Can dogs use vocal intonation as a social referencing cue in an object choice task?

Evidence from the literature indicates that dogs' choices can be influenced by human-delivered social cues, such as pointing, and pointing combined with facial expression, intonation (i.e., rising and falling voice pitch), and/or words. The present study used an object choice task to investigate whether intonation conveys unique information in the absence of other salient cues. We removed facial expression cues and speech information by delivering cues with the experimenter's back to the dog and by using nonword vocalizations. During each trial, the dog was presented with pairs of the following three vocal cues: Positive (happy-sounding), Negative (sad-sounding), and Breath (neutral control). In Experiment 1, where dogs received only these vocal cue pairings, dogs preferred the Positive intonation, and there was no difference in choice behavior between Negative or Breath. In Experiment 2, we included a point cue with one of the two vocal cues in each pairing. Here, dogs preferred containers receiving pointing cues as well as Negative intonation, and preference was greatest when both of these cues were presented together. Taken together, these findings indicate that dogs can indeed extract information from vocal intonation alone, and may use intonation as a social referencing cue. However, the effect of intonation on behavior appears to be strongly influenced by the presence of pointing, which is known to be a highly salient visual cue for dogs. It is possible that in the presence of a point cue, intonation may shift from informative to instructive.

Variations in an African Grey parrot's speech patterns following ignored and denied requests.

Communicative competence is one measure of an individual's ability to navigate conversations with social partners. The current study explored the possibility of basic communicative competence in a non-mammal speaker, a speech-using African Grey parrot. Spontaneous conversations between one Grey named Cosmo and her caregiver were recorded, from which three corpora (i.e., bodies of text) of Cosmo's vocalizations were developed: (1) Baseline: Vocalizations containing no requests, (2) Ignored Requests: Vocalizations immediately following Cosmo's caregiver ignoring Cosmo's requests, and (3) Denied Requests: Vocalizations immediately following Cosmo's caregiver denying Cosmo's requests. The distributions of social (e.g., "I love you," kiss sounds) and nonsocial (e.g., answering machine beeps, "That's squirrel") vocalizations, as well as speech and nonword vocalizations, were statistically different across the three corpora. Additionally, qualitative analysis of the datasets indicated Cosmo was persistent in repeating vocalizations when denied and ignored, and interrupted her caregiver more often when requests were denied compared to ignored. Neither repetition nor interruption occurred during the Baseline conversations. The data indicate that despite the outcome being the same (i.e., request was unmet), Cosmo treated an ignored request differently than a denied request, modifying her vocalizations in accord with the specific context. Such modification is evidence of basic communicative competence.

Higher-order semantic structures in an African Grey parrot's vocalizations: evidence from the hyperspace analog to language (HAL) model.

Previous research has described the significant role that social interaction plays in both the acquisition and use of speech by parrots. The current study analyzed the speech of one home-raised African Grey parrot (Psittacus erithacus erithacus) across three different social contexts: owner interacting with parrot in the same room, owner and parrot interacting out of view in adjacent rooms, and parrot home alone. The purpose was to determine the extent to which the subject's speech reflected an understanding of the contextual substitutability (e.g., the word street can be substituted in context for the word road) of the vocalizations that comprised the units in her repertoire (i.e., global co-occurrence of repertoire units; Burgess in Behav Res Methods Instrum Comput 30:188-198, 1998; Lund and Burgess in Behav Res Methods Instrum Comput 28:203-208, 1996). This was accomplished via the human language model hyperspace analog to language (HAL). HAL is contextually driven and bootstraps language "rules" from input without human intervention. Because HAL does not require human tutelage, it provided an objective measure to empirically examine the parrot's vocalizations. Results indicated that the subject's vocalization patterns did contain global co-occurrence. The presence of this quality in this nonhuman's speech may be strongly indicative of higher-order cognitive skills.

When and how well can human-socialized capuchins match actions demonstrated by a familiar human?

Capuchin monkeys have provided uneven evidence of matching actions they observe others perform. In accord with theories emphasizing the attentional salience of object movement and spatial relationships, we predicted that human-reared monkeys would better match events in which a human demonstrator moved an object into a new relation with another object or surface than other kinds of actions. Three human-reared capuchins were invited repeatedly by a familiar human to perform a fixed set of actions upon objects or upon their bodies, using the "Do as I do" procedure. Actions directed at the body were matched less reliably than actions involving objects, and actions were matched best when the monkey looked at the demonstration for at least 2 sec and performed its action within a few seconds after the demonstration. The most commonly matched actions were those that one monkey performed relatively often when the experiment began. One monkey partially reproduced three novel actions (out of 48 demonstrations), all three involving moving or placing objects, and two of which it also performed following other demonstrations. These findings contribute convergent evidence that capuchin monkeys display social facilitation of activity, enhanced interest in particular objects and emulation of spatial outcomes. This pattern can support the development of shared manipulative skills, as evident in traditions of foraging and tool use in natural settings. The findings do not suggest that human rearing substantively altered capuchins' ability or interest in matching the actions of a familiar human, although visual attention to the human demonstrator may have been greater in these monkeys than in normally reared monkeys.

Social context influences the vocalizations of a home-raised African Grey parrot (Psittacus erithacus erithacus).

Home-raised African Grey parrots (Psittacus erithacus erithacus) exhibit strong social bonding with their human companions. We examined how 1 parrot's vocal production (speech and nonword sounds) changed with social context with respect to descriptive measures of the vocalizations and their thematic content. We videotaped the parrot in 4 social conditions: subject home alone, subject and owner in the same room, owner in a separate room within hearing range, and owner and experimenter conversing in the same room as the parrot but ignoring her. Linguistic analysis revealed the parrot's repertoire consisted of 278 "units" ranging in length from 1 to 8 words or sounds. Rate of vocalization and vocabulary richness (i.e., the number of different units used) differed significantly, and many vocalizations were context-specific. For example, when her owner was in the room and willing to reciprocate communication, the parrot was more likely to use units that, in English, would be considered solicitations for vocal interaction (e.g., "Cosmo wanna talk"). When she and her owner were in separate rooms, the subject was significantly more likely to use units that referenced her spatial location and that of her owner (e.g., "Where are you"), suggesting she uses specific units as an adaptation of the wild parrot contact call. These results challenge the notion that parrots only imitate speech and raise interesting questions regarding the role of social interaction in learning and communicative competence in an avian species.

Towards a neurobiology of creativity in nonhuman animals.

We propose a cognitive and neurobiological framework for creativity in nonhuman animals based on the framework previously proposed by Kaufman and Kaufman (2004), with additional insight from recent animal behavior research, behavioral neuroscience, and creativity theories. The additional information has lead to three major changes in the 2004 model-the addition of novelty seeking as a subcategory of novelty recognition, the addition of specific neurological processing sites that correspond to each of the processes, and the transformation of the model into a spectrum in which all three levels represent different degrees of the creative process (emphasis on process) and the top level, dubbed innovation, is defined by the creative product. The framework remains a three-level model of creativity. The first level is composed of both the cognitive ability to recognize novelty, a process linked to hippocampal function, and the seeking out of novelty, which is linked to dopamine systems. The next level is observational learning, which can range in complexity from imitation to the cultural transmission of creative behavior. Observational learning may critically depend on the cerebellum, in addition to cortical regions. At the peak of the model is innovative behavior, which can include creating a tool or exhibiting a behavior with the specific understanding that it is new and different. Innovative behavior may be especially dependent upon the prefrontal cortex and/or the balance between left and right hemisphere functions.