Development of upper visual field bias for faces in infants

The spatial location of the face and body seen in daily life influences human perception and recognition. This contextual effect of spatial locations suggests that daily experience affects how humans visually process the face and body. However, it remains unclear whether this effect is caused by experience, or innate neural pathways. To address this issue, we examined the development of visual field asymmetry for face processing, in which faces in the upper visual field were processed preferentially compared to the lower visual field. We found that a developmental change occurred between 6 and 7 months. Older infants aged 7–8 months showed bias toward faces in the upper visual field, similar to adults, but younger infants of 5–6 months showed no such visual field bias. Furthermore, older infants preferentially memorized faces in the upper visual field, rather than in the lower visual field. These results suggest that visual field asymmetry is acquired through development, and might be caused by the learning of spatial location in daily experience.     

Asian Parents’ Perception of Child Weight Status: A Systematic Review

Parental perception of a child’s weight is important in determining parenting and feeding styles, which relate to childhood obesity. Evidence suggests this perception can vary by ethnicity. The purpose of this review was to explore Asian parents’ child weight perception and examine factors related to Asian parents’ child weight misperception. A systematic literature review was conducted on eight studies between 2000 and 2016 through the databases of CINAHL, Cochrane Reviews, PsycINFO, Medline, and PubMed. Searching key words were Asians, Asian-Americans, weight perception, and parents. The review revealed that all eight studies identified child weight misperception, but with highly varying results (ranging from 29.7 to 89.2%). Factors that influenced the accuracy of a parent’s child weight perception included maternal BMI, parental gender and age, child’s BMI, child’s own weight perception, child’s gender and age, and child’s birth order and birth weight. Misperception about their children’s weight is prevalent among Asian parents. Anthropometric measurement of a child, rather than a parent’s reporting of a child’s weight, should be used to educate Asian parents regarding childhood obesity. Health care professionals should be aware of misperceptions when developing and providing a culturally appropriate intervention to address overweight/obesity among Asian children, which might include improving weight perception.     

Development of Rigid Motion Perception in Response to Radially Expanding Optic Flow

A radially expanding flow with a linear positive speed gradient is perceived as a rigid object approaching the observer, whereas such a flow having no or a reduced speed gradient is perceived as a non‐rigid, two‐dimensionally deforming object (De Bruyn & Orban, 1990). We tested elementary school‐aged children (younger children, 6–9 years, and older children, 9–11 years) and adults (20–22 years) to examine the development of the perception of rigidity. The results suggest that the perception of rigidity in response to a radial flow pattern with a speed gradient is similar in older (but not younger) children and adults. The development of rigidity perception from a radial flow pattern may be related to the maturation of the dorsal and ventral visual pathways during the elementary school years. Copyright © 2016 John Wiley & Sons, Ltd.     

The seeds of spatial grammar in the manual modality

Sign languages modulate the production of signs in space and use this spatial modulation to refer back to entities—to maintain coreference. We ask here whether spatial modulation is so fundamental to language in the manual modality that it will be invented by individuals asked to create gestures on the spot. English speakers were asked to describe vignettes under 2 conditions: using gesture without speech, and using speech with spontaneous gestures. When using gesture alone, adults placed gestures for particular entities in non-neutral locations and then used those locations to refer back to the entities. When using gesture plus speech, adults also produced gestures in non-neutral locations but used the locations coreferentially far less often. When gesture is forced to take on the full burden of communication, it exploits space for coreference. Coreference thus appears to be a resilient property of language, likely to emerge in communication systems no matter how simple.     

The greatest lower bound to the reliability of a test and the hypothesis of unidimensionality

To assess the reliability of congeneric tests, specifically designed reliability measures have been proposed. This paper emphasizes that such measures rely on a unidimensionality hypothesis, which can neither be confirmed nor rejected when there are only three test parts, and will invariably be rejected when there are more than three test parts. Jackson and Agunwamba's (1977) greatest lower bound to reliability is proposed instead. Although this bound has a reputation for overestimating the population value when the sample size is small, this is no reason to prefer the unidimensionality-based reliability. Firstly, the sampling bias problem of the glb does not play a role when the number of test parts is small, as is often the case with congeneric measures. Secondly, glb and unidimensionality based reliability are often equal when there are three test parts, and when there are more test parts, their numerical values are still very similar. To the extent that the bias problem of the greatest lower bound does play a role, unidimensionality-based reliability is equally affected. Although unidimensionality and reliability are often thought of as unrelated, this paper shows that, from at least two perspectives, they act as antagonistic concepts. A measure, based on the same framework that led to the greatest lower bound, is discussed for assessing how close is a set of variables to unidimensionality. It is the percentage of common variance that can be explained by a single factor. An empirical example is given to demonstrate the main points of the paper. The authors are obliged to Henk Kiers for commenting on a previous version. Gregor Sočan is now at the University of Ljubljana.     

The effect of support ratio on infants' perception of illusory contours

We used a preferential looking technique to investigate the effect of support ratio (a ratio of the physically specified contours to the total edge length) on the perception of Kanizsa illusory contours in infants aged 3-8 months. Previous work has shown that for adult observers the illusory-contour strength increases proportionally with the support ratio. When the support ratio was relatively high (66%), infants preferred illusory contours to non-illusory figures by 3-4 months of age (experiment 1). In contrast, only infants 7-8 months old showed this preference for illusory contours when the support ratio was reduced to 37% (experiment 3). Further, infants showed no preference for an outline version of the illusory-contour figure, which produced no illusory contours (experiment 2). This result confirms that the infants' preference reflects their perception of illusory contours. Our results show that (i) illusory-contour perception emerges at around 3-4 months of age, but (ii) that this ability is very limited until around 7-8 months of age.     

Two‐ to three‐month‐old infants prefer moving face patterns to moving top‐heavy patterns

Newborn infants prefer face‐like patterns over non‐face‐like patterns. This preference is explained by newborns' preference for a “top‐heavy” configuration, that is, for geometric patterns that have more elements in the upper part than in the lower part of the configuration (Simion, Valenza, Macchi Cassia, Turati, & Umiltà, 2002). However, for 3‐month‐old infants, face preference cannot be explained only by a preference for “top‐heaviness” because they prefer veridical face images over top‐heavy images. The present study used geometric patterns to investigate whether 2‐ to 3‐month‐old infants' preference for face patterns exceeds their preference for top‐heavy configurations. In Experiment 1, we revealed that the infants preferred the face pattern to the top‐heavy pattern only when the internal elements of the patterns were presented with face‐like movements. This facilitative effect of internal movement was observed again in Experiment 2, in which the patterns were presented with non‐face‐like movements. These results suggest that 2‐ to 3‐month‐olds' preference for geometric face patterns is greater than their preference for top‐heavy patterns only when aided by the movement of internal elements.     

The movement of internal facial features elicits 7 to 8‐month‐old infants' preference for face patterns

A preference for static face patterns is observed in newborns and disappears around 3 months after birth. A previous study has demonstrated that 5‐month‐old infants prefer schematic faces only when the internal features are moving, suggesting that face‐specific movement enhances infants' preference. The present study investigates the facilitative effect of the movement of internal facial features on infants' preference. To examine infants' preference, we used animated face patterns consisting of a head‐shaped contour and three disk blobs. The inner blobs expanded and contracted to represent the opening and closing of the eyes and mouth, and were constrained to open and close only in a biologically possible vertical direction resembling the facial muscle structure. We compared infants' preferential looking time for this vertically moving (VM) face pattern with their looking time for a horizontally moving (HM) face pattern in which blobs transformed at the same speed in a biologically impossible, horizontal direction. In Experiment 1, 7 to 8‐month‐olds preferred the VM to the HM, but 5 to 6‐month‐olds did not. However, the preference was diminished in both cases when the moving face patterns were presented without contour (Experiment 2). Our results suggest that internal facial features with vertical movements promote face preference in 7 to 8‐month‐olds. Copyright © 2011 John Wiley & Sons, Ltd.     

Perception of Mooney faces by young infants: the role of local feature visibility, contrast polarity, and motion

We examined the ability of young infants (3- and 4-month-olds) to detect faces in the two-tone images often referred to as Mooney faces. In Experiment 1, this performance was examined in conditions of high and low visibility of local features and with either the presence or absence of the outer head contour. We found that regardless of the presence of the outer head contour, infants preferred upright over inverted two-tone face images only when local features were highly visible (Experiment 1a). We showed that this upright preference disappeared when the contrast polarity of two-tone images was reversed (Experiment 1b), reflecting operation of face-specific mechanisms. In Experiment 2, we investigated whether motion affects infants' perception of faces in Mooney faces. We found that when the faces appeared to be rigidly moving, infants did show an upright preference in conditions of low visibility of local features (Experiment 2a). Again the preference disappeared when the contrast polarity of the image was reversed (Experiment 2b). Together, these results suggest that young infants have the ability to integrate fragmented image features to perceive faces from two-tone face images, especially if they are moving. This suggests that an interaction between motion and form rather than a purely motion-based process (e.g., structure from motion) facilitates infants' perception of faces in ambiguous two-tone images.     

When Do Speakers Use Gestures to Specify Who Does What to Whom? The Role of Language Proficiency and Type of Gestures in Narratives

Previous research has found that iconic gestures (i.e., gestures that depict the actions, motions or shapes of entities) identify referents that are also lexically specified in the co-occurring speech produced by proficient speakers. This study examines whether concrete deictic gestures (i.e., gestures that point to physical entities) bear a different kind of relation to speech, and whether this relation is influenced by the language proficiency of the speakers. Two groups of speakers who had different levels of English proficiency were asked to retell a story in English. Their speech and gestures were transcribed and coded. Our findings showed that proficient speakers produced concrete deictic gestures for referents that were not specified in speech, and iconic gestures for referents that were specified in speech, suggesting that these two types of gestures bear different kinds of semantic relations with speech. In contrast, less proficient speakers produced concrete deictic gestures and iconic gestures whether or not referents were lexically specified in speech. Thus, both type of gesture and proficiency of speaker need to be considered when accounting for how gesture and speech are used in a narrative context.