SCUBA diving requires a high level of cognitive functioning, however, many divers anecdotally report poor memory and attentional skills while underwater. Few studies have documented cognitive deficits resulting from an open-water dive. Here, 23 divers completed both shallow (8 m) and deep (28 m) dives over two days in the open-water. The order of the dives was counterbalanced across participants. While at depth, they completed the State-Trait Anxiety Inventory to assess anxiety levels, learned and were tested on a list of 36 words, and completed the trail making task (TMT) to assess executive functioning. They also gave saliva samples to measure cortisol levels before and after each dive and completed the Profile of Mood States survey after each dive on the boat. Divers remembered fewer words, took longer to complete the TMT, and exhibited higher cortisol levels following a deep dive; they reported no changes in anxiety or mood states. The results contribute to our understanding of how cognition is affected by pressurized environments and has implications for divers, as well as others who engage in high-altitude sports
