Role In Social Communication Research Articles

The specificity of action in the analysis of movements: Reaction to Fogel, 1992

We are pleased to have been invited to write a commentary on Alan Fogel’s paper in which he integrates sociocultural information into a dynamical systems approach to human movement. Working, as we both are, on perceptuo-motor development in infancy, we have developed a particular interest in an ecological approach to perception and action. Such an approach ‘seeks to account for order and variability in movement as emerging in evolution, development, and learning from physical and informational constraints, without assuming sources of organisation in cognitive or neural structures a priori’ (Warren 1990: 23). We are therefore delighted that Fogel proposes a theory of social communication and development which is not based on internalized schemes or codes to account for developmental change, but on the emergence of communicative forms following a dynamic process of mutual interaction between adult and child. We also agree with Fogel that movements play an important role in social communication. When Fogel reverses this claim, however, by arguing that all movements are to be understood socially, we must object.

The anal gland secretion of the European badger (Meles meles) and its role in social communication

The aim of this study was to investigate the chemical profile and hence the potential biological function of anal gland secretion in the European badger (Meles meles). Samples of secretion collected from wild and captive animals were analysed using gas chromatography. Analysis of whole secretion revealed the scent profiles of all samples to be remarkably similar. No evidence was found to suggest that the secretion contained information about the individual identity or sex of its producer, although some evidence was found of group differences in odour profile. Analysis of methylated samples revealed the secretion to be of low volatility, containing a number of long‐chain (> C14) fatty acids, 15 of which were identified. The results are consistent with the idea that badger anal gland secretion functions as a long‐term territory marker.

Do infants perceive emotions in static faces?

Human voices play a fundamental role in social communication, and areas of the adult “social brain” show specialization for processing voices and their emotional content (superior temporal sulcus, inferior prefrontal cortex, premotor cortical regions, amygdala, and insula) [1, 2, 3, 4, 5, 6, 7, 8]. However, it is unclear when this specialization develops. Functional magnetic resonance (fMRI) studies suggest that the infant temporal cortex does not differentiate speech from music or backward speech [9, 10], but a prior study with functional near-infrared spectroscopy revealed preferential activation for human voices in 7-month-olds, in a more posterior location of the temporal cortex than in adults [11]. However, the brain networks involved in processing nonspeech human vocalizations in early development are still unknown. To address this issue, in the present fMRI study, 3- to 7-month-olds were presented with adult nonspeech vocalizations (emotionally neutral, emotionally positive, and emotionally negative) and nonvocal environmental sounds. Infants displayed significant differential activation in the anterior portion of the temporal cortex, similarly to adults [1]. Moreover, sad vocalizations modulated the activity of brain regions involved in processing affective stimuli such as the orbitofrontal cortex [12] and insula [7, 8]. These results suggest remarkably early functional specialization for processing human voice and negative emotions.

Conditioned aversion to a taste perceived while grooming

Four experiments were conducted to determine how the characteristics of conditioned taste aversion (CTA), as described from studies conducted in the drinking and feeding contexts, applied in the grooming context. In Experiment 1, sodium saccharin was mixed with a “neutral-tasting” jelly and applied to the fur of male Sprague-Dawley® rats. Rats injected with LiCl after the applications strongly avoided saccharin solutions in subsequent 1-hr, 2-choice (saccharin solution vs water) drinking tests, whereas rats injected with NaCl or given plain jelly on the fur showed only an initial neophobic response to the saccharin solution. Thus, the taste of saccharin was perceived while grooming and the CTA formed in the grooming context generalized to drinking. In Experiments 2–4, we obtained evidence that: (a) rats discriminated between one intensity of saccharin applied to the fur and another used in the test solution; and (b) rats differentiated between qualities of the two tastants applied to the fur in that saccharin overshadowed NaCl; and (c) taste qualities were more important than toxic properties when two stimuli (saccharin, LiCl) were used (saccharin overshadowed NaCl in subsequent drinking tests). We speculate that taste while grooming might play a role in social communication in some vertebrates. Further, CTA and grooming might have uses in rodent control (e.g., in agricultural situations) not previously considered such as in delivering a non-attractive, low-salience toxin so that the taste of the crop overshadows that of the bait, and induces crop aversion.

The role of the electrosensory system in postural control of the weakly electric fish Eigenmannia virescens.

The role of the electrosensory inputs in postural control was examined in the weakly electric fish Eigenmannia virescens. These fish exhibit tonic postural tilt in response to a tilted plexiglas substrate in both transverse and longitudinal planes (rolling and head-up pitching responses, respectively), but not to electrically "transparent" agar substrate. The fish's pitching and rolling responses were abolished when the electrosensory inputs from the trunk were bilaterally eliminated even though the fish's visual and mechanosensory lateral-line systems remained intact. Unilateral lesion abolished the rolling response but not the pitching response. These results demonstrate the functional role of the electrosensory system in postural control, in addition to its known role in social communication and in object location, and the underlying neuronal mechanism is discussed.