Means-means-end tool choice in cotton-top tamarins (Saguinus oedipus): finding the limits on primates’ knowledge of tools

Most studies of animal tool use require subjects to use one object to gain access to a food reward. In many real world situations, however, animals perform more than one action in sequence to achieve their goals. Of theoretical interest is whether animals have the cognitive capacity to recognize the relationship between consecutive action sequences in which there may be one overall goal and several subgoals. Here we ask if cotton-top tamarins, a species that in captivity uses tools to solve means-end problems, can go one step further and use a sequence of tools (means) to obtain food (end). We first trained subjects to use a pulling tool to obtain a food reward. After this initial training, subjects were presented with problems in which one tool had to be used in combination with a second in order to obtain food. Subjects showed great difficulty when two tools were required to obtain the food reward. Although subjects attended to the connection between the tool and food reward, they ignored the physical connection between the two tools. After training on a two-tool problem, we presented subjects with a series of transfer tests to explore if they would generalize to new types of connections between the tools. Subjects readily transferred to new connections. Our results therefore provide the first evidence to date that tamarins can learn to solve problems involving two tools, but that they do so only with sufficient training.     

Bidirectional Effects of Positive Affect,Warmth, and Interactions Between Mothers With and Without Symptoms of Depression and Their Toddlers

Maternal depression has negative implications for parenting and child outcomes, but it is also important to understand the daily transactional interactions that occur between mothers varying in symptoms of depression and their children. The current study aimed to examine immediate bidirectional effects between maternal warmth and positive affect and toddler affect in a sample of mothers varying in symptoms of depression. Ninety-one mothers and their 24-month-old toddlers completed a laboratory free-play/clean-up task. Mothers rated their symptoms of depression using the CES-D, and maternal warmth and positive affect and toddler positive and negative affect were observationally coded from a free-play and clean-up laboratory task. Sequential analyses indicated that mothers with no or mild symptoms of depression exhibited mutual positive affect with their children, but mothers with more severe symptoms of depression did not. Mothers with higher symptoms of depression displayed a decrease in warmth concurrent with toddlers’ positive affect. Further, unlike dyads in which mothers had higher symptoms of depression, dyads of mothers with lower symptoms appeared to exhibit some covariation in positive affect across the episode. These results provide evidence that even in non-clinical samples, affective manifestations of mothers’ subthreshold levels of depression may have negative immediate effects on toddlers’ emotions, and that mothers without symptoms of depression may have more reciprocal affective exchanges with their toddlers.     

Self-esteem differences in the effects of hypocrisy induction on behavioral intentions in the health domain

Two studies investigated whether individuals with varying levels of self-esteem respond differently in the hypocrisy paradigm. In the first study, all participants were regular smokers. Those in the hypocrisy condition delivered a speech in front of a camera on the dangers of smoking. The principal dependent measure was the intention to stop smoking. In the second study, participants in the hypocrisy condition wrote a public (personally identifiable) passage about the importance of a healthy lifestyle. The principal dependent measure was the intention to improve one's health behaviors. In both studies, self-esteem scores were positively related to intentions to change behavior in the hypocrisy condition but not in a control condition. The implications of these findings for conceptions of self-esteem and for dissonance theory are discussed.     

The nature of phoneme representation in spoken word recognition

Four experiments used the psychological refractory period logic to examine whether integration of multiple sources of phonemic information has a decisional locus. All experiments made use of a dual-task paradigm in which participants made forced-choice color categorization (Task 1) and phoneme categorization (Task 2) decisions at varying stimulus onset asynchronies. In Experiment 1, Task 2 difficulty was manipulated using words containing matching or mismatching coarticulatory cues to the final consonant. The results showed that difficulty and onset asynchrony combined in an underadditive way, suggesting that the phonemic mismatch was resolved prior to a central decisional bottleneck. Similar results were found in Experiment 2 using nonwords. In Experiment 3, the manipulation of task difficulty involved lexical status, which once again revealed an underadditive pattern of response times. Finally, Experiment 4 compared this prebottleneck variable with a decisional variable: response key bias. The latter showed an additive pattern of responses. The experiments show that resolution of phonemic ambiguity can take advantage of cognitive slack time at short asynchronies, indicating that phonemic integration takes place at a relatively early stage of spoken word recognition.     

For Better and Worse: Social Influences on Coronary Heart Disease Risk

From the neighborhoods we live in to those we marry, other people are a part of our everyday lives. Mounting evidence suggests that these social factors constitute risk and resilience influences for coronary heart disease (CHD). The current aim is to summarize the literature into four representative categories relating to CHD risk: social environments, social roles, social resources, and close relationships. The argument is made that these factors moderate and mediate stress and associated physiological responses constituting a psychosomatic pathway to disease.     

Interactions of reading and semantics along the ventral visual processing stream

Converging evidence supports a distributed-plus-hub view of semantic processing, in which there are distributed modular semantic sub-systems (e.g., for shape, colour, and action) connected to an amodal semantic hub. Furthermore, object semantic processing of colour and shape, and lexical reading and identification, are processed mainly along the ventral stream, while action semantic processing occurs mainly along the dorsal stream. In Experiment 1, participants read a prime word that required imagining either the object or action referent, and then named a lexical word target. In Experiments 2 and 3, participants performed a lexical decision task (LDT) with the same targets as in Experiment 1, in the presence of foils that were legal nonwords (NW; Experiment 2) or pseudohomophones (PH; Experiment 3). Semantic priming was similar in effect size regardless of prime type for naming, but was greater for object primes than action primes for the LDT with PH foils, suggesting a shared-stream advantage when the task demands focus on orthographic lexical processing. These experiments extend the distributed-plus-hub model, and provide a novel paradigm for further research.     

“Know Whence you Came”: Psychoanalytic Theory,Queer Theory,and the Mixed-Race Experience

Deeply rooted U.S. cultural practices and legislative processes have facilitated the dissociation, erasure, and evasion of engagement with mixed-race subjectivities. As multiracial clinicians, we attempt to reexamine the discourse around race in psychoanalytic literature, questioning the process by which dominant monoracial norms have been constructed, reproduced, and codified as normal and acceptable. We propose that the absence of multiracial subjectivities from the psychoanalytic literature reflects a broader social discomfort with and cultural dissociation of the mixed-race experience. We further suggest that it is necessary to engage both analytically and queer-ly with the subjective experience of racial multiplicity—positing that multiracial subjectivities might best be understood as subjectivities that are “racially queer.”     

Ethical and Regulatory Considerations for Using Social Media Platforms to Locate and Track Research Participants

As social media becomes increasingly popular, human subjects researchers are able to use these platforms to locate, track, and communicate with study participants, thereby increasing participant retention and the generalizability and validity of research. The use of social media; however, raises novel ethical and regulatory issues that have received limited attention in the literature and federal regulations. We review research ethics and regulations and outline the implications for maintaining participant privacy, respecting participant autonomy, and promoting researcher transparency when using social media to locate and track participants. We offer a rubric that can be used in future studies to determine ethical and regulation-consistent use of social media platforms and illustrate the rubric using our study team’s experience with Facebook. We also offer recommendations for both researchers and institutional review boards that emphasize the importance of well-described procedures for social media use as part of informed consent.     

The Ethnic Adornment Survey (EAS): Measuring Individuals’ Use of Clothing to Express Ethnic Identity

The present paper introduces the Ethnic Adornment Survey as a measure of the relative frequency with which individuals use clothing to express their ethnic identity. Results of exploratory factor analyses in a pilot study (n = 174) and confirmatory factor analyses in a main study (n = 217) revealed that the Ethnic Adornment Survey measures two positively correlated, yet distinct, ethnic adornment factors (i.e., socially desirable and undesirable aspects). Moreover, results of regression analyses indicated that (1) self-esteem was positively predicted by socially desirable aspects of ethnic adornment (p’s < .05 in both studies); whereas (2) self-esteem was negatively predicted by socially undesirable aspects of ethnic adornment (p’s < .05 in the pilot study and < .10 in the main study). Implications for research on ethnic identity are discussed.     

Viewer perspective affects central bottleneck requirements in spatial translation tasks

A psychological refractory period (PRP) approach and the locus of slack logic were applied to examine the novel question of whether spatial translation processes can begin before the central bottleneck when effector or noneffector stimuli are processed from an egocentric (viewer-centered) perspective. In single tasks, trials requiring spatial translations were considerably slower than trials without translations (Experiment 1). Dual tasks consisted of tone discriminations (Task 1) and spatial translations (Task 2) using PRP methods with different manipulations on perceptual and response demands. When a viewer-centered perspective was used, the effect of spatial translation was reduced at short compared with long stimulus onset asynchronies (SOAs) when the potential for code overlap between tasks was removed (Experiments 2, 3, and 4); this finding supports the view that translation processes can begin before the central bottleneck. When an allocentric (non-viewer-centered) perspective was used (Experiment 5), the slowing associated with spatial translation was additive with SOA, suggesting that the processes of spatial translation cannot begin before the bottleneck. These findings highlight the importance of viewer perspective on central bottleneck requirements. Findings are further discussed in relation to the dorsal-ventral model of action and perception.