Waiting for more: the performance of domestic dogs (Canis familiaris) on exchange tasks

Five domestic dogs (Canis familiaris) were tested in a cooperative exchange task with an experimenter, as previously tested in non-human primates. In the first task, the dogs exchanged to maximise payoffs when presented with food items of differing quality. All consistently exchanged lower-value for higher-value rewards, as determined by their individual food preference, and exchanges corresponded significantly with the spontaneous preferences of three dogs. Next, all subjects demonstrated an ability to perform two and three exchanges in succession, to gain both qualitative and quantitatively increased rewards (group mean = 72 and 92% successful triple exchanges, respectively). Finally, the ability to delay gratification over increasing intervals was tested; the dogs kept one food item to exchange later for a larger item. As previously reported in non-human primates, there was considerable individual variation in the tolerance of delays, between 10 s and 10 min for the largest rewards. For those who reached longer time lags (>40 s), the dogs gave up the chance to exchange earlier than expected by each subject’s general waiting capacity; the dogs anticipated delay duration and made decisions according to the relative reward values offered. Compared to primates, dogs tolerated relatively long delays for smaller value rewards, suggesting that the socio-ecological history of domestic dogs facilitates their performance on decision-making and delay of gratification tasks.     

Communicative intentions in wild chimpanzees: persistence and elaboration in gestural signalling

We examine evidence for communicative intent during conspecific interactions in wild chimpanzees (Budongo Forest, Uganda), focusing on persistence in gestural communication. Previous research indicates that great apes have large gestural repertoires and produce gestural communication in a flexible and intentional manner, including the production of gesture sequences. Although there is a lack of consensus on the form and function of sequences, there is some evidence that sequences are produced when signallers fail to receive any response from a recipient. Here, we provide first systematic evidence for communicative persistence in wild chimpanzees. Rather than examining only the presence or absence of a response, we used the most commonly observed response to assign meanings to gestures and examined sequence production in relation to response congruency. Chimpanzees ceased communication if successful, but persevered when unsuccessful. Chimpanzees repeated gestures when a response partially matched their goal but substituted the original gesture when a response was incongruent. Persistence was also mediated by recipient intent to respond, with more sequences produced within competitive than affiliative contexts. Gestures within sequences were homogenous in semantic meaning and signallers continued until the response matched the assigned meaning of the initial gesture. Gestural sequence production was not primarily affective; gesture intensity (in terms of modality) did not increase within sequences. Chimpanzee gestural sequences emerged to achieve specific outcomes; given variability in recipient behaviour following initial gestures, signallers were flexible in their persistence towards these goals.     

The Content of Older Adults’ Autobiographical Memories Predicts the Beneficial Outcomes of Reminiscence Group Participation

Much research has investigated the beneficial outcomes of reminiscence groups, like guided autobiography groups. Few have assessed whether the content of the autobiographical memories shared during these groups, however, predicts beneficial outcomes. This is the main goal of the current study. Sixteen participants responded to questionnaires about depression, death attitudes, and psychological well-being before and after an 8-week reminiscence group. Results indicated that group participation decreased depression, lowered fear and avoidance of death, and improved death acceptance. The 41 memory narratives collected from group participants were content analyzed for affective, cognitive, and sensory processes. Analyses revealed that memory content predicted levels of depression after group participation. Specifically, memories with more positive affective words (e.g., happy) predicted less depressive symptoms, and memories with negative cognitive process words (e.g., perhaps) predicted more depressive symptoms. The implications for remembering life events in old age are discussed.     

Use of human visual attention cues by olive baboons (Papio anubis) in a competitive task

The ability of 4 olive baboons (Papio anubis) to use human gaze cues during a competitive food task was investigated. Three baboons used head orientation as a cue, and 1 individual also used eye direction alone. As the baboons did not receive prior training with gestural cues, their performance suggests that the competitive paradigm may be more appropriate for testing nonhuman primates than the standard object-choice paradigm. However, the baboons were insensitive to whether the experimenter could actually perceive the food item, and therefore the use of visual orientation cues may not be indicative of visual perspective-taking abilities. Performance was disrupted by the introduction of a screen and objects to conceal food items and by the absence of movement in cues presented.     

The relationship between self-esteem level, self-esteem stability, and cardiovascular reactions to performance feedback

The authors examined the notion that individuals with unstable high self-esteem possess implicit self-doubt. They adopted the framework of the biopsychosocial model of challenge and threat and assessed spontaneous cardiovascular reactions in the face of success versus failure performance feedback. Study 1 revealed predicted interactions between feedback condition, self-esteem level, and self-esteem stability, such that participants with unstable high self-esteem exhibited relative threat (a negative reaction) in the failure condition, whereas those with stable high self-esteem exhibited relative challenge (a positive reaction). Study 2 replicated these results and provided additional evidence against plausible alternative explanations.     

Origins of adolescents’ earliest memories

ABSTRACT

This prospective longitudinal study traced changes and individual differences in childhood amnesia over adolescence. A sample of 58 adolescents were followed from age 1-1/2 to age 16 years across 8 timepoints. At ages 12 (n?=?46) and 16 (n?=?51), adolescents completed an early memory interview. Early childhood measures included children’s self-awareness, attachment security, nonverbal memory, verbal memory, language, theory of mind, narrative, and the early reminiscing environment (mothers’ elaborative reminiscing). Adolescents continued to forget their earliest memories over adolescence, such that the age of first memory increased from 40 to 52 months from ages 12 to 16. The sole unique contributor to individual differences in age of earliest memory at both 12 and 16 years was mothers’ elaborative reminiscing, with adolescents recalling earlier memories if their mothers had reminisced more elaboratively with them during early childhood. At age 16, the role of maternal reminiscing was moderated by self-awareness at age 1-1/2. Mothers’ elaborative reminiscing mattered for the age of adolescents’ earliest memories only for children who showed lower levels of self-awareness as toddlers. This pattern suggests a buffering effect for the role of maternal reminiscing in children’s earliest memories, and supports integrated theories of childhood amnesia.