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Handwriting is a complex visual-motor skill that affects early reading development. A large body of work has demonstrated that handwriting is supported by a widespread neural system comprising ventral-temporal, parietal, and frontal motor regions in adults. Recent work has demonstrated that this neural system is largely established by 8 years of age, suggesting that the development of this system occurs in young children who are still learning to read and write. We made use of a novel MRI-compatible writing tablet that allowed us to measure brain activation in 5–8-year-old children during handwriting. We compared activation during handwriting in children and adults to provide information concerning the developmental trajectory of the neural system that supports handwriting. We found that parietal and frontal motor involvement during handwriting in children is different from adults, suggesting that the neural system that supports handwriting changes over the course of development. Furthermore, we found that parietal and frontal motor activation correlated with a literacy composite score in our child sample, suggesting that the individual differences in the dorsal response during handwriting are related to individual differences in emerging literacy skills. Our results suggest that components of the widespread neural system supporting handwriting develop at different rates and provide insight into the mechanisms underlying the contributions of handwriting to early literacy development. [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. [ABSTRACT FROM AUTHOR]

Handwriting experience can have significant effects on the ability of young children to recognize letters. Why handwriting has this facilitative effect and how this is accomplished were explored in a series of studies using overt behavioral measures and functional neuroimaging of the brain in 4- to 5-year-old children. My colleagues and I showed that early handwriting practice affects visual symbol recognition because it results in the production of variable visual forms that aid in symbol understanding. Further, the mechanisms that support this understanding lay in the communication between visual and motor systems in the brain: Handwriting serves to link visual processing with motor experience, facilitating subsequent letter recognition skills. These results are interpreted in the larger context of the facilitatory effect that learning through action has on perceptual capabilities. [ABSTRACT FROM AUTHOR]

Handwriting letters has been shown to increase Blood Oxygen Level Dependent (BOLD) signal during letter perception in visual and motor brain regions relative to other types of training in preschool children. However, co-activation in these regions speaks neither to the presence of functional connections between them nor to the experiences by which such connections might be established. We investigated functional connectivity by applying generalized psychophysiological interactions analysis to BOLD data obtained from 4 to 6 year-old children after learning symbols through handwriting, tracing, or typing. Functional connections between (1) visual and parietal regions increased after all training conditions, (2) visual and ventral frontal regions increased after handwriting training with letters more than shapes, and (3) visual and dorsal frontal motor regions increased more after handwriting than typing letters. We conclude that visual-motor training creates functional connections among visual and motor brain regions that reflect different aspects of the handwriting experience. [ABSTRACT FROM AUTHOR]

Abstract: The role of experience in the development of brain mechanisms for face recognition is intensely debated. Experience with subordinate- and individual-level classification of faces is thought, by some, to be foundational in the development of the specialization of face recognition. Studying children with extremely intense interests (EII) provides an opportunity to examine experience-related changes in non-face object recognition in a population where face expertise is not fully developed. Here, two groups of school-aged children —one group with an EII with Pokémon cards and another group of age-matched controls — underwent fMRI while viewing faces, Pokémon characters, Pokémon objects, and Digimon characters. Pokémon objects were non-character Pokémon cards that experts do not typically individuate during game play and trading. Neither experts nor controls had previous experience with Digimon characters. As expected, experts and controls showed equivalent activation in the fusiform face area (FFA) with face stimuli. As predicted by the expertise hypothesis, experts showed greater activation than controls with Pokémon characters, and showed greater activation with Pokémon characters than Pokémon objects. Experts and controls showed equivalent activation with Digimon characters. However, heightened activation with Digimon characters in both groups suggested that there are other strong influences on the activation of the FFA beyond stimulus characteristics, experience, and classification level. By demonstrating the important role of expertise, the findings are inconsistent with a purely face-specific account of FFA function. To our knowledge, this is the first demonstration of the effects of expertise and categorization level on activation in the FFA in a group of typically developing children. [Copyright &y& Elsevier]

Abstract: In an age of increasing technology, the possibility that typing on a keyboard will replace handwriting raises questions about the future usefulness of handwriting skills. Here we present evidence that brain activation during letter perception is influenced in different, important ways by previous handwriting of letters versus previous typing or tracing of those same letters. Preliterate, five-year old children printed, typed, or traced letters and shapes, then were shown images of these stimuli while undergoing functional MRI scanning. A previously documented “reading circuit” was recruited during letter perception only after handwriting—not after typing or tracing experience. These findings demonstrate that handwriting is important for the early recruitment in letter processing of brain regions known to underlie successful reading. Handwriting therefore may facilitate reading acquisition in young children. [Copyright &y& Elsevier]

Actions influence perceptions, but how this occurs may change across the lifespan. Studies have investigated how object-directed actions (e.g., learning about objects through manipulation) affect subsequent perception, but how abstract actions affect perception, and how this may change across development, have not been well studied. In the present study, we address this question, teaching children (4-7 year-olds) and adults sung melodies, with or without an abstract motor component, and using functional Magnetic Resonance Imaging (fMRI) to determine how these melodies are subsequently processed. Results demonstrated developmental change in the motor cortices and Middle Temporal Gyrus. Results have implications for understanding sensori-motor integration in the developing brain, and may provide insight into motor learning use in some music education techniques. [ABSTRACT FROM AUTHOR]

Previous research shows that sensory and motor systems interact during verb perception, and that these interactions are formed through self-generated actions that refer to verb labels during development. Here we expand on these findings by investigating whether self-generated actions lead to sensori-motor interaction during sound perception and visual perception. The current research exposes young children to novel sounds that are produced by object movement through either a) actively exploring the objects and producing the sounds or b) by seeing and hearing an experimenter interact with the objects. Results demonstrate that the motor system was recruited during auditory perception only after learning involved self-generated interactions with objects. Interestingly, visual association regions were also active during both sound perception and visual perception after active exploratory learning, but not after passive observation. Therefore, in the developing brain, associations are built upon real-world interactions of body and environment, leading to sensori-motor representations of both objects and sounds. [ABSTRACT FROM AUTHOR]

Abstract: Although human experience is multisensory in nature, previous research has focused predominantly on memory for unisensory as opposed to multisensory information. In this work, we sought to investigate behavioral and neural differences between the cued recall of cross-modal audiovisual associations versus within-modal visual or auditory associations. Participants were presented with cue-target associations comprised of pairs of nonsense objects, pairs of nonsense sounds, objects paired with sounds, and sounds paired with objects. Subsequently, they were required to recall the modality of the target given the cue while behavioral accuracy, reaction time, and blood oxygenation level dependant (BOLD) activation were measured. Successful within-modal recall was associated with modality-specific reactivation in primary perceptual regions, and was more accurate than cross-modal retrieval. When auditory targets were correctly or incorrectly recalled using a cross-modal visual cue, there was re-activation in auditory association cortex, and recall of information from cross-modal associations activated the hippocampus to a greater degree than within-modal associations. Findings support theories that propose an overlap between regions active during perception and memory, and show that behavioral and neural differences exist between within- and cross-modal associations. Overall the current study highlights the importance of the role of multisensory information in memory. [Copyright &y& Elsevier]

Abstract: Behavioral, neuropsychological and neuroimaging research suggest a distributed network that is recruited when we interact with letters. For the first time, we combine several letter processing tasks in a single experiment to study why letters seem to engage such disparate processing areas. Using fMRI, we investigate how the brain responds to letters using tasks that should recruit systems for letter perception, letter writing, letter copying and letter imagery. We describe a network of five cortical regions including the left fusiform gyrus, two left pre-central areas, left cuneus and the left inferior frontal gyrus that are all selectively engaged during a 1-back matching paradigm with letters. Our results suggest involvement of these regions to different extents in different tasks. However, the regions also form an integrated network such that letter perception also engages motor regions while writing recruits letter-specific visual regions as well. We suggest that this distributed network is a direct result of our sensory–motor interactions with letters. [Copyright &y& Elsevier]

Research has provided strong evidence of multisensory convergence of visual and haptic information within the visual cortex. These studies implement crossmodal matching paradigms to examine how systems use information from different sensory modalities for object recognition. Developmentally, behavioral evidence of visuohaptic crossmodal processing has suggested that communication within sensory systems develops earlier than across systems; nonetheless, it is unknown how the neural mechanisms driving these behavioral effects develop. To address this gap in knowledge, BOLD functional Magnetic Resonance Imaging (fMRI) was measured during delayed match-to-sample tasks that examined intramodal (visual-to-visual, haptic-to-haptic) and crossmodal (visual-to-haptic, haptic-to-visual) novel object recognition in children aged 7–8.5 years and adults. Tasks were further divided into sample encoding and test matching phases to dissociate the relative contributions of each. Results of crossmodal and intramodal object recognition revealed the network of known visuohaptic multisensory substrates, including the lateral occipital complex (LOC) and the intraparietal sulcus (IPS). Critically, both adults and children showed crossmodal enhancement within the LOC, suggesting a sensitivity to changes in sensory modality during recognition. These groups showed similar regions of activation, although children generally exhibited more widespread activity during sample encoding and weaker BOLD signal change during test matching than adults. Results further provided evidence of a bilateral region in the occipitotemporal cortex that was haptic-preferring in both age groups. This region abutted the bimodal LOtv, and was consistent with a medial to lateral organization that transitioned from a visual to haptic bias within the LOC. These findings converge with existing evidence of visuohaptic processing in the LOC in adults, and extend our knowledge of crossmodal processing in adults and children. [ABSTRACT FROM AUTHOR]

Abstract: Visuohaptic inputs offer redundant and complementary information regarding an object׳s geometrical structure. The integration of these inputs facilitates object recognition in adults. While the ability to recognize objects in the environment both visually and haptically develops early on, the development of the neural mechanisms for integrating visual and haptic object shape information remains unknown. In the present study, we used functional Magnetic Resonance Imaging (fMRI) in three groups of participants, 4 to 5.5 year olds, 7 to 8.5 year olds, and adults. Participants were tested in a block design involving visual exploration of two-dimensional images of common objects and real textures, and haptic exploration of their three-dimensional counterparts. As in previous studies, object preference was defined as a greater BOLD response for objects than textures. The analyses specifically target two sites of known visuohaptic convergence in adults: the lateral occipital tactile–visual region (LOtv) and intraparietal sulcus (IPS). Results indicated that the LOtv is involved in visuohaptic object recognition early on. More importantly, object preference in the LOtv became increasingly visually dominant with development. Despite previous reports that the lateral occipital complex (LOC) is adult-like by 8 years, these findings indicate that at least part of the LOC is not. Whole-brain maps showed overlap between adults and both groups of children in the LOC. However, the overlap did not build incrementally from the younger to the older group, suggesting that visuohaptic object preference does not develop in an additive manner. Taken together, the results show that the development of neural substrates for visuohaptic recognition is protracted compared to substrates that are primarily visual or haptic. [Copyright &y& Elsevier]

Background A touchscreen interface permits rich user interactions for research in many fields, but is rarely found within a Magnetic Resonance Imaging (MRI) environment due to difficulties adapting conventional technologies to the strong electromagnetic fields. Conventional MR-compatible video display technology uses either large-screen displays that are placed outside of the bore of the MRI itself, or projectors located beyond the participant's reach, making touch interfaces impossible. New method Here, we describe the MR-compatibility of the ‘MRItab’ in terms of MR safety and image quality. The MRItab adapts inexpensive off-the-shelf components with special signal-driver circuitry and shielding to bring the touchscreen interface into the MR environment, without adversely affecting MRI image quality, thereby making touch interfaces possible. Results Our testing demonstrated that the functioning of the MRItab was not affected by the functioning of the MRI scanner and that the MRItab did not adversely affect the image data acquired. Participants were able to interact naturally with the MRItab during MRI scanning. Comparison with other method (s) The MRItab is the first MR-compatible touchscreen device with video-display screen capabilities designed for use in the MRI environment. This interactive digital device is the first to allow participants to see their hands directly as they interact with a touch-sensitive display screen, resulting in high ecological validity. Conclusions The MRItab provides a methodological advantage for research in many fields, given the realistic human-computer interaction it supports. [ABSTRACT FROM AUTHOR]

Abstract: A recent view of cortical functional specialization suggests that the primary organizing principle of the cortex is based on task requirements, rather than sensory modality. Consistent with this view, recent evidence suggests that a region of the lateral occipitotemporal cortex (LO) may process object shape information regardless of the modality of sensory input. There is considerable evidence that area LO is involved in processing visual and haptic shape information. However, sound can also carry acoustic cues to an object''s shape, for example, when a sound is produced by an object''s impact with a surface. Thus, the current study used auditory stimuli that were created from recordings of objects impacting a hard surface to test the hypothesis that area LO is also involved in auditory shape processing. The objects were of two shapes, rods and balls, and of two materials, metal and wood. Subjects were required to categorize the impact sounds in one of three tasks, (1) by the shape of the object while ignoring material, (2) by the material of the object while ignoring shape, or (3) by using all the information available. Area LO was more strongly recruited when subjects discriminated impact sounds based on the shape of the object that made them, compared to when subjects discriminated those same sounds based on material. The current findings suggest that activation in area LO is shape selective regardless of sensory input modality, and are consistent with an emerging theory of perceptual functional specialization of the brain that is task-based rather than sensory modality-based. [Copyright &y& Elsevier]

Abstract: Environmental events produce many sensory cues for identifying the action that evoked the event, the agent that performed the action, and the object targeted by the action. The cues for identifying environmental events are usually distributed across multiple sensory systems. Thus, to understand how environmental events are recognized requires an understanding of the fundamental cognitive and neural processes involved in multisensory object and action recognition. Here, we investigated the neural substrates involved in auditory and visual recognition of object-directed actions. Consistent with previous work on visual recognition of isolated objects, visual recognition of actions, and recognition of environmental sounds, we found evidence for multisensory audiovisual event-selective activation bilaterally at the junction of the posterior middle temporal gyrus and the lateral occipital cortex, the left superior temporal sulcus, and bilaterally in the intraparietal sulcus. The results suggest that recognition of events through convergence of visual and auditory cues is accomplished through a network of brain regions that was previously implicated only in visual recognition of action. [Copyright &y& Elsevier]

• We exposed expert guitarists to four types of familiar visual depictions. • We were able to equate motor actions while comparing the translation of vision to action across levels of abstraction. • During both the perception and translation of vision to action, whole brain contrasts revealed that parietal regions were more activated for abstract stimuli and an occipito-insular circuit that was more activated for concrete stimuli. • The current findings highlight that the degree of visual abstraction is an important factor modulating visual-motor processing. Using visual information to perform actions is a fundamental aspect of human behavior. Musicians commonly translate visual information into action using both concrete and abstract visual information. We exposed expert guitarists to four types of familiar visual depictions of action instruction including musical notation (very abstract), tablature (abstract), chord diagrams (more concrete), and actual pictures of guitars chords being formed (very concrete). These were shown during fMRI scanning as the guitarists formed the appropriate chords (as visually depicted) on a magnet safe guitar fret board with strings, or where they simply viewed the visual stimuli without an action. Whole brain contrasts revealed that the right precuneus was more active for abstract instruction while an occipito-insular circuit was more active for concrete instruction. The current findings highlight that the degree of over-learned visual abstraction is an important factor modulating visual-motor processing. [ABSTRACT FROM AUTHOR]