7.8 What is Parallel Processing? – Definition & Model
You’re alive today because your brain is able to do a few things at the same time. We’re not talking about multi-tasking, like folding laundry and talking to friends on the phone at the same time. We’re referring to parallel processing, the brain’s ability to make sense of several different incoming stimuli at the same time.
Think about driving your car down the street. Your brain is constantly taking in information through your senses – what you see, hear, and sometimes feel and smell – to determine how to safely go to Taco Bell. This all happens at the same time; you don’t first notice the shape of the stop sign, then the color, then the letters, then the message behind the sign. Instead, your brain takes all these stimuli in at once, along with lots of other background information (like a dog getting ready to run into the road), processes it, and sends signals to your muscles telling them to step on the brake.
We don’t just experience driving in this way. Nearly every moment of our lives is characterized by taking in many forms of information. When you were very young, you were comforted by the softness of the blankets wrapped around you, the sound of your parents’ voices, the smell of your familiar surroundings, and the taste of mashed carrots – all at once.
All of these stimuli are processed at the same time and are stored as memories that hold specific meanings. If you grew up in a home where your mother baked pies every night for dessert, you will likely associate that smell with a feeling of safety, warmth, or other sensations. Our personalities, behaviors, and reactions to the outside world are shaped by how our senses take in experiences and process them. How does this work? Let’s take a look.
How It Works
We use our senses to take in information, which is then sent to the brain for processing. When you sniff a rose, your nose sends the information about this sweet smell to a series of channels that divide these signals into similar pieces. This happens so the information sent to your brain can be bundled into small packages the brain can understand. You send a ‘rose smell’ signal that gets put into the brain as a specific thing, such as ‘sweet.’ But your body isn’t just processing the smell of the rose; maybe while smelling the rose, you’re also hearing and feeling a soft breeze blow through the trees and seeing a field of bright red and yellow flowers. All these parallel signals need to be put together inside your cortex, the part of your brain responsible for thoughts and action, to give you an understanding of what you’re experiencing.
The entire process can be complicated and requires an understanding of many different brain and body systems. Many things are going on at the same time as your eyes and brain are working together to notice and understand the details of what is being experienced.
Processing and Vision
Like we talked about, parallel processing isn’t just related to vision. However, vision does play an especially important role, as our brains take in and group information into colors, shapes, depth, and motion. Like we saw in the example of the stop sign at the beginning of the video, parallel processing allows our brains to input all the information it sees related to the sign: its red color, octagon shape, written word, and distance of the sign.
Glance away from the screen for a second and look at the room around you. Did you notice how your brain saw a lamp or a chair and put all the information together very quickly? Instead of seeing the gray fabric, square seat, wooden legs, and round wheels on the chair, your brain zapped all this input together at the same time, searched for a memory from past data input, and named the word ‘chair.’ If we instead performed these processes one at a time – color, shape, size – we’d probably not exist as a species. Our ancestors would have had a hard time fighting off predators if they saw and processed one thing at a time.
The information we take in from the environment helps us make decisions about our lives. If you’re hungry, and you notice you don’t have food in the pantry, you have several choices, such as going to the grocery store or ordering pizza.
There’s nothing dangerous about deciding whether or not to order pizza. Sometimes, though, we’re faced with decisions relating to our health and well-being. The extended parallel processing model takes a look at how this works by explaining how what you believe to be true, coupled with the emotions you have tied to the belief, drive decisions about events. In other words, how much you feel threatened by an event will drive your decision to act on the event.
Imagine you have a toothache. If it is your first time with this experience, and the pain isn’t too bad, you may choose to take an aspirin and see how things go. However, if your best friend just had her wisdom teeth pulled, and your dentist mentioned that yours were close to coming in during your last visit, you may jump to the conclusion that you need to get back to the dentist pronto before the pain becomes unbearable. The higher the perceived threat, the more quickly your brain processes the information as important, and the more likely you’ll be to react.
Parallel processing happens when our senses take in stimuli from different senses at the same time, and the information is processed and understood all at once. This occurs nearly every moment of our lives; these experiences and our brain’s understanding of them shape memories, beliefs, and personalities. The extended parallel processing model explains that the more threatening information coming into our brains is, the more likely we are to act on it. Parallel processing helps us make sense of our world and keeps us alive and safe.