Lack of Concentration

Lack of concentration or reduced concentration ability. 

Persons most commonly affected: Any age group and both sexes.
Organ or part of body involved: Brain
Causes and risk factors: Simple reasons for reduced concentration include: Fatigue; Tiredness; Drowsiness; Sleep debt; Anxiety; Marijuana - a form of cannabis; Hyperactivity; Cannabis; ADHD; Inattention; and Minimal brain disorder.