Effects of Sustained Load Carrying on Reward Learning in the Rat Model for Neurodevelopmental Disorders

Neurodevelopmental disorder is a complex brain disorder that significantly affects the way children perceive and process incoming sensory information for functional purposes. Sensory processing plays an important role in typical development and is aberrant in various neurodevelopemental disorders when developing children are learning to attain the competencies in dealing the environmental challenges. Weight vest is an apparatus which provides a deep, sustain loading pressure to achieve the calming and organizing effects of the central nervous system. Although the benefits of loading pressure have reported on improving sensory processing in children with neurodevelopmental disorder, empirical evidences in associated with neurophysiological and clinical aspects are relative rare. Among the brain regions, a role of amygdala processing has been suggested to underlie the sensory stimuli by the opioid receptors, but processing function of the amygdala in associative with reward learning in neurodevelopmental disorder is yet not clear. For purpose of better understanding the neurophysiological changes of amygdala processing without the added risk of harming an actual human being during the processes, an animal model is designed to investigate the effects of sustain load carrying on reward learning for neurotoxin-induced neurodevelopmental disorder in this three-year proposal. In the 1st stage of research, the rat model for neurodevelopmental disorder is established through prenatally exposed to valproic acid as well as early postnatally exposed to ibotenic acid. Postnatal growth and maturation development in accompanied with behavior testing are used to identify the developmental trajectories and the behavioral validation of the rat model. In the 2nd stage of research, neurophysiological recording is implemented by implantation of micro-wire electrode assembly to the amygdala of rats. By using the telemetric data acquisition system, chronic extracellular neuronal activities in amygdala of freely moving rats with sustain load carrying are recorded during the reward learning paradigm. After the end of behavioral testing, the immunohistological and protein quantitative analyses are performed to verify the amount of μ-opioid receptors in amygdala pre- and post-sustain load carrying. In the 3rd stage of research, clinical performance and safety profile for pre-clinical testing are evaluated based on the results of neurophysiological data and behavior performance recorded from rats with neurodevelopemtnal disorder under sustain load carrying. Depending on the results, the quantitative dose and duration effects are expected to provide the information for clinical reasoning and intervention strategies to clinical application of sustain load carrying for persons with neurodevelopmental disorder.

Project ID:PB10207-1799
External Project ID:NSC102-2320-B182-032