AUTS2 Governs Cerebellar Development, Purkinje Cell Maturation, Motor Function and Social Communication

SummaryAutism susceptibility candidate 2 (AUTS2), a risk gene for autism spectrum disorders (ASDs), is implicated in telencephalon development. Because AUTS2 is also expressed in the cerebellum where defects have been linked to ASDs, we investigated AUTS2 functions in the cerebellum. AUTS2 is specifically localized in Purkinje cells (PCs) and Golgi cells during postnatal development. Auts2 conditional knockout (cKO) mice exhibited smaller and deformed cerebella containing immature-shaped PCs with reduced expression of Cacna1a. Auts2 cKO and knock-down experiments implicated AUTS2 participation in elimination and translocation of climbing fiber synapses, and restriction of parallel fiber synapse numbers. Auts2 cKO mice exhibited behavioral impairments in motor learning and vocal communications. Because Cacna1a is known to regulate synapse development in PCs, it suggests that AUTS2 is required for PC maturation to elicit normal development of PC synapses and thus the impairment of AUTS2 may cause cerebellar dysfunction related to psychiatric illnesses such as ASDs.

Vocalization can mediate male–male sexual interactions in Java sparrows

Same-sex sexual behaviors do not have direct fitness outcomes, but might be adaptive. This issue is often discussed in group-living animals, where social bonding is crucial. In our captive environment, around 33% of the Java-sparrow (Lonchura oryzivora) males kept in unisex cages have stable bonded partners. Those bonded males often perch side by side and show allopreening and joint-defensive behaviors towards others. In this study, we aimed to determine how males including such same-sex bonded individuals communicate with each other via vocalizations. We introduced same-sex pairs of Java sparrows, which were bonded or non-bonded, in sound-attenuated boxes and compared their recorded vocalizations with those from male–female pairs. For the male–male pairs, we identified two vocalizations that are usually exchanged between paired partners in intimate contexts: mating trills – which are usually emitted by females during successful copulation – and meowing calls – which are given when both members of the pair are in the nest at the same time. We found that males gave mating trills when their partner males were singing courtship songs, or performed trill duets, which sometimes also included meowing calls. Acoustic analyses revealed that there was no difference between male–male and male–female vocalizations. Meowing calls showed greater within-individual variation in duration and other acoustic parameters, but were similar in same-sex and mixed-sex contexts. Our results indicate that male–male pairs exchanged intimate vocal communications just like male–female couples.

Communication Behaviors of Infants With Hearing Loss and Their Hearing Mothers

This study documented communication behaviors of hearing mothers and infants with a hearing loss that had been identified before 9 months of age (Group HL). Their behaviors were compared with those of mothers and infants without hearing loss (Group H). Each group was composed of 18 dyads videotaped during mother-infant play with toys at 12- and 18-months. Group HL mothers produced more gestural and tactile communications (but similar numbers of vocal communications) compared to H mothers. In contrast with earlier reports, infants with and without hearing loss were similar in quantity of gestural and vocal expressive prelinguistic communication behaviors. Despite group similarities in quantity of prelinguistic communications, H infants as a group surpassed HL infants in expression of formal language by 18 months. There was considerable variation within each group in formal language expression, however, with performance of some HL infants matching that of H infants.

Vocal Communications of a Developmentally Delayed Child

Studies of first-word acquisition in typical language-learning children frequently take the form of diary studies. Comparable diary data from language-impaired children with developmental delays, however, are not currently available. This report describes the spontaneous vocalizations of a child with a developmental delay for 14 months, from the time he was age 6:5 to age 7:7. From a corpus of 285 utterances, 47 phonetic forms were identified and categorized. Analysis focused on semantic, communicative, and phonological usage patterns.

Perception of Emotion and Response to Teachers' Expectancy by Elementary School Children

Within each of 6 elementary school grades, a randomly selected 23% of the children were reported to their teachers as showing unusual potential for intellectual gains. All Ss were also administered a task designed to measure the accuracy of their perception of vocal communications of emotion by male and female speakers. After 4 mo. the “special” children scoring high in accuracy of perception of emotion as expressed by a female speaker showed significantly greater profit from the teachers' favorable expectations than did those low in accuracy. “Special” male Ss high in accuracy in perceiving emotion in a male showed significantly less profit from the expectancy after 4 mo. but significantly greater profit after being away from the teacher who received the expectancy for a 1-yr. period.