Adult Day Center Enhancement Act - Requires the Assistant Secretary for Aging to initiate a comprehensive survey of current adult day programs that provide care and support to individuals, including young adults, living with neurological diseases or conditions such as multiple sclerosis, Parkinson's disease, or traumatic brain injury. Requires the Assistant Secretary to identify ongoing successful adult day programs and which of these serve young adults with neurological diseases and conditions and develop a set of best practices to help guide the establishment and replication of additional successful adult day programs.

Directs the Assistant Secretary to establish a competitive grant program for awarding grants annually to fund adult day programs serving younger people with neurological diseases or conditions.

Defines an "adult day program" as a program that provides comprehensive and effective care and support services to individuals living with neurological diseases or conditions and to their family caregivers and that may assist participants in ways that: (1) maintain or improve their functional abilities or otherwise help them adjust to their changing functional abilities; (2) prevent the onset of complications associated with severe forms of the disease or condition; (3) promote alternatives to placement in nursing homes; (4) reduce the strain on family caregivers taking care of a family member living with such diseases or conditions; (5) focus on supporting the emotional, social, and intellectual needs of a younger adult population; or (6) address the needs of veterans living with such diseases or conditions.