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Speed of visual object recognition is facilitated after active manual exploration of objects relative to passive visual processing alone. Manual exploration allows viewers to select important information about object structure that may facilitate recognition. Viewpoints where the objects' axis of elongation is perpendicular or parallel to the line of sight are selected more during exploration, recognized faster than other viewpoints, and afford the most information about structure when object movement is controlled by the viewer. Prior work used virtual object exploration in active and passive viewing conditions, limiting multisensory structural object information. Adding multisensory information to encoding may change accuracy of overall recognition, viewpoint selection, and viewpoint recognition. We tested whether the known active advantage for object recognition would change when real objects were studied, affording visual and haptic information. Participants interacted with 3D novel objects during manual exploration or passive viewing of another's object interactions. Object recognition was tested using several viewpoints of rendered objects. We found that manually explored objects were recognized more accurately than objects studied through passive exploration and that recognition of viewpoints differed from previous work. [ABSTRACT FROM AUTHOR]

Letter production through handwriting creates visual experiences that may be important for the development of visual letter perception. We sought to better understand the neural responses to different visual percepts created during handwriting at different levels of experience. Three groups of participants, younger children, older children, and adults, ranging in age from 4.5 to 22 years old, were presented with dynamic and static presentations of their own handwritten letters, static presentations of an age-matched control's handwritten letters, and typeface letters during fMRI. First, data from each group were analyzed through a series of contrasts designed to highlight neural systems that were most sensitive to each visual experience in each age group. We found that younger children recruited ventral-temporal cortex during perception and this response was associated with the variability present in handwritten forms. Older children and adults also recruited ventral-temporal cortex; this response, however, was significant for typed letter forms but not variability. The adult response to typed letters was more distributed than in the children, including ventral-temporal, parietal, and frontal motor cortices. The adult response was also significant for one's own handwritten letters in left parietal cortex. Second, we compared responses among age groups. Compared to older children, younger children demonstrated a greater fusiform response associated with handwritten form variability. When compared to adults, younger children demonstrated a greater response to this variability in left parietal cortex. Our results suggest that the visual perception of the variability present in handwritten forms that occurs during handwriting may contribute to developmental changes in the neural systems that support letter perception.

Verb learning is difficult for children (Gentner, [Gentner, D., 1982]), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, [Kersten, A.W., 2002]). Here we investigate how well 4- and 5-year-old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24-hour delay.

Previous research has suggested that handwriting letters may be an important exerciser to facilitate early letter understanding. Experimental studies to date, however, have not investigated whether this effect is general to any visual-motor experience or specific to handwriting letters. In the present work, we addressed this issue by testing letter knowledge using three measures in preschool children before and after a school-based intervention. Participants were divided into four training groups (letter-writing, digit-writing, letter-viewing, digit-viewing) that either wrote letters or digits or viewed letters or digits, twice a week for 6 weeks. We hypothesized that the visual-motor experience of handwriting letters or digits would improve letter knowledge more than viewing experience and that this effect would not be specific to training with letters. Our results demonstrated that the writing groups improved in letter recognition--one component of letter knowledge--significantly more than the viewing groups. The letter-writing group did not improve significantly more than the digit-writing group. These results suggest that visual-motor practice with any symbol could lead to increases in letter recognition. We interpret this novel finding as suggesting that any handwriting will increase letter recognition in part because it facilitates gains in visual-motor coordination.

Asking children to gesture while being taught a concept facilitates their learning. Here, we investigated whether children benefitted equally from producing gestures that reflected speech (speech-gesture matches) versus gestures that complemented speech (speech-gesture mismatches), when learning the concept of palindromes. As in previous studies, we compared the utility of each gesture strategy to a speech alone strategy. Because our task was heavily based on language ability, we also considered children's phonological competency as a predictor of success at posttest. Across conditions, children who had low phonological competence were equally likely to perform well at posttest. However, gesture use was predictive of learning for children with high phonological competence: Those who produced either gesture strategy during training were more likely to learn than children who used a speech alone strategy. These results suggest that educators should be encouraged to use either speech-gesture match or mismatch strategies to aid learners, but that gesture may be especially beneficial to children who possess basic skills related to the new concept, in this case, phonological competency. Results also suggest that there are differences between the cognitive effects of naturally produced speech-gesture matches and mismatches, and those that are scripted and taught to children.

Visually guided action is a ubiquitous component of human behavior, but the neural substrates that support the development of this behavior are unknown. Here we take an initial step in documenting visual-motor system development in the young (4-to 7-year- old) child. Through functional MRI and by using a new technique to measure the mechanisms underlying real-time visually guided action in the MRI environment, we demonstrate that children rely primarily on the IPS and cerebellum for this complex behavior. This pattern is consistent across three different visually guided actions, suggesting generalizability of these neural substrates across such tasks. However, minor differences in neural processing across tasks were also demonstrated. Overall, results are interpreted as demonstrating that the functions of the dorsal stream can be viewed as fairly mature in the young child. These results provide a benchmark for future studies that aim to understand the development of the neural circuitry for visually guided action. [ABSTRACT FROM AUTHOR]