What are the aftereffects of a mild concussion?

The vast majority of patients with mild concussions do not experience significant aftereffects. With one to three months of rest, most can fully recover. However, a minority of patients may develop symptoms after concussion such as headache, dizziness, fatigue, anxiety, insomnia, sensitivity to sound and light, difficulty concentrating, memory decline, slowed thinking, irritability, or depression. These symptoms are medically known as post-concussion syndrome. This type of headache is fluctuating in nature and often worsens when the patient lies flat, engages in physical labor, drinks alcohol, or feels stressed or excited; symptoms typically improve with rest.