Recent research has suggested insulin may be involved in how human's form and recall memories. This study is designed to look at how nasal insulin is used in the brain. Specifically, how insulin alters the various connections within brain regions that occur while adults perform simple attention and memory tasks. This study is divided into two parts: blood draw procedure and fMRI (functional Magnetic Resonance Imaging) procedure. The blood draw procedure is designed to look at the effects of intranasal insulin using a Precision Olfactory Delivery (POD) device on the blood levels of glucose and insulin. Those asked to participate will receiving a low-dose saline solution and low-dose of insulin through a nasal spray followed by a blood draw session to measure your blood glucose and insulin levels over a 90 minute period.