The focus of my research efforts rests with determining dysfunctional neural systems underlying disorders of sleep, and identifying interventions to overcome those disorders. Aberrant central and physiological control during sleep exerts serious consequences, including disruptions in breathing, motor control, blood pressure, mood, and cognition, and plays a major role in sudden infant death syndrome, congenital central hypoventilation, and sudden unexpected death in epilepsy, among other concerns. The disruptions can be traced to brain structural injury, leading to inappropriate outcomes. Identification of failing systems arose from the assessment of single neuron discharge in intact, freely moving and state-changing human and animal preparations within multiple systems, including serotonergic action and motor control sites. Optical imaging of chemosensitive, blood pressure and other breathing regulatory areas, especially during development, were useful to show integration of regional cellular action in modifying neural output. Identification of damaged neural sites in control and afflicted humans through structural and functional magnetic resonance imaging procedures helped to identify the sources of injury, and the nature of interactions between brain sites that compromise physiological systems and lead to failure. Interventions to overcome flawed regulatory processes were developed, and incorporate noninvasive neuromodulatory means to recruit ancient reflexes or provide peripheral sensory stimulation to assist breathing drive to overcome apnea, reduce the frequency of seizures, and support blood pressure in conditions where a failure to perfuse can lead to death.

Congenital central hypoventilation syndrome (CCHS) is characterized by shallow breathing during sleep due to negligible ventilatory sensitivity to hypercarbia and hypoxemia. It is diagnosed using a genetic test for PHOX2B mutation, which is not easily available. Neurally adjusted ventilatory assist (NAVA) is a spontaneous ventilatory mode that was designed basically for better adapting the ventilator to the patient by using electrical activity of diaphragm (EAdi) signals. We report a case of a 6-month-old infant who presented with recurrent apneas, where differential decrease in EAdi discharges during sleep using NAVA served as an early clue to the diagnosis of CCHS. Definitive diagnosis was later confirmed by genetic testing.
UNASSIGNED: Rauf A, Gupta D, Sachdev A, Gupta N, Gupta S, Kumar P, et al. Neurally Adjusted Ventilatory Assist: An Early Clue to Diagnosis of Congenital Central Hypoventilation Syndrome. IJCCM 2019;23(11):536-537.

Sleep-disordered breathing is accompanied by neural injury that affects a wide range of physiological systems which include processes for sensing chemoreception and airflow, driving respiratory musculature, timing circuitry for coordination of breathing patterning, and integration of blood pressure mechanisms with respiration. The damage also occurs in regions mediating emotion and mood, as well as areas regulating memory and cognitive functioning, and appears in structures that serve significant glycemic control processes. The injured structures include brain areas involved in hormone release and action of major neurotransmitters, including those playing a role in depression. The injury is reflected in a range of structural magnetic resonance procedures, and also appears as functional distortions of evoked activity in brain areas mediating vital autonomic and breathing functions. The damage is preferentially unilateral, and includes axonal projections; the asymmetry of the injury poses unique concerns for sympathetic discharge and potential consequences for arrhythmia. Sleep-disordered breathing should be viewed as a condition that includes central nervous system injury and impaired function; the processes underlying injury remain unclear.