Catherine L. Reed

The Body-Inversion Effect

Researchers argue that faces are recognized via the configuration of their parts. An important behavioral finding supporting this claim is the face-inversion effect, in which inversion impairs recognition of faces more than nonface objects. Until recently, faces were the only class of objects producing the inversion effect for untrained individuals. This study investigated whether the inversion effect extends to human body positions, a class of objects whose exemplars are structurally similar to each other. Three experiments compared the recognition of upright and inverted faces, houses, and body positions using a forced-choice, same/different paradigm. For both reaction time and error data, the recognition of possible human body postures was more affected by inversion than the recognition of houses. Further, the recognition of possible human body postures and recognition of faces showed similar effects of inversion. The inversion effect was diminished for impossible body positions that violated the biomechanical constraints of human bodies. These data suggest that human body positions, like faces, may be processed configurally by untrained viewers.

Hands Up: Attentional Prioritization of Space Near the Hand

This study explored whether hand location affected spatial attention. The authors used a visual covert-orienting paradigm to examine whether spatial attention mechanisms--location prioritization and shifting attention--were supported by bimodal, hand-centered representations of space. Placing 1 hand next to a target location, participants detected visual targets following highly predictive visual cues. There was no a priori reason for the hand to influence task performance unless hand presence influenced attention. Results showed that target detection near the hand was facilitated relative to detection away from the hand, regardless of cue validity. Similar facilitation was found with only proprioceptive or visual hand location information but not with arbitrary visual anchors or distant targets. Hand presence affected attentional prioritization of space, not the shifting of attention.

Neural substrates of tactile object recognition ; An fMRI study

A functional magnetic resonance imaging (fMRI) study was conducted during which seven subjects carried out naturalistic tactile object recognition (TOR) of real objects. Activation maps, conjunctions across subjects, were compared between tasks involving TOR of common real objects, palpation of “nonsense” objects, and rest. The tactile tasks involved similar motor and sensory stimulation, allowing higher tactile recognition processes to be isolated. Compared to nonsense object palpation, the most prominent activation evoked by TOR was in secondary somatosensory areas in the parietal operculum (SII) and insula, confirming a modality‐specific path for TOR. Prominent activation was also present in medial and lateral secondary motor cortices, but not in primary motor areas, supporting the high level of sensory and motor integration characteristic of object recognition in the tactile modality. Activation in a lateral occipitotemporal area associated previously with visual object recognition may support cross‐modal collateral activation. Finally, activation in medial temporal and prefrontal areas may reflect a common final pathway of modality‐independent object recognition. This study suggests that TOR involves a complex network including parietal and insular somatosensory association cortices, as well as occipitotemporal visual areas, prefrontal, and medial temporal supramodal areas, and medial and lateral secondary motor cortices. It confirms the involvement of somatosensory association areas in the recognition component of TOR, and the existence of a ventrolateral somatosensory pathway for TOR in intact subjects. It challenges the results of previous studies that emphasize the role of visual cortex rather than somatosensory association cortices in higher‐level somatosensory cognition. Hum. Brain Mapping 21:236–246, 2004.

Turning Configural Processing Upside Down: Part and Whole Body Postures

Like faces, body postures are susceptible to an inversion effect in untrained viewers. The inversion effect may be indicative of configural processing, but what kind of configural processing is used for the recognition of body postures must be specified. The information available in the body stimulus was manipulated. The presence and magnitude of inversion effects were compared for body parts, scrambled bodies, and body halves relative to whole bodies and to corresponding conditions for faces and houses. Results suggest that configural body posture recognition relies on the structural hierarchy of body parts, not the parts themselves or a complete template match. Configural recognition of body postures based on information about the structural hierarchy of parts defines an important point on the configural processing continuum, between recognition based on first-order spatial relations and recognition based on holistic undifferentiated template matching.

Haptic Integration of Object Properties: Texture, Hardness, and Planar Contour

Planar objects varying in shape, texture, and hardness were classified under haptic exploration. Classes were defined by values on one dimension, or redundantly, by two or three dimensions. Response times and exploratory procedures (Lederman & Klatzky, 1987) were recorded. Experiment 1 showed that a second dimension speeded responses for all combinations (redundancy gain), but a third dimension produced no further effect. In Experiments 2 and 3, classification trials began with two redundant dimensions, and subsequently one was withdrawn (held constant). When texture and hardness varied redundantly, withdrawal of either increased response time--even when subjects were initially instructed to focus on one dimension. Joint exploration for texture and hardness dominated whenever the two varied redundantly and persisted despite withdrawal. Redundancy gains (Experiment 1), but not substantial withdrawal effects (Experiments 2 and 3), were observed for combinations of texture or hardness with planar contour, indicating less integration than between substance dimensions. Compatibility of exploratory procedures appears to constrain dimensional integration.

Conceptual Effects on Representational Momentum

Four experiments addressed the question of whether prior knowledge of an objects typical movement in the real world affects the representation of motion. Representational momentum (RM) is the tendency for the short-term memory representation of an object to undergo a transformation corresponding to the objects trajectory. Using the standard RM paradigm, the RM elicited by objects with different typical motions was compared. Results indicate that conceptual knowledge about an objects typical motion affects the magnitude of RM and, as such, the representation of motion.

Grab it! Biased attention in functional hand and tool space

This study explored whether functional properties of the hand and tools influence the allocation of spatial attention. In four experiments that used a visual-orienting paradigm with predictable lateral cues, hands or tools were placed near potential target locations. Results showed that targets appearing in the hand’s grasping space (i.e., near the palm) and the rake’s raking space (i.e., near the prongs) produced faster responses than did targets appearing to the back of the hand, to the back of the rake, or near the forearm. Validity effects were found regardless of condition in all experiments, but they did not interact with the target-in-grasping/raking-space bias. Thus, the topology of the facilitated space around the hand is, in part, defined by the hand’s grasping function and can be flexibly extended by functional experience using a tool. These findings are consistent with the operation of bimodal neurons, and this embodied component is incorporated into a neurally based model of spatial attention.

Rapid facial reactions to emotional facial expressions in typically developing children and children with autism spectrum disorder

Typical adults mimic facial expressions within 1000 ms, but adults with autism spectrum disorder (ASD) do not. These rapid facial reactions (RFRs) are associated with the development of social-emotional abilities. Such interpersonal matching may be caused by motor mirroring or emotional responses. Using facial electromyography (EMG), this study evaluated mechanisms underlying RFRs during childhood and examined possible impairment in children with ASD. Experiment 1 found RFRs to happy and angry faces (not fear faces) in 15 typically developing children from 7 to 12 years of age. RFRs of fear (not anger) in response to angry faces indicated an emotional mechanism. In 11 children (8-13 years of age) with ASD, Experiment 2 found undifferentiated RFRs to fear expressions and no consistent RFRs to happy or angry faces. However, as children with ASD aged, matching RFRs to happy faces increased significantly, suggesting the development of processes underlying matching RFRs during this period in ASD.

Nonverbal Channel Use in Communication of Emotion: How May Depend on Why

This study investigated the hypothesis that different emotions are most effectively conveyed through specific, nonverbal channels of communication: body, face, and touch. Experiment 1 assessed the production of emotion displays. Participants generated nonverbal displays of 11 emotions, with and without channel restrictions. For both actual production and stated preferences, participants favored the body for embarrassment, guilt, pride, and shame; the face for anger, disgust, fear, happiness, and sadness; and touch for love and sympathy. When restricted to a single channel, participants were most confident about their communication when production was limited to the emotions preferred channel. Experiment 2 examined the reception or identification of emotion displays. Participants viewed videos of emotions communicated in unrestricted and restricted conditions and identified the communicated emotions. Emotion identification in restricted conditions was most accurate when participants viewed emotions displayed via the emotions preferred channel. This study provides converging evidence that some emotions are communicated predominantly through different nonverbal channels. Further analysis of these channel-emotion correspondences suggests that the social function of an emotion predicts its primary channel: The body channel promotes social-status emotions, the face channel supports survival emotions, and touch supports intimate emotions.

Chronometric Comparisons of Imagery to Action: Visualizing Versus Physically Performing Springboard Dives

Motor imagery research emphasizes similarities between the mental imagery of an action and its physical execution. In this study, temporal differences between motor imagery and its physical performance as a function of performer expertise, skill complexity, and spatial ability were investigated. Physical execution times for springboard dives were compared with visualized execution times. Results indicate that physical and visualized performance times were not identical: Their relation is a function of dive complexity and diver expertise, but not their interaction. Relative to physical time, visualization time increased with increased complexity, suggesting the involvement of capacity-limited working memory. A nonmonotonic relation was found for expertise: Unlike experts or novices, visualization time for intermediates was significantly slower than physical time. These temporal differences are most consistent with schematic differences in skill representation. Intermediates may be relatively slowed by greater amounts of nonautomatized knowledge, as compared with the automatized knowledge of experts or the sparse knowledge of novices.