Worm Skip Edit
The attack of the brain slug will always force the boy to walk left. Usually, if you walk to the right beyond the slug, a short animation will start where the boy itches a bit, and then turns around the other direction. However, if the boy is facing to the left already when the brain slug attaches to his head, he will start walking left immediately instead of itching a few times. This trick is almost frame perfect, as one has to face to the left the moment the brain slug detaches from its nest. This strat can be used at every brain slug in the game.
A correct performed turn around saves approximately 2 seconds.
Basic Brain Slug Movement Edit
While under the influence of a brain slug, you will be forced to walk into one and the same direction. While you can't change the direction, using the directional inputs still increase or decrease the boy's speed. To maximise the speed, press the direction the boy is currently walking to and time your jumps as you usually would, just as without influence of a brain slug.
Press Jump to Turn Faster Edit
If you don't get a Turn Around immediately, you can still minimize the time by pressing and holding the jump button while the boy itches. This also works for the scripted turns that happen when the boy enters a source of light. When walking into light, don't let go of the direction you're currently holding, as it will minimize the time before the animation. Be cautious to not press the button to early, though, since that would perform another jump in the direction the boy was moving before and as such delay the turning. As soon as the boy stops and itches, press and hold the jump button, to break free from this state a little earlier.
Colette Skip Edit
A well known but extremely hard - almost random - way to decrease the affected time of the first brain slug is the Colette Skip. See the page for more info. [LINK -> Colette Skip at "unrecreatable skips"]