Do rhesus monkeys (Macaca mulatta) attribute knowledge and ignorance to others?

The ability of 4 rhesus monkeys (Macaca mulatta) to understand the causal connection between seeing and knowing was investigated. The subjects were tested to determine if they could discriminate between information provided by experimenters who randomly alternated between roles of guesser and knower. In a series of tests, the knower either hid food under 1 of 3 cups or watched as someone else hid the food. The guesser waited outside the room or covered her or his head until the food was hidden. The subjects watched this procedure occur but could not see which cup the food was hidden under. The knower pointed to the correct cup while the guesser pointed to an incorrect one. None of the macaques provided any evidence that they realized the different states of knowledge possessed by the guesser and knower. The results are consistent with the hypothesis that rhesus macaques are incapable of making inferences about the mental states of others.     

CHIMPANZEES:

Abstract— Gaze following is a behavior that draws the human infant into perceptual contact with objects or events in the world to which others are attending One interpretation of the development of this phenomenon is that it signals the emergence of joint or shared attention, which may be critical to the development of theory of mind An alternative interpretation is that gaze following is a noncognitive mechanism that exploits social stimuli in order to orient the infant (or adult) to important events in the world We report experimental results that chimpanzees display the effect in response to both movement of the head and eyes in concert and eve movement alone Additional tests indicate that chimpanzees appear able to (a) project an imaginary line of sight through invisible space and (b) understand How that line of sight can be impeded by solid, opaque objects This capacity may have arisen because of its reproductive payoffs in the context of social competition with conspecifics, predation avoidance, or both.     

The influence of negative advertising frames on political cynicism and politician accountability

This research examined the influence of negative political advertising frames on the thoughts and feelings people generate in response to campaign advertising. Preparing and conducting this investigation involved the use of a multiple‐method strategy. Content analysis identified two advertising frames (i.e., candidate theme and ad hoc issue advertisements) and two experiments separately induced political cynicism and politician accountability. Three hundred and sixty people participated in the experimental studies, in which they read and responded, using a thought‐listing technique, to candidate theme or ad hoc issue negative advertisements. Results demonstrated that participants were more likely to generate cynical comments and hold politicians accountable for the country's ills when reading candidate theme advertisements than ad hoc issue advertisements. The results indicate that this contributes to a political climate of cynicism and may function to erode the electorate's overall trust in government.     

Theory of Mind experience sampling in typical adults

We explored the frequency with which typical adults make Theory of Mind (ToM) attributions, and under what circumstances these attributions occur. We used an experience sampling method to query 30 typical adults about their everyday thoughts. Participants carried a Personal Data Assistant (PDA) that prompted them to categorize their thoughts as Action, Mental State, or Miscellaneous at approximately 30 pseudo-random times during a continuous 10-h period. Additionally, participants noted the direction of their thought (self versus other) and degree of socializing (with people versus alone) at the time of inquiry. We were interested in the relative frequency of ToM (mental state attributions) and how prominent they were in immediate social exchanges. Analyses of multiple choice answers suggest that typical adults: (1) spend more time thinking about actions than mental states and miscellaneous things, (2) exhibit a higher degree of own- versus other-directed thought when alone, and (3) make mental state attributions more frequently when not interacting (offline) than while interacting with others (online). A significant 3-way interaction between thought type, direction of thought, and socializing emerged because action but not mental state thoughts about others occurred more frequently when participants were interacting with people versus when alone; whereas there was an increase in the frequency of both action and mental state attributions about the self when participants were alone as opposed to socializing. A secondary analysis of coded free text responses supports findings 1–3. The results of this study help to create a more naturalistic picture of ToM use in everyday life and the method shows promise for future study of typical and atypical thought processes.     

The Mentality of Apes Revisited

Although early comparative psychology was seriously marred by claims of our species'supremacy, the residual backlash against these archaic evolutionary views is still being felt, even though our understanding of evolutionary biology is now sufficiently advanced to grapple with possible cognitive specializations that our species does not share with closely related species. The overzealous efforts to dismantle arguments of human uniqueness have only served to show that most comparative psychologists working with apes have yet to set aside the antiquated evolutionary "ladder." Instead, they have only attempted to pull chimpanzees up to the ladder's highest imaginary rung — or perhaps, to pull humans down to an equally imaginary rung at the height of the apes. A true comparative science of animal minds, however, will recognize the complex diversity of the animal kingdom, and will thus view Homo sapiens as one more species with a unique set of adaptive skills crying out to be identified and understood.     

Meta-analytic techniques reveal that corvid causal reasoning in the Aesop’s Fable paradigm is driven by trial-and-error learning

The classic Aesop’s fable, Crow and the Pitcher, has inspired a major line of research in comparative cognition. Over the past several years, five articles (over 32 experiments) have examined the ability of corvids (e.g., rooks, crows, and jays) to complete lab-based analogs of this fable, by requiring them to drop stones and other objects into tubes of water to retrieve a floating worm (Bird and Emery in Curr Biol 19:1–5, 2009b; Cheke et al. in Anim Cogn 14:441–455, 2011; Jelbert et al. in PLoS One 3:e92895, 2014; Logan et al. in PLoS One 7:e103049, 2014; Taylor et al. in Gray R D 12:e26887, 2011). These researchers have stressed the unique potential of this paradigm for understanding causal reasoning in corvids. Ghirlanda and Lind (Anim Behav 123:239–247, 2017) re-evaluated trial-level data from these studies and concluded that initial preferences for functional objects, combined with trial-and-error learning, may account for subjects’ performance on key variants of the paradigm. In the present paper, we use meta-analytic techniques to provide more precise information about the rate and mode of learning that occurs within and across tasks. Within tasks, subjects learned from successful (but not unsuccessful) actions, indicating that higher-order reasoning about phenomena such as mass, volume, and displacement is unlikely to be involved. Furthermore, subjects did not transfer information learned in one task to subsequent tasks, suggesting that corvids do not engage with these tasks as variants of the same problem (i.e., how to generate water displacement to retrieve a floating worm). Our methodological analysis and empirical findings raise the question: Can Aesop’s fable studies distinguish between trial-and-error learning and/or higher-order causal reasoning? We conclude they cannot.     

Do chimpanzees seek explanations? Preliminary comparative investigations.

During the past decade, considerable effort has been devoted to understanding whether chimpanzees reason about unobservable variables as explanations for observable events. With respect to physical causality, these investigations have explored chimpanzees' understanding of gravity, force, mass, shape, and so on. With respect to social causality, this research has focused on the question of whether they reason about mental states such as emotions, desires, and beliefs. In the studies reported here, we explored whether the chimpanzee's natural motivation for object exploration is modulated by a cognitive system that seeks explanations for unexpected events. We confronted both chimpanzees and young children with simple tasks which occasionally could not be made to work. We coded their reactions to determine if they appeared to be searching for an apparent cause (or explanation) of the task failure. The results of these preliminary studies point to both similarities and differences in how young children and chimpanzees react to such circumstances.     

Development of young children's understanding that the recent past is causally bound to the present

The results of 6 studies (involving 304 children) suggested that 4- and 5-year-olds, but not 3-year-olds, understand that very recent past events determine the present. In Studies 1-3, 3- and 4-year-old children were introduced to 2 empty hiding locations. With children's backs to these locations, a camera recorded an experimenter secretly hiding a puppet in one of them. Children then viewed the videotape of what had just happened, along with another tape that depicted identical events except with a different child and with the puppet hidden in the other location. Only 4-year-olds were subsequently able to locate the puppet, even though 3-year-olds remembered the contents of the tapes and understood the equivalence between the video events and the real world. In Study 4, similar effects were obtained when a verbal analog of the test was presented to 3-5-year-olds. Studies 5 and 6 showed that when children observed 2 events in which they had just participated, only 5-year-olds understood that the most recent events were relevant.     

Inferences about guessing and knowing by chimpanzees (Pan troglodytes)

The visual perspective-taking ability of 4 chimpanzees (Pan troglodytes) was investigated. The subjects chose between information about the location of hidden food provided by 2 experimenters who randomly alternated between two roles (the guesser and the knower). The knower baited 1 of 4 obscured cups so that the subjects could watch the process but could not see which of the cups contained the reward. The guesser waited outside the room until the food was hidden. Finally, the knower pointed to the correct cup while the guesser pointed to an incorrect one. The chimpanzees quickly learned to respond to the knower. They also showed transfer to a novel variation of the task, in which the guesser remained inside the room and covered his head while the knower stood next to him and watched a third experimenter bait the cups. The results are consistent with the hypothesis that chimpanzees are capable of modeling the visual perspectives of others.