Peter J. Hand - US grants

The long-term objectives of this laboratory are: (1) to understand the mechanisms underlying the metabolic (functional) reorganization of the developing and established central nervous system (CNS) to peripheral or central nervous system damage, (2) to determine the behavioral consequences of such reorganizations, (3) to determine anatomical and physiological factors, which can enhance or retard CNS reorganization and subsequent recovery of function, and (4) to apply the knowledge gained from animal plasticity studies to the study of the functional plasticity-recovery of function relationship in human subjects possessing somesthetic deficits produced by lesions of the peripheral nervous system (e.g. peripheral nerve trauma, limb amputation, phantom-limb responses) or CNS (e.g. stroke, neoplasia). Such human studies would involve the use of the (11C) or (18F)-2DG, positron emission tomography technique, with which the principal investigator has had experience. The specific aims of this proposal are: (1) to determine the effects of CNS maturation on the extent of metabolic (functional) reorganization at both subcortical and cortical levels of the CNS, (2) to determine anatomical changes in first somatosensory (SI) cortex associated with the deafferentation-produced reorganization, (3) to determine the behavioral consequences of the observed metabolic reorganization, and (4) to determine the effects of intervention on the extent of metabolic (functional) reorganization. The precise organized rat facial vibrissa SI cortical "barrel" system will be utilized for such metabolic plasticity studies. The reorganization of the functional (metabolic) representation of a single, centrally-positioned facial vibrissa (C3), which is spared following denervation of the remaining vibrissae, will be examined at subcortical and cortical levels of neonatal and adult rats under different experimental conditions using the quantitative (14C)-2 deoxyglucose metabolic mapping technique. Behavioral consequences of the metabolic reorganization of the spared C3 vibrissa will be examined using a species-typical locomotor response tests.

Long-term objectives of this laboratory are: (1) to understand the mechanisms underlying altered functional (metabolic) organization in the central nervous system (CNS) produced by peripheral denervation or sensory disuse; (2) to determine anatomical and physiological factors that enhance or retard altered CNS organization and recovery of function; (3) to determine the behavioral consequences of altered CNS organization; (4) to apply this knowledge to the investigation of the functional plasticity recovery of function relationship in humans possessing lesion produced somesthetic deficits. Human studies would involve the use of the (llC) - 2DC position emission tomography technique. Results to date indicate a dynamic functional reorganization of the trigeminal afferent pathway and SI cortex following partial peripheral denervation. The extent of reorganization is, however, variable. The specific aims of our continued effort will identify factors which contribute to this variability: (1) to examine the effects of CNS maturation on the functional alterations at subcortical levels of the rat vibrissa-first somatosensory (SI) cortex system; (2) to determine the effects of chronic intervention on the functional alterations of the spared C3 (SC3) representation in the vibrissa pathway; (3) to determine the behavioral consequences of the SC3 metabolic alterations; (4) to determine the status of SC3 innervation to determine the CNS effects of variations in the peripheral innervation pattern and (5) to determine the influence of fiber competition associated with trigeminal and non-trigeminal related fiber systems on the altered SC3 functional representation in the vibrissa pathway. The precisely organized rat facial vibrissa-SI "barrel" system will be used to study denervation produced altered metabolic organization centrally. The altered functional representation of facial vibrissa C3, which is spared (SC3) following denervation of remaining vibrissae, will be examined at all levels of the vibrissa-SI cortex pathway of neonatal and adult rats under different experimental conditions using the quantitative (14C)-2 deoxyglucose technique. Behavioral consequences associated with the altered SC3 metabolic representation in the vibrissal pathway, will be examined using species-specific locomotor response tests.

Long-term objectives of this laboratory are: (1) to understand the mechanisms underlying altered functional (metabolic) organization in the central nervous system (CNS) produced by peripheral denervation or sensory disuse; (2) to determine anatomical and physiological factors that enhance or retard altered CNS organization and recovery of function; (3) to determine the behavioral consequences of altered CNS organization; (4) to apply this knowledge to the investigation of the functional plasticity recovery of function relationship in humans possessing lesion produced somesthetic deficits. Human studies would involve the use of the (llC) - 2DC position emission tomography technique. Results to date indicate a dynamic functional reorganization of the trigeminal afferent pathway and SI cortex following partial peripheral denervation. The extent of reorganization is, however, variable. The specific aims of our continued effort will identify factors which contribute to this variability: (1) to examine the effects of CNS maturation on the functional alterations at subcortical levels of the rat vibrissa-first somatosensory (SI) cortex system; (2) to determine the effects of chronic intervention on the functional alterations of the spared C3 (SC3) representation in the vibrissa pathway; (3) to determine the behavioral consequences of the SC3 metabolic alterations; (4) to determine the status of SC3 innervation to determine the CNS effects of variations in the peripheral innervation pattern and (5) to determine the influence of fiber competition associated with trigeminal and non-trigeminal related fiber systems on the altered SC3 functional representation in the vibrissa pathway. The precisely organized rat facial vibrissa-SI "barrel" system will be used to study denervation produced altered metabolic organization centrally. The altered functional representation of facial vibrissa C3, which is spared (SC3) following denervation of remaining vibrissae, will be examined at all levels of the vibrissa-SI cortex pathway of neonatal and adult rats under different experimental conditions using the quantitative (14C)-2 deoxyglucose technique. Behavioral consequences associated with the altered SC3 metabolic representation in the vibrissal pathway, will be examined using species-specific locomotor response tests.

Long-term objectives of this laboratory are: (1) to understand the mechanisms underlying altered functional (metabolic) organization in the central nervous system (CNS) produced by peripheral denervation or sensory disuse; (2) to determine anatomical and physiological factors that enhance or retard altered CNS organization and recovery of function; (3) to determine the behavioral consequences of altered CNS organization; (4) to apply this knowledge to the investigation of the functional plasticity recovery of function relationship in humans possessing lesion produced somesthetic deficits. Human studies would involve the use of the (llC) - 2DC position emission tomography technique. Results to date indicate a dynamic functional reorganization of the trigeminal afferent pathway and SI cortex following partial peripheral denervation. The extent of reorganization is, however, variable. The specific aims of our continued effort will identify factors which contribute to this variability: (1) to examine the effects of CNS maturation on the functional alterations at subcortical levels of the rat vibrissa-first somatosensory (SI) cortex system; (2) to determine the effects of chronic intervention on the functional alterations of the spared C3 (SC3) representation in the vibrissa pathway; (3) to determine the behavioral consequences of the SC3 metabolic alterations; (4) to determine the status of SC3 innervation to determine the CNS effects of variations in the peripheral innervation pattern and (5) to determine the influence of fiber competition associated with trigeminal and non-trigeminal related fiber systems on the altered SC3 functional representation in the vibrissa pathway. The precisely organized rat facial vibrissa-SI "barrel" system will be used to study denervation produced altered metabolic organization centrally. The altered functional representation of facial vibrissa C3, which is spared (SC3) following denervation of remaining vibrissae, will be examined at all levels of the vibrissa-SI cortex pathway of neonatal and adult rats under different experimental conditions using the quantitative (14C)-2 deoxyglucose technique. Behavioral consequences associated with the altered SC3 metabolic representation in the vibrissal pathway, will be examined using species-specific locomotor response tests.