Potential study participants will be identified one of two ways, either by the treating physician in clinic when the decision is made to pursue surgery or by researchers monitoring the OR schedule. When a potential participant is identified by the treating physician in clinic, they will ask the patient if study personnel may call them to discuss the study. If the patient agrees to be contacted, the surgeon will alert study personnel who will call the patient to explain the study and arrange the initial study (screening) visit. Study personnel will monitor the OR schedule and call any potential patients the surgeons have not already identified in clinic. In this case, patients will be informed over the phone that their surgeon has granted permission to contact them regarding the study. Surgeons will be made aware when their patients have been approached over the phone, and updated accordingly if the patient agrees to the screening visit and is subsequently enrolled in the study. All screening visits will occur at the OSU Pre-operative Assessment Center (OPAC). When possible the screening visit will co-inside with pre-operative testing per the Anesthesia Department at OPAC.

Informed consent will occur at the initial screening visit which is to take place approximately 2 weeks prior to surgery, but no less than 8 days pre-op. At this visit, a member of the research team will obtain demographic information (gender, education level), historical medical information, and information regarding medication usage. The researcher will perform the Mini-Mental Status Exam (MMSE) - the modified version (see attached document), Self Administered Gerocognitve Form (SAGE) - all four versions (see attached questionnaires), Geriatric Depression Scale, Charlson Comorbidity Index, Postoperative Quality Recovery Scale (PQRS), and Short-form 36 Health Related Quality of Life Measure. Patients meeting inclusion criteria will be randomized to either the cognitive exercise or control group. Patients in the cognitive exercise group will be given a tablet with preinstalled access to Lumosity (Lumos Labs, San Francisco, CA, USA), a cognitive exercise software application which will be used in this study. Each participant in the cognitive exercise group will be expected to complete 1 hour of Lumosity brain exercise daily for a minimum of 8 days prior to surgery, equaling an effective 'dose' at least 10 hours. Playing time will be determined either by: (a) the actual in-game playing time; or (b) as calculated by the research team during the Screening Visit (see the "Subject Diary"). The Lumosity software allows for monitoring of participant compliance by researchers. Patients in the control group will carry out their normal activities prior to surgery.

All patients will undergo surgery as planned. On the day of surgery, prior to proceeding to the operating room, patients will be assessed with the Confusion Assessment Method (CAM) to confirm no presence of delirium pre-operatively. In the Post-anesthesia Recovery Unit, a different member of the research team (blinded to the patient's group assignment) will repeat the CAM to assess for PD. While hospitalized, pain scores determined using the Verbal Analog Scale and narcotic use will be obtained from the electronic medical record with at least 8 hour frequency (entered by registered nurses). All participants will be evaluated by a blinded researcher using the combined CAM/Memorial Delirium Assessment Scale (MDAS) at 7:30AM ± 1.5 hrs and 6:30PM ± 1.5 hrs for PD on subsequent post-op days until discharge. Additionally, the PQRS will be completed at each 6:30PM ± 1.5 hrs assessment. The PQRS, MMSE, and SAGE will be repeated just prior to discharge or on POD 7. A different form for the SAGE examination, as well as alternate number and word sequences for the PQRS and MMSE assessments, will be used in order to reduce the potential influence of the learning effect. At the end of this visit, active patient participation is complete. For subjects discharged before POD 7, the PQRS will be given again via telephone. Follow-up visits will be conducted on POD 30 and POD 90 via telephone. The PQRS will be obtained on POD 30, and the PQRS, GDS, and SF-36 will be obtained on POD 90. The research team will also periodically check the medical record during this time for readmissions and provider notes related to medical events. Participation is complete after POD 90.