Participants randomized to the sham group will have the device earpiece applied at the same timepoints and for the same duration as the active group, but stimulation will not be turned on. tAN sessions will be administered up to four times per day for up to 20 days total. Sham tAN will be set to run for 30 minutes one hour prior to each planned morphine dose. When the 30-minute tAN session is complete, the system will be turned off and unplugged.

The NNNS is a comprehensive and systematic assessment of an infant's response to a variety of items including handling, spontaneous behavior, motor activity and self-soothing as indicators of neurobehavioral performance. The NNNS examines neurobehavioral organization, neurological reflexes, motor development, active and passive tone, and signs of stress and withdrawal of the at-risk and drug-exposed infant. The NNNS document the range of withdrawal and stress behavior likely to be observed in intervention with substance-exposed infants. The scale consists of 13 domains: habituation, attention, arousal, regulation, handling procedures, quality of movement, excitability, lethargy, nonoptimal reflexes, asymmetric reflexes, hypertonicity, hypotonicity, and stress/abstinence scale. Summary scores are calculated and compared with percentile scores to determine how an infant compares with an at-risk sample. The NNNS has good psychometric properties and reliability.

Defined as the date where all of the following criteria are met: age of at least 96 hours, a period of at least 48 hours without receipt of an opioid, at least 24 hours without respiratory support and with 100% oral feeding, at least 24 hours from initiation of maximum caloric density

The Neonatal Infant Pain Scale (NIPS) is a validated pain scale utilized in the NICU. There are six components to the NIPS: facial expression, crying, breathing patterns, arm and leg movements, and state of arousal. The NIPS scale scoring ranges from 0-7, with scores greater than 3 indicating discomfort. A score of 3 is similar to the pain level associated with a heel stick procedure to obtain blood and the maximum score of 6 is similar to a circumcision procedure without analgesia. This measure will be taken immediately prior to, during, and after tAN therapy.

The ASQ-3 is a parent-completed developmental screening tool that pinpoints developmental progress in children between the ages of one month to 5 ½ years. The ASQ-3 is a series of 19 age-specific questionnaires screening communication, gross motor, fine motor, problem-solving, and personal adaptive skills; results in a pass/fail score for domains.

The SP-2 is a set of norm-referenced, parent and teacher questionnaires designed to assess the sensory processing patterns of children from birth through 14 years, 11 months. Information obtained from the Sensory Profile 2 helps identify ways sensory processing may be contributing to or interfering with a child's participation in home, school, and community. There are five different forms selected based on age: 1) Infant Sensory Profile 2 - Birth to 6 months; 2) Toddler Sensory Profile - 7 to 35 months; 3) Child Sensory Profile 2 - 3 to 15 years; 4) Short Sensory Profile 2 - 3 to 15 years; and 5) School Companion Sensory Profile 2 - 3 to 15 years. Each of the forms includes some combination of Sensory System, Behavioral, and Sensory Pattern scores.

The BSID-III is an extensive formal developmental assessment tool for diagnosing developmental delays in early childhood. The BSID-III has three main subtests; the Cognitive Scale, the Language Scale, and the Motor Scale.