Sociodemographic correlates of food habits among school adolescents (12–15 year) in north Gaza Strip

Background: There is little information about meal patterns and food consumption of adolescents in Palestine. The objective of this study was to describe the association between sociodemographic factors and food intake, and meal patterns among Palestinian school adolescents (12–15 year) in North Gaza Strip. Methods: A cross-sectional study was conducted in 2002 comprising 944 subjects in 10 schools in Gaza city, Jabalia village and Jabalia refugee camp. Self-administered questionnaires were filled in by students and parents to obtain data on frequency of meals, food intake and sociodemographic characteristics. Results: High household socioeconomic status (SES) was associated with the increased number of meals and the increased intakes of many nutritious foods such as; animal food items, fruits and vegetables and dairy foods. The percentage of adolescents having breakfast daily of high and low SES was 74.5% vs 55% in boys and 65.6% vs 45% in girls. The percentage of girls with refugee status who had lunch was higher (90.2%) compared to the local citizen girls (83.9%), (p = 0.03). Girls were less likely to skip daily lunch (OR = 0.55, 95% CI = 0.36–0.87, p = 0.01) compared to boys. Risk of skipping lunch was three times higher among adolescents living in the village compared to Gaza well-off area (OR = 3.3, 95% CI = 1.72–6.31, p < 0.001). Adolescents who were having lunch daily were less likely to skip breakfast or dinner. Only 11.6% of boys and 16.2% of girls consumed fruits daily. In multivariate analysis, SES was positively associated with food frequency intake scores in both genders. Boys from the refugee camp and the village had a significant higher consumption of fruits and vegetables than boys from high and low income area in Gaza City, while it was the opposite in girls. Conclusion: Meal skipping is common, particularly among those of low SES and the intakes of many nutritious foods such as animal food items, fruits and vegetables and dairy foods seem to be low among adolescents of low SES. The results of this study could be used as an important baseline for future monitoring of the nutritional situation of adolescents.Abdallah H Abudayya, Hein Stigum, Zumin Shi, Yehia Abed and Gerd Holmboe-Ottese

The Natural Statistics of Audiovisual Speech

Humans, like other animals, are exposed to a continuous stream of signals, which are dynamic, multimodal, extended, and time varying in nature. This complex input space must be transduced and sampled by our sensory systems and transmitted to the brain where it can guide the selection of appropriate actions. To simplify this process, it's been suggested that the brain exploits statistical regularities in the stimulus space. Tests of this idea have largely been confined to unimodal signals and natural scenes. One important class of multisensory signals for which a quantitative input space characterization is unavailable is human speech. We do not understand what signals our brain has to actively piece together from an audiovisual speech stream to arrive at a percept versus what is already embedded in the signal structure of the stream itself. In essence, we do not have a clear understanding of the natural statistics of audiovisual speech. In the present study, we identified the following major statistical features of audiovisual speech. First, we observed robust correlations and close temporal correspondence between the area of the mouth opening and the acoustic envelope. Second, we found the strongest correlation between the area of the mouth opening and vocal tract resonances. Third, we observed that both area of the mouth opening and the voice envelope are temporally modulated in the 2–7 Hz frequency range. Finally, we show that the timing of mouth movements relative to the onset of the voice is consistently between 100 and 300 ms. We interpret these data in the context of recent neural theories of speech which suggest that speech communication is a reciprocally coupled, multisensory event, whereby the outputs of the signaler are matched to the neural processes of the receiver

Monkeys and Humans Share a Common Computation for Face/Voice Integration

Speech production involves the movement of the mouth and other regions of the face resulting in visual motion cues. These visual cues enhance intelligibility and detection of auditory speech. As such, face-to-face speech is fundamentally a multisensory phenomenon. If speech is fundamentally multisensory, it should be reflected in the evolution of vocal communication: similar behavioral effects should be observed in other primates. Old World monkeys share with humans vocal production biomechanics and communicate face-to-face with vocalizations. It is unknown, however, if they, too, combine faces and voices to enhance their perception of vocalizations. We show that they do: monkeys combine faces and voices in noisy environments to enhance their detection of vocalizations. Their behavior parallels that of humans performing an identical task. We explored what common computational mechanism(s) could explain the pattern of results we observed across species. Standard explanations or models such as the principle of inverse effectiveness and a “race” model failed to account for their behavior patterns. Conversely, a “superposition model”, positing the linear summation of activity patterns in response to visual and auditory components of vocalizations, served as a straightforward but powerful explanatory mechanism for the observed behaviors in both species. As such, it represents a putative homologous mechanism for integrating faces and voices across primates

Chimpanzee lip-smacking facilitates cooperative behaviour

Signalling plays an important role in facilitating and maintaining affiliative or cooperative interactions in social animals. Social grooming in primates is an example of an interaction that requires coordination between partners but little is known about communicative behaviours facilitating this activity. In this study, we analysed the communication of wild chimpanzees of Budongo Forest, Uganda, as they entered and maintained a naturally occurring cooperative interaction: social grooming. We found that lip-smacking, a distinct multimodal oral gesture produced during grooming, coordinated this activity. Lip-smacking at the beginning of grooming bouts was significantly more often followed by longer and reciprocated bouts than silent grooming initiations. Lip-smacks were more likely to be produced when the risk of termination of the interaction by the recipient was high, for instance when grooming vulnerable body parts. Groomers were also more likely to produce lip-smacks during face-to-face grooming where the visual aspect of the signal could be perceived. Data are consistent with the hypothesis that chimpanzee lip-smacks function to coordinate and prolong social grooming, suggesting that this oral signal is an example of a communicative behaviour facilitating cooperative behaviour in chimpanzees

Multisensory vocal communication in primates and the evolution of rhythmic speech

The integration of the visual and auditory modalities during human speech perception is the default mode of speech processing. That is, visual speech perception is not a capacity that is “piggybacked” on to auditory-only speech perception. Visual information from the mouth and other parts of the face is used by all perceivers to enhance auditory speech. This integration is ubiquitous and automatic and is similar across all individuals across all cultures. The two modalities seem to be integrated even at the earliest stages of human cognitive development. If multisensory speech is the default mode of perception, then this should be reflected in the evolution of vocal communication. The purpose of this review is to describe the data that reveal that human speech is not uniquely multisensory. In fact, the default mode of communication is multisensory in nonhuman primates as well but perhaps emerging with a different developmental trajectory. Speech production, however, exhibits a unique bimodal rhythmic structure in that both the acoustic output and the movements of the mouth are rhythmic and tightly correlated. This structure is absent in most monkey vocalizations. One hypothesis is that the bimodal speech rhythm may have evolved through the rhythmic facial expressions of ancestral primates, as indicated by mounting comparative evidence focusing on the lip-smacking gesture