Parts Of The Brain Involved With Hearing
When one listens to music or hears someone speak, the brain must process what it has heard . In order to be understood, sounds must first be converted to vibrations in the middle ear and then to electrical impulses in the inner ear. These electrical impulses are then relayed to different sites in the brain for interpretation.
If you are experiencing serious medical symptoms, seek emergency treatment immediately.
How Does The Frontal Lobe Interact With Other Areas Of The Body
Though the frontal lobe is often deemed the seat of consciousness, it cannot think or feel alone. No single brain region can fully control any other region or function without heavy input from the body, other parts of the brain, and the outside world. The frontal lobe is no exception, and works alongside all other brain lobes to coordinate consciousness.
The frontal lobe, like all brain regions, connects with the limbic lobe, which houses brain structures associated with the limbic system. The limbic system controls automatic and primitive reactions, but these reactions are heavily dependent upon emotion and experience. Because the frontal lobe is home to much consciousness, its input into the limbic lobe is vital. For instance, an emotional reaction to a traumatic experience can affect limbic functioning forever, and the memories housed in the frontal lobe may strengthen limbic system reactions over time.
Because the frontal lobe is home to many higher functions, it is especially dependent upon experiences and memories. That means that social interactions, education, and similar experiences heavily affect the functioning of this important brain region. Sensory input also plays a key role, since the frontal lobe relies on memory, previous experience, and information about the surrounding world to judge the potential effects of future actions.
Pituitary Gland Controls Growth
The pituitary gland is very small only about the size of a pea! Its job is to produce and release hormones into your body. If your clothes from last year are too small, its because your pituitary gland released special hormones that made you grow. This gland is a big player in too. This is the time when boys and girls bodies go through major changes as they slowly become men and women, all thanks to hormones released by the pituitary gland.
This little gland also plays a role with lots of other hormones, like ones that control the amount of sugars and water in your body.
Basic Temporal Lobe Function
The temporal lobes are located at the sides of the brain, and can be considered the “middle” region of each brain hemisphere. As a whole, the temporal lobe is the part of your brain in charge of memory storage, the process of hearing sounds, visual recognition of faces and objects, and the use of language. Though this seems like an incredible number of functions for one small part of the brain to command, the temporal lobes are actually more complex than they look; they contain a number of specialized substructures, including the amygdala and auditory cortex, that perform a variety of high-level functions. At the same time, the temporal lobes aren’t the only parts of the brain used in many of these mental processes the frontal and parietal lobes make sense of processed sounds for example, and the hippocampus creates the memories that the temporal lobe then stores and recalls.
Cortical Strokes Vs Subcortical Strokes
Before we dive into the different areas of the brainaffected by stroke, you should know the difference between cortical vssubcortical strokes.
The cerebral cortex/cerebrum is a large part of the brain that includes 4 lobes: the frontal lobe, parietal lobe, occipital lobe, and temporal lobe. Strokes in these regions are known as a cortical strokes.
Aside from the cerebrum, there are subcortical structures thatlie deep within the brain. Strokes in these areas of the brain are also knownas subcortical strokes.
The arteries that supply the subcortical areas of the brain are smaller and more delicate. Subcortical strokes are often hemorrhagic strokes due to the fragile arteries bursting, often from high blood pressure.
There are many differences between cortical and subcortical strokes. For example, cortical strokes often impact higher level functioning; and its uncommon for subcortical strokes to result in language difficulties.
We will discuss other patterns next!
Functions Of The Frontal Lobe
The frontal lobe plays a key role in future planning, including self-management and decision-making.
People with frontal lobe damage often struggle with gathering information, remembering previous experiences, and making decisions based on this input.
Some of the many other functions the frontal lobe plays in daily functions include:
One of the most infamous frontal lobe injuries happened to railroad worker Phineas Gage.
Gage survived after a railroad spike impaled a portion of his frontal lobe. Though Gage survived, he lost his eye and much of his personality.
Gages personality dramatically changed, and the once mild-mannered worker struggled to stick to even simple plans. He became aggressive in speech and demeanor and had little impulse control.
Much of what we know about the frontal lobe comes from case reports on Gage. Those have been called into question since, however. Little is known for sure about Gages personality before his accident, and many stories about him may be exaggerated or false.
The case demonstrates a larger point about the brain, which is that our understanding of it is constantly evolving. Hence, it is not possible to accurately predict the outcome of any given frontal lobe injury, and similar injuries may develop quite differently in each person.
In general, however, damage to the frontal lobe due to a blow to the head, a stroke, growths, and diseases, can cause the following symptoms:
- speech problems
What Does The Left Side Of The Brain Control
The left side of the brain is generally dominant for language and other logical tasks. This side of the brain is also used for math or various calculations, according to the University of Washington. The left side of the brain also controls muscles on the right side of the body. Sensory information from the bodys right side crosses over to the left side of the brain.
The ability to form words primarily lies in the left hemisphere, states the National Institute of Neurological Disorders and Stroke. Both hemispheres are divided into sections, or lobes, which specialize in different functions. The Brocas area, which is found on the left frontal lobe, enables thoughts to be transformed into words.
The left hemisphere of around 95 percent of right-handed individuals and 60 to 70 percent of left-handed persons is dominant for language, explains the University of Washington. The two specific areas of the brain that are important for language are named the Brocas area and Wernickes area.
As most of the signals from the brain to the body and vice versa cross over when reaching the brain, both left and right hemispheres control the opposite side of the body, notes the NINDS. Thus, when the left hemisphere is damaged, the right part of the body is affected. For instance, a stroke in the left hemisphere usually leaves the right arm and leg paralyzed.
How Do We Know All This
Before advanced medical imaging, most of our knowledge came from observing unfortunate patients with injuries to particular brain parts. One could relate the approximate region of damage to their specific symptoms. Brocas and Wernickes observations are well-known examples.
Other knowledge was inferred from brain-stimulation studies. Weak electrical stimulation of the brain while a patient is awake is sometimes performed in patients undergoing surgery to remove a lesion such as a tumour. The stimulation causes that part of the brain to stop working for a few seconds, which can enable the surgeon to identify areas of critically important function to avoid damaging during surgery.
In the mid-20th century, this helped neurosurgeons discover more about the localisation of language function in the brain. It was clearly demonstrated that while most people have language originating on the left side of their brain, some could have language originating on the right.
Towards the later part of the 20th century, if a surgeon needed to find out which side of your brain was responsible for language so he didnt do any damage he would put to sleep one side of your brain with an anaesthetic. The doctor would then ask you a series of questions, determining your language side from your ability or inability to answer them. This invasive test is known as the Wada test, named after Juhn Wada, who first described it just after the second world war.
Brain Areas And Their Functions
The brain is divided into areas which are each responsible for different areas of functioning.
The brain can be divided into three basic units: the forebrain, the midbrain and the hindbrain.
These areas are: Occipital lobe, Temporal lobe, Parietal lobe, Frontal lobe.Cerebral cortex, Cerebellum, Hypothalamus,Thalamus,Pituitary gland, Pineal gland, Amygdala, Hippocampas and the Mid- brain.
The image below indicates where the areas are.
Occipital lobe: This is found in the back of the brain. The area is involved with the brain’s ability to recognise objects. It is responsible for our vision.
Temporal lobe: The temporal lobes are found on either side of the brain and just above the ears. The temporal lobes are responsible for hearing, memory, meaning, and language. They also play a role in emotion and learning. The temporal lobes are concerned with interpreting and processing auditory stimuli.
Parietal lobe: The parietal lobes are found behind the frontal lobes, above the temporal lobes, and at the top back of the brain. They are connected with the processing of nerve impulses related to the senses, such as touch, pain, taste, pressure, and temperature. They also have language functions.
Frontal lobe:It is concerned with emotions, reasoning, planning, movement, and parts of speech. It is also involved in purposeful acts such as creativity, judgment, and problem solving, and planning
The Brain Is Flexible: Neuroplasticity
The control of some specific bodily functions, such as movement, vision, and hearing, is performed in specified areas of the cortex, and if these areas are damaged, the individual will likely lose the ability to perform the corresponding function. For instance, if an infant suffers damage to facial recognition areas in the temporal lobe, it is likely that he or she will never be able to recognize faces . On the other hand, the brain is not divided up in an entirely rigid way. The brains neurons have a remarkable capacity to reorganize and extend themselves to carry out particular functions in response to the needs of the organism and to repair damage. As a result, the brain constantly creates new neural communication routes and rewires existing ones. Neuroplasticity refers to the brains ability to change its structure and function in response to experience or damage. Neuroplasticity enables us to learn and remember new things and adjust to new experiences.
Although neurons cannot repair or regenerate themselves as skin or blood vessels can, new evidence suggests that the brain can engage in neurogenesis, the forming of new neurons . These new neurons originate deep in the brain and may then migrate to other brain areas, where they form new connections with other neurons . This leaves open the possibility that someday scientists might be able to rebuild damaged brains by creating drugs that help grow neurons.
Blood Supply To The Brain
Two sets of blood vessels supply blood and oxygen to the brain: the vertebral arteries and the carotid arteries.
The external carotid arteries extend up the sides of your neck, and are where you can feel your pulse when you touch the area with your fingertips. The internal carotid arteries branch into the skull and circulate blood to the front part of the brain.
The vertebral arteries follow the spinal column into the skull, where they join together at the brainstem and form the basilar artery, which supplies blood to the rear portions of the brain.
The circle of Willis, a loop of blood vessels near the bottom of the brain that connects major arteries, circulates blood from the front of the brain to the back and helps the arterial systems communicate with one another.
Ataxia Caused By Stroke
Stroke is a clot or bleed in any part of the brain. The cerebellum is a less common site for stroke than the cerebrum, but it can still occur there.
A clot or bleed in the cerebellum can cause the following:
Treating the stroke might resolve the ataxia. Occupational and physical therapy can help manage any permanent damage.
Ventricles And Cerebrospinal Fluid
The brain has hollow fluid-filled cavities called ventricles . Inside the ventricles is a ribbon-like structure called the choroid plexus that makes clear colorless cerebrospinal fluid . CSF flows within and around the brain and spinal cord to help cushion it from injury. This circulating fluid is constantly being absorbed and replenished.
There are two ventricles deep within the cerebral hemispheres called the lateral ventricles. They both connect with the third ventricle through a separate opening called the foramen of Monro. The third ventricle connects with the fourth ventricle through a long narrow tube called the aqueduct of Sylvius. From the fourth ventricle, CSF flows into the subarachnoid space where it bathes and cushions the brain. CSF is recycled by special structures in the superior sagittal sinus called arachnoid villi.
A balance is maintained between the amount of CSF that is absorbed and the amount that is produced. A disruption or blockage in the system can cause a build up of CSF, which can cause enlargement of the ventricles or cause a collection of fluid in the spinal cord .
Where Is The Auditory Cortex
A coronal section of the left hemisphere, showing the primary auditory cortex as well as surrounding auditory regions .
The auditory cortex is found in the temporal lobe. Most of it is hidden from view, buried deep within a fissure called the lateral sulcus. Some auditory cortex is visible on the external surface the brain, however, as it extends to a gyrus called the superior temporal gyrus.
The auditory cortex can be subdivided into multiple regions, although there is still some question about the most appropriate way to create those subdivisions in the human brain. There is general agreement, however, that the auditory cortex consists of a primary areawhich is often referred to as the core regionas well as multiple non-primary areas.
The primary auditory cortex in humans is hidden within the lateral sulcus on a collection of gyri known as Heschls gyri . The precise location of the primary region in humans is variable, however, as is the arrangement of Heschls gyri . For example, in some individuals the primary auditory cortex seems to occupy one Heschls gyrus, while in others it may extend past that gyrus into a neighboring sulcus .
The Biggest Part: The Cerebrum
The biggest part of the brain is the cerebrum. The cerebrum is the thinking part of the brain and it controls your voluntary muscles the ones that move when you want them to. So you need your cerebrum to dance or kick a soccer ball.
You need your cerebrum to solve math problems, figure out a video game, and draw a picture. Your memory lives in the cerebrum both short-term memory and long-term memory . The cerebrum also helps you reason, like when you figure out that youd better do your homework now because your mom is taking you to a movie later.
The cerebrum has two halves, with one on either side of the head. Scientists think that the right half helps you think about abstract things like music, colors, and shapes. The left half is said to be more analytical, helping you with math, logic, and speech. Scientists do know for sure that the right half of the cerebrum controls the left side of your body, and the left half controls the right side.
Vomiting: Persistent And Inexplicable
If you feel like throwing up or are actually throwing up without any problem in your digestive system, see if they occur with headaches or a problem in your vision.
Persistent vomiting or nausea, without any apparent reason, especially in the morning or when you change your position, can be a sign of a brain tumor. Vomiting is often a result of raised pressure inside the skull, which is why movement triggers it.
In a study on 111 brain tumor patients with primary and metastatic tumors, 40% complained of vomiting and nausea.
This means that vomiting is a common sign across the various stages of brain tumor. It is usually thought to be a symptom of a tumor in the cerebellum. However, if it presents without other symptoms, we often misdiagnose vomiting as a symptom of a problem in the digestive system.
What Controls The Bodys Balance
In addition to the cerebellum, two crucial structures in maintaining balance are the inner ear and the vestibular cranial nerves.
Located in the inner ear, the vestibular system provides your brain with the necessary information for motion, head position, and spatial orientation.
It also plays a role in your motor functions that are involved in keeping your balance, stabilizing your head and body during movement, and also helps maintain your posture.
The vestibular system absolutely essential for your bodys equilibrium, thus making it a vital part aiding you in balance.
Damage to any part of the brain related to balance isnt inherently life-threatening, however, it can result in a jerky, and uncoordinated movements if the damage is severe.
Relationship To The Auditory System
The auditory cortex is the most highly organized processing unit of sound in the brain. This cortex area is the neural crux of hearing, andin humanslanguage and music. The auditory cortex is divided into three separate parts: the primary, secondary, and tertiary auditory cortex. These structures are formed concentrically around one another, with the primary cortex in the middle and the tertiary cortex on the outside.
The primary auditory cortex is tonotopically organized, which means that neighboring cells in the cortex respond to neighboring frequencies. Tonotopic mapping is preserved throughout most of the audition circuit. The primary auditory cortex receives direct input from the medial geniculate nucleus of the thalamus and thus is thought to identify the fundamental elements of music, such as pitch and loudness.
An evoked response study of congenitally deaf kittens used local field potentials to measure cortical plasticity in the auditory cortex. These kittens were stimulated and measured against a control ) and normal hearing cats. The field potentials measured for artificially stimulated CDC were eventually much stronger than that of a normal hearing cat. This finding accords with a study by Eckart Altenmuller, in which it was observed that students who received musical instruction had greater cortical activation than those who did not.
Memory Loss: Recalling Or Registering Information
You may forget objects, people, places, or events you knew before you got the tumor or forget most information about events that happened ever since you got the tumor .
A brain tumor, especially in the frontal and the temporal lobes, may affect your memory of objects, people, places, or events in your life. The inability to recall any such information that you knew before you had the brain tumor is known as retrograde amnesia.
You might also not be able to remember anything that happened since the brain tumor developed. This inability to process new information is known as anterograde amnesia. Sadly, memory loss may be an effect of the treatment as well.
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.
Functions Of The Brain
The human brain is magnificent and complex. The brain is made up of many parts, each with a specific and important function. It controls our ability to balance, walk, talk, and eat. It coordinates and regulates our breathing, blood circulation, and heart rate. It is responsible for our ability to speak, to process and remember information, make decisions, and feel emotions. Every brain is unique, ever-changing, and extremely sensitive to its environment.
The brain is divided into functional sections, called lobes:
- Frontal Lobe
- Temporal Lobe
Each lobe has an important and specific function, detailed below.
The functional sections of the brain are also categorized by side the right side and the left side. If you split the brain down the middle into two equally-sized parts, they are not the same and do not carry the same functions. The right side of the brain controls the left side of the body, while the left side of the brain controls the right side of the body. Each side is responsible for different functions, and general patterns of dysfunction may occur depending on the side of the brain sustaining an injury.
The traits of each side are detailed below:
Where Is The Frontal Lobe Located
Neuroscientists have traditionally divided the brain’s cerebrum into four lobes: the frontal, parietal, occipital, and temporal. The cerebrum is the newest part of the brain to have evolved, and houses most higher functions, such as conscious thought, morality, memory, and the ability to learn through memorization, deduction, and other complex processes. The frontal lobe plays a key role in this complex set of cognitive functions.
Named for its location, the frontal lobe is situated toward the front of the cerebrum, just behind the forehead and under the frontal skull bones. It sits atop the temporal lobe, in front of the parietal lobe, and apart from the occipital lobe, with portions of the limbic systemsometimes called the limbic lobe crossing all four brain lobes, including the frontal lobe.
The central sulcus separates the frontal and parietal lobes, with the lateral sulcus separating the frontal and temporal lobes.
Left Hemisphere Vs Right Hemisphere Stroke
Along with different lobes and structures, the brain is alsodivided into two halves, called hemispheres.
Aside from the different areas of the brain that can beaffected by stroke, its also helpful to look at difference between the twohemispheres.
Generally speaking, the left hemisphere controls languageand logical reasoning; while the right hemisphere is believed to control creativityand object recognition. This is why language difficulties after stroke areoften associated with left hemispherestrokes.
Furthermore, each hemisphere controls movement on the opposite side of the body. Usually, a left hemisphere stroke will cause motor impairments on the right side of the body; while a right hemisphere stroke will likely impair the left side of the body.
When stroke impacts both hemispheres, its possible tosustain motor impairments on both sides of the body.
Other Key Parts Of The Brain
Ventricular System The brain is not a solid organ. Instead, there are fluid-filled cavities within the brain called ventricles. The ventricles provide nourishment to the brain. The ventricular system produces and processes cerebrospinal fluid, a clear, watery substance flowing around the brain to cushion and protect it.
Cranial NervesThe brain also contains 12 pairs of cranial nerves. Each is responsible for specific body functions.
- Olfactory nerve: Sense of smell
- Optic nerve: Vision
Clumsiness: Loss Of Balance And Coordination
Loss of balance, lack of coordination in the limbs, trouble swallowing, and numbness or weakness in one side of the body can be because of brain tumors.
If you are finding it difficult to maintain your balance while walking or having difficulty coordinating your hands and legs, it might be a symptom of brain tumor. This might be caused by a tumor in the cerebellum, the primary motor cortex, or the parietal lobe, all of which are responsible in different ways for the coordination of movements. A brain stem tumor that affects hearing can also contribute to loss of balance.
If your clumsiness can be attributed to numbness or weakness in one side of your body, it might be caused by a tumor in the parietal lobe. As the brain stem and the frontal lobe control muscular movements related to swallowing and speaking, respectively, patients also have trouble with these activities if they get tumors in these areas.