San Antonio … Every 16 hours, give or take, the brain’s hippocampus makes six to nine thousand new neurons in the dentate gyrus, the portion of the brain which is believed to play a significant role in the preservation of episodic, or autobiographical, memory.

But how do those neurons store information? And, more importantly, how do they decide which information to store and which to discard?

University of Texas at San Antonio (UTSA) researcher Brian Derrick hopes to soon find out. The UTSA neurobiologist, a member of UTSA’s Department of Biology and its Neurosciences Institute, has won $917,000 in funding from the National Institutes of Health to research these and other related questions.

According to Derrick, the key lies in the difference between learning and memory.

“Learning is the acquisition of new knowledge,” he notes. “Memory is the persistence of learning over time. This kind of memory does not simply involve ‘what’ and ‘where’ events occurred; ‘when’ is also a crucial variable. We believe the continual generation of new neurons in both rats and humans serve as a temporal marker for highly similar memories. Because time also plays a role in memories, the contribution of these new neurons to episodic memory is the focus of this four-year grant.”

Although memory loss is most commonly associated with aging, it is also symptomatic of more debilitating diseases, including Alzheimer’s disease, Parkinson’s disease and Huntington’s disease, which collectively afflict 9.3 million people around the world.