Arriving home one afternoon after a long day, I found my roommate seemingly couch-locked, eyes fixated on the newest episode of Atlanta. He was surrounded by the residual haze from what I could only assume was hours worth of blunts and bong rips.

“Enjoying your day off?” I asked. His lack of a response coupled with his open-mouthed gaze focusing on Donald Glover alluded that he was in the zone. It wasn't until I sat on the recliner opposite him, his concentration finally broke.

“Hey man; I didn’t even notice you come in,” he said, eyes still stuck on the television.

Knowing him and his tolerance for weed, I figured his unreactive state had something to do with his fixation on the screen. He was a zombie.

What’s really going on in our brains when we watch television?

That complex mush inside our heads has something like a specific ‘mode,’ which it enters once focus turns to the tube. One study by Herbert Krugman, dating all the way back to 1969, concluded that even under a minute of watching T.V. can cause the brain to switch from primarily using beta waves (which are involved in active or logical thought) to using alpha waves (commonly associated with the “idling” of the brain).

Alpha waves typically manifest when we’re trying to fall asleep, or while we slip in and out of consciousness during a Chemistry lecture. Relaxed, but still awake. For those of us who didn’t waste four years of our lives getting a BS in Psychology, this means the areas of the brain associated with active and logical thought are not being put to use while watching reruns of Rick and Morty.

Unsurprisingly, this alpha state is exactly where advertisers want our brains to be, since this is when the human brain is most receptive to outside influence. Essentially, companies bank on us going into this semi-hypnotic state while we watch our shows, so they may then bombard us with suggestive information during the commercial breaks — increasing their chance of selling something to the viewers.

As we lay to rest, our brains enter that same alpha state and we begin to process the information we intake across the day. Here we learn unconsciously, which may explain why all of those catchy commercial jingles get stuck in your head like a coffee stain on a white shirt.

One thing television has long been accused of is being detrimental to one’s ability to focus. When broken down, it’s quite the interesting concept: How does giving a screen our undivided attention for minutes to hours at a time hurt our overall attention span?

According to researchers Michael Smite and Alan Gevins, this all comes down to the nature of the medium itself, flashing images. Whenever we turn on the tube, we expose ourselves to hundreds or even thousands of images being rapidly flashed in front of our eyes, the nature of which coaxes our brains into giving them our attention.

The problem is overstimulation. When humans enter a state of sensory overload, it becomes difficult to focus for the time being. But the effect doesn’t stop there, as shown by findings by Japanese researchers. Repeated overstimulation actually dulls the brain’s response to stimuli in general.

For example, let’s say we’re headed to Coachella for the first time. The large crowds of people may be anxiety inducing at first, the smells of all the sweaty people nauseating, the sounds of so many conversations as well as musical acts going on at once deafening — the wardrobe choices of attendees could be confounding.

However, those acclimated to concerts or music festivals don't experience the event like this. Repeated overstimulation has left them numb to the smells, sights, and sounds of the hustle and bustle around them — what some might consider large crowds may not even phase others.

Television has a similar effect. After watching images quickly flashing and changing faster than what is possible in nature, one might begin to struggle with staring at a static computer screen in order to focus on writing an English paper they’ve been procrastinating on … or keeping at attention through that same Chemistry lecture. Your body now craves movement, something a dull professor or book might not offer.

My roommate, stoned as he may have been, was quite literally in a trance. One that works best for advertisers, detrimental to the rest of us.