Kobe,

Welcome to NeuroTalk. This twitching is very common. In fact, many people who have never suffered a brain trauma have such twitching. The most common time is that point just as the person transitions from awake to asleep.

There was a post about this a couple weeks ago. I'll try to find it.

Here are my comments.

A hypnagogic jerk is an involuntary muscle spasm that occurs as a person is drifting off to sleep. The phenomenon is so named in reference to the hypnagogic state — the transitional period between wakefulness and sleep. Hypnagogic jerks, are also commonly known as hypnic jerks or sleep starts.

Hypnic Jerks - The Reason Why We Twitch Before Falling Asleep