Frontal Lobes of the Brain: Function, Lesson & Quiz

  • Lesson
  • Quiz
  • Like?
Taught by

Kelly Robson

Kelly has taught High School Science and Applied Communications. She holds an Education Specialist Degree in Ed. Leadership.

A man can get a 1.25-inch diameter iron rod to shoot through his brain and survive. Well, while his life was spared, his personality was changed forever. This event helped scientists to learn about the functions of the frontal lobes of our brains. This lesson will go through these functions and some of the cases that led to the different discoveries.

We also recommend watching Cerebrospinal Fluid in the Brain: Functions & Production and Early Brain Development: Major Parts & Functions


The frontal lobes are located in the anterior of the cerebral cortex. In other words, they are located in the front of the brain. The frontal lobes have a lot to do with personality and how we act.

The frontal lobe is located just behind the forehead in the front part of the brain.
Frontal lobe

Imagine someone makes a mistake and he takes his hand to his forehead and says, 'Oh, no. What did I do?' He's actually putting his hand above the part of the brain that probably made the wrong decision - the frontal lobes.

It may be subconscious, but people put their hand on their foreheads when they are trying to use their frontal lobes to problem solve.
Hand on Forehead

How Do They Know?

To figure out what each part of the brain does scientists of all disciplines look at the brains of patients with disabilities and those without and compare them to each other. Patients who suffer from a traumatic brain injury give scientists great insight to the functions of the brain. Scientists look at the abilities of the person before and after the trauma, then examine the brain through MRIs, CAT scans, and many other tests.

When it comes to traumatic brain injuries, the frontal lobes are on the front line. They are the most vulnerable part of the brain due to their placement right up front just behind your forehead. Along with the location of the brain, the large size of the frontal lobes also makes it vulnerable to trauma. Due to both the size and location, the frontal lobe is the most commonly injured area affected by mild to moderate brain trauma. It is this magnitude of trauma that allows for scientists to understand so much about the functions of the frontal lobes.

Frontal Lobe Function

The frontal lobes are very large and they have been attributed to many functions. Some of these functions include:

  • Motor functions
  • Planning
  • Reasoning
  • Higher-order thinking
  • Judgment
  • Impulse Control
  • Memory
  • Spontaneity
  • Language
  • Social and Sexual Behavior

There are three divisions of the frontal lobes. One division is the prefrontal cortex, which is where personality expression and planning of complex cognitive behaviors occur. In other words, the prefrontal cortex is where you do your thinking and acting. It is where your personality and imagination come from. The other two are a little less complex. The premotor & motor divisions are filled with nerves that control voluntary muscle movements.

Damage and Function

Since there has been a large number of cases of damage to the frontal lobes scientists have a lot of information on what the frontal lobes do. For instance, patients who have damage to their frontal lobes showed a loss of spontaneous facial expressions. So, even if they were surprised they may not show it. Picture somebody who just got a face full of Botox and isn't able to move his or her facial features. This is what a person who has damage to their frontal lobe may look like when they should be looking afraid, like in the image below.

A person with damage to the frontal lobes may not show fear through facial expressions like the boy in this image is doing.

Patients with damage to their frontal lobes also had even more specific changes in how they functioned. Patients who had lesions (bruises or bad spots) on the left side of the frontal lobes spoke fewer words after the damage than they did before. Those who had lesions on the right side of the frontal lobes spoke more excessively than they did before the damage.

One of the most common symptoms of damage to the frontal lobes was a patient's ability to take cues from his or her environment. Have you ever had that person who just kept talking and talking and talking even though nobody was paying attention? The people around him or her may be yawning or even put their heads down, but the person just keeps going and going. Well, the person doing all of this talking is not taking the cues from the people in his or her environment. He or she is not reacting to the cues given to him or her appropriately.

A person with damage in the frontal lobes may not be able to pick up on environmental cues.
Sleeping students

Other examples and actions of people with damage to their frontal lobes do not handle risk-taking properly. They may be non-compliant with rules. As stated above, they are not good with taking social cues from their environment.

Phineas Gage

The most dramatic change a person can go through with damage to their frontal lobes is the change in social behavior. The most famous case of this dramatic change is the case of Phineas Gage. Gage was a model foreman for a railroad company in 1848. It was on the job as a foreman where Gage was using an iron rod to pack a hole full of explosive powder. The pole was 43 inches long, had a 1.25-inch diameter and weighed 13.25 lbs. The powder exploded and sent the rod through Gage's left cheek to his brain; it finally exited through his skull bone. The rod landed several dozen feet away.

Diagram of the entrance and exit of the iron rod through the head and brain of Phineas Gage.
Gage diagram

Gage lost his eyesight in his left eye, but other than a few scars, seemed to be physically fine to outsiders. However, Gage changed. He was no longer the role model foreman and friend. He now went around offending people with vulgar profanity and became cold and rude towards his friends and outsiders alike. The railroad would not let him come back to work. In 1860 Gage died at age 36 from seizures.

Phineas Gage portrait post-accident.
Phineas Gage portrait

Phineas Gage's case is not just famous because of the crazy accident he survived, nor just the profound changes his personality took on. Gage's case is famous because it was the first time scientists were able to observe the connection between personality and brain trauma. These observations were recorded by John Maryn Harlow and led to many discoveries of the different areas of the brain and their specific functions.


The brain is extremely complex and very well organized. There is little room for error or damage. However, when this damage takes place, scientists are able to pinpoint specific functions of our brains. The functions of the frontal lobes, which are located right behind your forehead in the front of the brain, have many functions. Some of these functions include motor function, judgment, impulse control and more. Most of the functions revolve around personality, imagination, thinking, and acting. They serve many purposes, and that is probably why the frontal lobes are so large in size. While the large size allows for the lobes to have many functions it also makes it vulnerable to damage.

Ace Your Next Test & Improve your Grades

As a member, you'll get unlimited access to over 5,000+ video lessons in Math, English, Science, History, and more. Plus, get practice tests, quizzes, and personalized coaching to help you succeed. Learn More

Start your free trial to take this quiz
As a premium member, you can take this quiz and also access over 8,500 fun and engaging lessons in math, English, science, history, and more. Get access today with a FREE trial!
Free 5-day trial
It only takes a minute to get started. You can cancel at any time.
Already registered? Login here for access.

  • Anatomy & Physiology Courses
  • Supplemental Lessons
  • Popular Articles

Search Our Courses

Did you like this?
Yes No

Thanks for your feedback!

What didn't you like?

What didn't you like?

Education Portal Video Lessons

The smarter way to study Short videos, Real results
  • More affordable than tutoring
  • All major high school and college subjects
  • Unlimited access to all 8,500+ video Lessons
  • Study on your own schedule
Try it Free