Reaching and grasping of objects are overt reflections of planning and adjustment to environmental demands. By manipulating the cognitive and motor demands in tasks, one can study infants' anticipation of contact with an object by measuring their motor adaptations during a single reach and across repeated reaching. The use of infrared video recording allows variation in visual cues, while motion analysis system technology allows precise measurement of hand position in 3-dimensional space, hand orientation, and hand movement in relation to object movement. From our research in the previous grant period we know that infants 5- to 7-months-old do not have to see their hands in order to guide an accurate reach, even when the object is moving. We now propose to study reaching in infants in three sets of studies whose goal is to understand how infants use perceptual information to plan and guide action. The first set of studies takes advantage of the tendency of infants to orient their hands to match an object's orientation, which facilitates grasping. We will investigate the type and amount of visual and auditory information necessary to support this preparatory orienting of the hand. Some studies will feature rotating rods whose motion is sometimes seen and sometimes must be inferred. The second set of studies will vary task constraints to study infants' acceptance or avoidance of awkward grips in order to achieve a goal. The third set of studies will manipulate visual information and predictability of moving objects to determine if infants change strategies to cope with these demands. These studies encompass perceptual, motor, and cognitive development in infants, and will track developmental changes across a wide age range, from 5 to 16 months. A second set of studies will be conducted in a Neonatal Intensive Care Unit. Some studies will be observational and some will manipulate contingent events. The purpose of this work is to determine what naturally occurring contingencies the preterm infant experiences in the NICU, and to what extent the infant responds to these contingencies both physiologically and behaviorally. Last, we will determine whether the preterm infant can learn and retain artificial contingencies when the stimulus and the response are adapted to their capabilities.
| Laporte, Justin L; Ren-Patterson, Renee F; Murphy, Dennis L et al. (2008) Refining psychiatric genetics: from 'mouse psychiatry'to understanding complex human disorders. Behav Pharmacol 19:377-84 |
| Murphy, Dennis L; Fox, Meredith A; Timpano, Kiara R et al. (2008) How the serotonin story is being rewritten by new gene-based discoveries principally related to SLC6A4, the serotonin transporter gene, which functions to influence all cellular serotonin systems. Neuropharmacology 55:932-60 |
| Berthier, N E; Clifton, R K; McCall, D D et al. (1999) Proximodistal structure of early reaching in human infants. Exp Brain Res 127:259-69 |
| Clifton, R K; Freyman, R L; Litovsky, R Y et al. (1994) Listeners' expectations about echoes can raise or lower echo threshold. J Acoust Soc Am 95:1525-33 |
| Clifton, R K; Rochat, P; Robin, D J et al. (1994) Multimodal perception in the control of infant reaching. J Exp Psychol Hum Percept Perform 20:876-86 |
| Clifton, R K; Muir, D W; Ashmead, D H et al. (1993) Is visually guided reaching in early infancy a myth? Child Dev 64:1099-110 |
| Clifton, R K; Rochat, P; Litovsky, R Y et al. (1991) Object representation guides infants' reaching in the dark. J Exp Psychol Hum Percept Perform 17:323-9 |
| Clarkson, M G; Swain, I U; Clifton, R K et al. (1991) Newborns' head orientation toward trains of brief sounds. J Acoust Soc Am 89:2411-20 |
| Freyman, R L; Clifton, R K; Litovsky, R Y (1991) Dynamic processes in the precedence effect. J Acoust Soc Am 90:874-84 |
| Perris, E E; Myers, N A; Clifton, R K (1990) Long-term memory for a single infancy experience. Child Dev 61:1796-807 |
Showing the most recent 10 out of 18 publications
