing model, suggesting possible loci of the effects.     

The relative lability of mobile and stationary components in a visual-motor adaptation task

The results of previous studies of intermanual transfer of prism adaptation may have been biased because the arm was mobile during training, rather than for instance the head. It was hypothesized that adaptation will be more associated with a joint when it is mobile rather than stationary. Intermanual transfer when arm was mobile and head stationary was compared with that when head was mobile and arm stationary. Also measured was the adaptation persisting when the mobile part in training was stationary in testing. The results showed, against the original hypothesis, that adaptation tends to be associated with a stationary joint. This fits in with evidence that there is greater position uncertainty in a stationary joint and that this is associated with adaptability.