Normal aging is characterized by a decline in several cognitive faculties, including the ability to adapt behavior in response to changing environmental contingencies.This ability, known as behavioral flexibility (BF) can be examined by the attentional set-shifting task (ASST), which has been used in rodent to evaluate cognitive impairment involving dysfunction in the prefrontal cortex (PFC), a core feature of several neuropsychiatric disorders. However, this test has not been used to assess BF in aged mice.We evaluated and compared BF between adult and aged mice with the ASST. Here, rodents learn the odor or texture of a digging pot, which is a relevant cue to find buried reward. We implemented this test and verified that the mice learned to pay attention and respond to relevant cue (digging medium) and ignore the irrelevant (odor), by pairing the reward with the medium. Preliminary results showed that all adult mice reached the learning criterion for each stage of the test. Conversely, aged mice did not reach the criterion in the stage that measures aspects of CF (Reversal 1) and exhibited a higher number of errors compared to adult mice.Given that normal aging has been associated with the disruption of neural systems that subserve BF, such as the hippocampus (HPC) and (mPFC), we are currently performing in vivo single unit and LFP recordings during the ASST to evaluate synchronization of neural activity patterns between HPC/mPFC axis. This research will allow us to understand the neurophysiological alterations associated to BF decline in aging.