There are two ways people can perceive the world, through bottom up processing or top down processing. Learn about bottom up processing and how we apply it in the real world.
A human’s senses help them perceive the world around them. This way, we can identify sounds, smells, taste, what we see, and physically feel. While your brain can process data from these senses individually, how we perceive them helps us act on them. In fact, a person’s perception can use them as clues to identify them as a whole concept.
For instance, let’s say you smell bread baking and see loaves of bread in a store window. You might conclude that you’re in front of a bakery. This type of perception is called bottom up processing, which is one of the two types of perception in humans. The other type is top down processing.
Bottom Up Processing vs. Top Down Processing
The easiest way to explain these two types of perception is as follows, When you process things bottom up, you start with the data you receive from your senses. Bottom up perception holds that we use our senses to perceive information and process it in our brains. These include taste, touch, sight, smell, and hearing.
Top down processing involves cognition. The knowledge you have allows the brain to perceive something based on what we already know. For instance, if you receive a text message that reads: “C U L8r,” you know it means “see you later.” That’s because you apply what you already know about what you’re seeing.
Bottom Up Processing Starts with Perception
Everything we perceive begins with the bottom up processing approach because it is based on our senses. Without being able to see the text, we wouldn’t know what it says. However, if you can see it, then your brain can interpret it based on things you’ve learned. Let’s take a blind person for example. If their smartphone reads the above text message as it’s received, then their hearing allows them to interpret the message.
Most people draw conclusions based on what they perceive with their senses. For instance, what if you’re alone in your house and you hear a strange noise? You may think someone is trying to break into your home. Let’s say you decide to investigate the noise and find a box of cat food on the floor near the kitchen counter. You may then conclude that your cat knocked it down after smelling the food.
When the senses perceive something, it stimulates the brain, which will react with emotions to what it senses. So, if you see cat food on the floor, you might feel annoyed that your cat tipped over the box. On the other hand, you may feel relieved that no one’s breaking into your house.
Your perception also helps you turn what you sense into actions, For example, you may scold your cat, and then put the box of food away. Also, you may check to make sure you’ve locked your doors and windows. Sometimes we don’t even process this information consciously. This is often referred to as intuition.
Top Down Processing Starts with Cognition
Top-down processing is more based on patterns than on conclusions after you receive sensory information. Take the above text message for example. When you see the combination of letters and the number in “C U L8r,” your mind sees the pattern. Since you know what the letters and number sound like, your mind translates it to “see you later.”
Or, when you hear the opening chords of a song you like, your brain recalls the rest of the song. While this starts with your sense of hearing, it’s your brain that processes the notes. It then tells you the name of the song you’re about to hear. This is another example of top-down processing.
The brain reacts so quickly that you can think of the song almost instantly when you hear the first strands. For example, let’s say you’re in a forest and hear crackling wood while seeing and smelling smoke. It won’t take long for your brain to tell you there’s a forest fire. You then likely start running away from it as fast as you can.
Gibson’s Bottom Up Processing Theory
In 1966, a psychologist by the name of James Gibson theorized that bottom up perception was direct, or innate. In other words, we are born with this ability and don’t have to learn it. This theory is sometimes called the “Ecological Theory.” This theory says you can explain perception based on the environment in which you find yourself.
Bottom up perception allows us to survive in unfamiliar environments. Because our senses provide basic information, our brains can react quickly. For example, let’s say you’re in a forest and hear crackling wood while seeing and smelling smoke. It won’t take long for your brain to tell you there’s a forest fire. You then likely start running away from it as fast as you can.
Gibson made the argument that perception is a bottom-up process because the brain reacts to your senses. Take an optic array — patterns of light — for example.
With Gibson’s theory, once your eyes transmit the optic array, your brain receives all the information needed to understand it. The information perceived from the array is direct, or innate because it requires no further evaluation. Even if the array moves or the light intensity changes, we can still interpret it. That’s because we already have an innate and stable concept of how it works.
His theory translates to “what you see is what you get.” You don’t need to evaluate anything. The information you get alone is enough to help you survive in new situations.
Gregory’s Top Down Processing Theory
On the other hand, a psychologist by the name of Richard Gregory claimed that perception is a top-down process. The information people learn and their experiences help them to perceive the world around them. He claimed by the time data from our senses reaches the brain, about 90% of it is lost.
Losing this information means we need to rely on our experiences and what we see. For instance, if you see a tall rectangle with a knob on it, your brain perceives it as a door. That’s because, in past experiences, tall rectangles with knobs on them turn out to be doors. By just depending on visualization, a person may not know what the rectangular object is. They may need to further investigate it by turning the doorknob.
Watch: Top Down vs. Bottom Up Processing.
How We Use Bottom-Up Processing Perception
Therapists can use a bottom-up approach to help patients with mental health issues or physical impairments. Based on experience, a psychologist can take cues from how a patient reacts to questions or when describing their issues. They can then determine what course of treatment to pursue.
For instance, if a topic makes a patient look queasy or nervous, the therapist knows this area needs work. They may delve further into these topics to see what traumas they experienced that triggered their physical reactions.
Occupational therapists also often use a bottom up processing approach. For example, to help patients regain motor skills lost due to an accident or illness. Bottom-up assessments have been the standard for occupational therapists for decades when first meeting new clients.
These bottom up assessments can help evaluate a new client’s skill level or how well they can perform occupational tasks. This approach focuses on evaluating the body’s functions or structure to see how well a client can perform physical tasks they used to perform.
An example of a bottom-up assessment is Peabody’s Developmental Motor Scales. This is used to evaluate a child’s ability to grasp objects. The assessments include having children stack blocks or place coins in a box. This helps a therapist see how well they could grasp and move objects. In turn, these assessments help therapists evaluate motor skills to see if a child is where they should be developmental.
Experts also sometimes use a bottom-up processing approach in criminal cases to profile offenders. For example, Professor David Canter of the International Centre for Investigative Psychology created a bottom up approach to profiling sexual offenders. It uses evidence from the scene of the crimes instead of profiling perpetrators by using typologies of past offenders.
The main factors of the bottom-up approach to criminal profiling are:
- Interpersonal Coherence
- The significance of Time and Place
- Forensic Awareness
Canter’s theory includes five key variables to try to identify patterns of behavior between similar offenses to create profiles of the perpetrators. He came up with these key variables by examining 66 sexual assault cases. They are as follows.
- Attempted intimacy with victims.
- Sexual behavior.
- Obvious violence or aggression.
- Impersonal interactions.
- Criminal behaviors and intentions.
These factors have helped identify those who’ve committed two or more offenses. It also helps identify changes in behavior patterns that could that could indicate that similar crimes were committed by different people.
Bottom-up processing to determine offender profiles has proven more reliable and objective than the top-down approach. While there are still questions and concerns whether top down or buttom up is better, both types of processing have their places when applied to mental health or occupational therapies.
Featured image: CC0 Public Domain Skitterphoto via Pixabay.