It seems you are concerned about the difficulties that you have been having with your attention, concentration, and memory. Without evaluating you and obtaining further history, it will be difficult for me to make a diagnosis. You may find it helpful to consult your primary care physician for a thorough medical evaluation. If medical causes (such as hypothyroidism or vitamin B-12 deficiency) are not found, it would be reasonable to have neurological or neuropsychological evaluation of your symptoms. Depression may cause diminished attention, concentration, and memory, which usually improve once the depression is treated.