Software Tools Design for Analysis of Kinematic and Force Measurements in Chick Embryo

The objective of my thesis was to develop software tools for the analysis of kinematic measurements and force measurements from chick embryos. The ultimate goal behind my objective is to assist in chick embryonic studies to understand the contribution of sensory input to the development of motor circuitry. For this reason, I designed analytical tools in MATLAB software to analyze kinematic recordings and force signal recordings. Then, I applied these tools to recording of embryos whose movements have been obstructed with a force probe to test the hypothesis that embryos utilize sensory information to coordinate movements. For kinematic analyses, embryos were videotaped at embryonic day 9 (E9) and E11 and digitized for obstructed and unobstructed conditions. Results indicated that there was a significant change observed at the ankle joint in E11s in the presence of obstruction. Analysis of spatial utilization in response to the obstruction showed the adaptive behavior of E11 embryos. An additional observation is that the embryo is inclined to use new space in the presence of obstruction. However, E9 embryos did not show significant changes in spatial usage. For force measurements in these experiments, a small strain gage was used as a force probe that measures force by converting it to a voltage signal. In view of the fact that a single sensor only provided information for force produced along a line, it was necessary to use two probes aligned orthogonal to each other. The program calculated the magnitude and direction of the force applied by comparing the ratio of forces measured by the two sensors. Results indicated that the force generation is higher in E11 embryos than in E9 embryos. Overall, results indicate that E11 embryos show a greater possibility to adapt to the complexities of spatial restriction. I expect that the designed software tools hold relevance not only in our specific field of study but also in the general area of kinematic movement analysis, gait analysis, robotics, etc

Novel Esophago-Cortical Responses in Unsedated Human Neonates Discovered Upon Concurrent Provocative Manometry and Functional Near-Infrared Spectroscopy (Fnirs)

Our objectives were to establish feasibility to perform fNIRS in neonates and to characterize the HbO and HbD concentration changes in the vicinity of fronto-parietal cerebral cortex evoked upon esophageal provocation

Esophageal Reflexes Modulate Frontoparietal Response in Neonates: Novel Application of Concurrent NIRS and Provocative Esophageal Manometry

Central and peripheral neural regulation of swallowing and aerodigestive reflexes is unclear in human neonates. Functional near infrared spectroscopy (NIRS) is a noninvasive method to measure changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbD). Pharyngoesophageal manometry permits evaluation of aerodigestive reflexes. Modalities were combined to investigate feasibility and to test neonatal frontoparietal cortical changes during pharyngoesophageal (visceral) stimulation and/or swallowing. Ten neonates (45.6 ± 3.0 wk postmenstrual age, 4.1 ± 0.5 kg) underwent novel pharyngoesophageal manometry concurrent with NIRS. To examine esophagus-brain interactions, we analyzed cortical hemodynamic response (HDR) latency and durations during aerodigestive provocation and esophageal reflexes. Data are presented as means ± SE or percent. HDR rates were 8.84 times more likely with basal spontaneous deglutition compared with sham stimuli (P = 0.004). Of 182 visceral stimuli, 95% were analyzable for esophageal responses, 38% for HDR, and 36% for both. Of analyzable HDR (n = 70): 1) HbO concentration (μmol/l) baseline 1.5 ± 0.7 vs. 3.7 ± 0.7 poststimulus was significant (P = 0.02), 2) HbD concentration (μmol/l) between baseline 0.1 ± 0.4 vs. poststimulus −0.5 ± 0.4 was not significant (P = 0.73), and 3) hemispheric lateralization was 21% left only, 29% right only, and 50% bilateral. During concurrent esophageal and NIRS responses (n = 66): 1) peristaltic reflexes were present in 74% and HDR in 61% and 2) HDR was 4.75 times more likely with deglutition reflex vs. secondary peristaltic reflex (P = 0.016). Concurrent NIRS with visceral stimulation is feasible in neonates, and frontoparietal cortical activation is recognized. Deglutition contrasting with secondary peristalsis is related to cortical activation, thus implicating higher hierarchical aerodigestive protective functional neural networks

Esophageal Reflexes Modulate Frontoparietal Response in Neonates: Novel Application of Concurrent NIRS and Provocative Esophageal Manometry

Central and peripheral neural regulation of swallowing and aerodigestive reflexes is unclear in human neonates. Functional near infrared spectroscopy (NIRS) is a noninvasive method to measure changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbD). Pharyngoesophageal manometry permits evaluation of aerodigestive reflexes. Modalities were combined to investigate feasibility and to test neonatal frontoparietal cortical changes during pharyngoesophageal (visceral) stimulation and/or swallowing. Ten neonates (45.6 ± 3.0 wk postmenstrual age, 4.1 ± 0.5 kg) underwent novel pharyngoesophageal manometry concurrent with NIRS. To examine esophagus-brain interactions, we analyzed cortical hemodynamic response (HDR) latency and durations during aerodigestive provocation and esophageal reflexes. Data are presented as means ± SE or percent. HDR rates were 8.84 times more likely with basal spontaneous deglutition compared with sham stimuli (P = 0.004). Of 182 visceral stimuli, 95% were analyzable for esophageal responses, 38% for HDR, and 36% for both. Of analyzable HDR (n = 70): 1) HbO concentration (μmol/l) baseline 1.5 ± 0.7 vs. 3.7 ± 0.7 poststimulus was significant (P = 0.02), 2) HbD concentration (μmol/l) between baseline 0.1 ± 0.4 vs. poststimulus −0.5 ± 0.4 was not significant (P = 0.73), and 3) hemispheric lateralization was 21% left only, 29% right only, and 50% bilateral. During concurrent esophageal and NIRS responses (n = 66): 1) peristaltic reflexes were present in 74% and HDR in 61% and 2) HDR was 4.75 times more likely with deglutition reflex vs. secondary peristaltic reflex (P = 0.016). Concurrent NIRS with visceral stimulation is feasible in neonates, and frontoparietal cortical activation is recognized. Deglutition contrasting with secondary peristalsis is related to cortical activation, thus implicating higher hierarchical aerodigestive protective functional neural networks