Clues From Epilepsy Patients
The current study employed 16 epilepsy patients who agreed to participate in experiments while undergoing epilepsy surgery at UC San Francisco and California Pacific Medical Center in San Francisco, Stanford University in Palo Alto and Johns Hopkins University in Baltimore.
This is the first step in looking at how people think and how people come up with different decisions how people basically behave, said Shestyuk, who recorded from the first patient 10 years ago. We are trying to look at that little window of time between when things happen in the environment and us behaving in response to it.
Once the electrodes were placed on the brains of each patient, Shestyuk and her colleagues conducted a series of eight tasks that included visual and auditory stimuli. The tasks ranged from simple, such as repeating a word or identifying the gender of a face or a voice, to complex, such as determining a facial emotion, uttering the antonym of a word or assessing whether an adjective describes the patients personality.
This persistent activity, primarily seen in the prefrontal cortex, is a multitasking activity, Shestyuk said. fMRI studies often find that when a task gets progressively harder, we see more activity in the brain, and the prefrontal cortex in particular. Here, we are able to see that this is not because the neurons are working really, really hard and firing all the time, but rather, more areas of the cortex are getting recruited.
An Adult Brain Weighs About 3 Pounds
The cerebrum makes up 85% of the brains weight, and the brain makes up about 2% of a humans body weight. The texture of the brain is like a firm jelly. The heaviest normal human brain weighed 4.43 pounds. It belonged to the Russian Writer Ivan Turgenev. And the smallest brain, just 2.41 pounds, belonged to a woman.
What Happens In My Brain When I Am Learning
Your brain is primarily composed of about 85 billion neurons, which is more than the number of stars you can see with the naked eye in the night sky. A neuron is a cell which acts as a messenger, sending information in the form of nerve impulses to other neurons . For example, when you are writing, some neurons in your brain send the move fingers message to other neurons and this message then travels through the nerves all the way to your fingers. The electrical signals that are communicated from one neuron to another are therefore what allows you to do everything you do: write, think, see, jump, talk, compute, and so on. Each neuron can be connected with up to 10,000 other neurons, leading to a large number of connections in your brain , which looks like a very dense spider web .
- Figure 1 – Figure illustrating two neurons that are connected.
- Figure 2 – Figure illustrating the very large number of connections between neurons.
- Figure 3 – Figure illustrating the analogy of the trail in the forest.
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How Does The Brain Connect To The Rest Of The Body
You can’t understand what the brain does without knowing about the spinal cord. The spinal cord is an extension of the brain that runs down the middle of the back. The spinal cord is about 44 cm long in adults. It is protected by 33 bones called vertebrae. The brain and the spinal cord together are called the central nervous system. The central nervous system is one part of the nervous system. The rest, mostly nerves, is called the peripheral nervous system.
What Are The Effects Of Meth Use And Abuse
- Increased neuronal death: The use of methamphetamine is associated with decreases in the number of neurons in the CNS. The ability of the CNS to regenerate these neurons is limited, and in many cases, the loss of neurons cannot be recovered. The body of evidence indicates that chronic use of methamphetamine can result in diffuse brain damage that occurs via neuronal death. Neuronal death occurs in a number of areas of the brain as a result of meth abuse that include but are not limited to:
- The hippocampus: a crucial structure for the ability to remember and learn new information
- The striatum: a structure in the subcortical areas of the brain that is crucial in movement and certain aspects of directed attention
- The parietal cortex: a structure that is involved in being able to visualize objects in space and in the memory of nonverbal material
- The frontal and prefrontal cortex: areas of the brain that are crucial in human cognition, particularly in reasoning, complex attention, problem-solving, and the inhibition of behaviors that might be damaging
- A number of subcortical structures: including the basal ganglia, the reward center, the limbic system, and others
- The cerebellum: controls various aspects of movement and is involved in a number of cognitive functions
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How Much Does A Human Brain Weigh
The human brain weighs about 3 lbs. and makes up about 2% of a human’s body weight. On average, male brains are about 10% larger than female brains, according to Northwestern Medicine in Illinois. The average male has a brain volume of nearly 78 cubic inches , while the average female brain has a volume of 69 cubic inches . The cerebrum, which is the main part of the brain located in the front area of the skull, makes up 85% of the brain’s weight.
Structure Of The Brain
The cerebrum has a right half and a left half, known as the right and left hemispheres. The two hemispheres are connected via a thick bundle of nerve fibers called the corpus callosum. Each hemisphere is made up of six areas that have different functions. The cerebrum controls movement and processes sensory information. Conscious and unconscious actions and feelings are produced here. It is also responsible for speech, hearing, intelligence and memory.
The functions of the two hemispheres are to a great extent different: whereas the left hemisphere is responsible for speech and abstract thinking in most people, the right hemisphere is usually responsible for spatial thinking or imagery. The right side of the brain controls the left side of the body, and the left side of the brain controls the right side of the body. This means that damage to the left hemisphere due to a stroke, for example, can lead to paralysis on the right side of the body.
The left cerebral cortex is responsible for speech and language. The right cerebral cortex supplies spatial information, such as where your foot is at the moment. The thalamus provides the cerebrum with sensory information from the skin, eyes and ears, as well as other information. The hypothalamus regulates things like hunger, thirst and sleep. Together with the pituitary gland, it also regulates the hormones in your body.
The cerebellum coordinates movements and is responsible for balance.
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Facts About The Brain
The brain is a very complex part of your body. It has the ability to send and receive a large amount of information. Because of this, there are still many mysteries about the human brain. Here are some quick facts to help you understand the most complicated organ in your body.
What’s The Difference Between The Left Brain And Right Brain
The human brain is divided into two hemispheres, the left and right, connected by a bundle of nerve fibers called the corpus callosum. The hemispheres are strongly, though not entirely, symmetrical. Generally, the left brain controls the muscles on the right side of the body, and the right brain controls the left side. One hemisphere may be slightly dominant, as with left- or right-handedness.
The popular notions about “left brain” and “right brain” qualities are generalizations that are not well supported by evidence. However, there are some important differences between these areas. The left brain contains regions that are involved in language production and comprehension and is also associated with mathematical calculation and fact retrieval, Holland said. The right brain plays a role in visual and auditory processing, spatial skills and artistic ability more instinctive or creative things, Holland said though these functions involve both hemispheres. “Everyone uses both halves all the time,” he said.
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Right Brain Left Brain
The cerebrum is divided into two halves: the right and left hemispheres They are joined by a bundle of fibers called the corpus callosum that transmits messages from one side to the other. Each hemisphere controls the opposite side of the body. If a stroke occurs on the right side of the brain, your left arm or leg may be weak or paralyzed.
Not all functions of the hemispheres are shared. In general, the left hemisphere controls speech, comprehension, arithmetic, and writing. The right hemisphere controls creativity, spatial ability, artistic, and musical skills. The left hemisphere is dominant in hand use and language in about 92% of people.
Your Brain Has Three Main Jobs
Managing your unconscious or ‘automatic’ functions, such as heartbeat, breathing, digestion and control of body temperature.
It’s this third job that we’re particularly interested in as this is where your thinking skills come in.
Your Brain And Your Senses
Some areas of the cerebral cortex are important for thinking and reasoning, some for voluntary movements and speech. There are also areas for your senses. You see, hear, smell, taste and feel because of your brain. Your sense organs fingers, ears, eyes, nose, and tongue gather information about your surroundings and send this information through sensory neurons to special areas in the cerebral cortex. Visit Lobes of the Brain to take a closer look at where the different kinds of sensory signals go to in the cerebral cortex.
Some parts of the body such as your hands and lips have more sensory neurons than other parts. They are for detecting touch, pressure, roughness, smoothness, dry, wet, cold, hot, and pain. This body map, called an homunculus, shows you how much of the cerebral cortex is responsible for processing touch receptor information. And here’s some additional information about your senses.
Our Science TrekFive Senses site has more information.
The Human Brain Looks Suspiciously Like The Universe And Thats Freaking Me Out
When you compare the neurons in the human brain to the cosmic web of galaxies, they look suspiciously the same
And when scientists compare the two structures numerically, the similarities become even more astounding, as if we were all living in one big simulation after all. And that freaks me out!
Lets Talk About Some Big Differences
Now for the flip side on comparisons of the feline and the human brain and sensory system lets discuss a few differences.
Cats whiskers, which humans are obviously not blessed with, are a vital part of the cats sensory mechanism. Those whiskers may look like just a batch of hair, but they are rooted deeply in follicles surrounded by muscle tissue thats rich in sensory cells and nerves connected to part of the cats brain all of which make them important hairs to the cat.
The main function of the whiskers is to be a sort of scanning system. They can detect objects before the cat actually touches them. The slightest air movement will vibrate the whiskers and will send important signals to the brain.
The human reaction to catnip is definitely different from that of a cat. According to Scientific American magazine, human brains are physiologically different from cats brains in this way catnip does not get humans high.
What Are The Major Areas Of The Brain And What Do They Do
|The cerebrum is the largest part of the brain the outer part is called the cerebral cortex.||The cerebellum is about the size of a pear.||The brain stem is located at the bottom of the brain, above the neck, where it connects the brain to the spinal cord.|
|Divided into 2 parts called the right and left hemispheres.||Tucked under and behind the cerebrum.||Divided into three parts: Medulla, Pons, and Midbrain.|
|Responsible for: thinking, senses, producing and understanding language, memories, eating, emotions, body temperature, drinking, sleeping, hormones.||Controls muscle movement, balance, coordination.||Responsible for automatic survival functions such as breathing, heartbeat, and digestion, as well as reflexes such as sneezing, swallowing, and coughing.|
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How Hungry Are Our Brains
Despite the fact that the human brain is not a very large organ, its functioning requires a whole lot of energy.
Although the brain weighs only 2 percent of the body , it alone uses 25 percent of all the energy that your body requires to run per day, Herculano-Houzel explained in a presentation.
And why does the brain need so much fuel? Based on studies of rat models, some scientists have hypothesized that, while most of this energy is expended on maintaining ongoing thought and bodily processes, some of it is probably invested in the upkeep of brain cells health.
But, according to some researchers, at first sight, the brain, seemingly inexplicably, uses up a lot of energy during what is known as the resting state, when it is not involved in any specific, targeted activities.
According to James Kozloski, Inactivity correlated networks appear even under anesthesia, and these areas have very high metabolic rates, tipping the brains energy budget toward a large investment in the organisms doing nothing, he writes.
But Kozloskis hypothesis is that no large amount of energy is spent for no reason so why does the brain seem to do it? In fact, he says, it doesnt.
Energy spent doing nothing, he says, is actually put toward assembling a map of accumulating information and experiences that we can fall back on when making decisions in our day-to-day lives.
The Universe Is Like A Giant Human Brain Scientists Find
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A new study investigated the differences and similarities between two of the most complex systems in existence, though at entirely difference scales: the cosmos and its galaxies and the brain and its neuronal cells.
They found that while the scale is clearly different, the structure is remarkably similar. In some cases, the two systems seemed more similar to each other than they did to the parts that make them up.
It suggests that vastly different physical processes can lead to very similar complex and organised structures.
For example, the human brains works because of the network of nearly 70 billion neurons that together make it up. The universe is thought to have at least 100 billion galaxies.
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What Is The Gray Matter And White Matter
Gray and white matter are two different regions of the central nervous system. In the brain, gray matter refers to the darker, outer portion, while white matter describes the lighter, inner section underneath. In the spinal cord, this order is reversed: The white matter is on the outside, and the gray matter sits within.
Gray matter is primarily composed of neuron somas , and white matter is mostly made of axons wrapped in myelin . The different composition of neuron parts is why the two appear as separate shades on certain scans.
Each region serves a different role. Gray matter is primarily responsible for processing and interpreting information, while white matter transmits that information to other parts of the nervous system.
What Does A Persons Brain Look Like When Theyre High
Marijuana enthusiasts know that being under the influence will change your perception of self and the world around you. So even though regular users might not think itâs too bad of an idea to jump behind the wheel stoned or possibly light up on the road, this 2013 study published in the open-access journal PLOS One suggests that THC changes your perception and attention so much that it can be difficult or dangerous to drive.
The study shows the levels of brain activity in people who are performing a âvisuo-motor tracking taskâ that simulates the cognitive processing and visual recognition a person would use to drive.
There are a lot of studies that show the inner workings of the brain of a person who uses marijuana, but there arenât too many that actually show what it looks like while theyâre stoned.
In this case, people who smoked marijuana and attempted the exercise showed a decrease in blood flow to their anterior insula, dorsomedial thalamus, and striatum compared to people who smoked placebo weed.
Now if you recall, the insula is associated with initiating actions based on physical state, and the striatum is associated with reward and decision-making. The dorsomedial thalamus is involved with memory and cognition.
While high, you might not realize that your dog is eating your Fritos, or, more dangerously, maybe not react in time to see a pedestrian running in front of your car.
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