Anxiety doesn't necessarily cause concentration problems as its own symptom. In fact, it could be argued that anxiety actually improves concentration. Anxiety is the activation of your fight or flight system, which is meant to keep you safe from harm by ensuring you're running away or fighting without distraction.
The first set up is a standard 20-25 pound test rig (depending on the size of the tuna) with a size 1 to 2/0 hook depending on bait size and the size of the tuna. Fluorocarbon leader can be super effective if the fish are touchy (biting infrequently). This set up will be the primary bait fishing set up.
A can of tuna contains about 5 oz. and lists 2 oz., or 1/4 cup, as an appropriate single serving size on the nutrition label. The American Dietetic Association food exchange lists calculate using 1 oz. servings of fish. Many restaurants and home cooks serve more than one serving's worth in a single meal.