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Symptoms of Brain Injury

Any brain function can be disrupted by brain trauma: excessive sleepiness, inattention, difficulty concentrating, impaired memory, faulty judgment, depression, irritability, emotional outbursts, disturbed sleep, diminished libido, difficulty switching between two tasks, and slowed thinking.

Symptoms of Brain Injury

Any brain function can be disrupted by brain trauma and result in excessive sleepiness, inattention, difficulty concentrating, impaired memory, faulty judgment, depression, irritability, emotional outbursts, disturbed sleep, diminished libido, difficulty switching between two tasks, and slowed thinking. Sorting out bonafide brain damage from the effects of migraine headaches, pain elsewhere in the body, medications, depression, preoccupation with financial loss, job status, loss of status in the community, loss of status in the family, and any ongoing litigation can be a formibable task.

The extent and the severity of cognitive neurologic dysfunction can be measured with the aid of neuropsychological testing. Neuropsychologists use their tests to localize dysfunction to specific areas of the brain. For example, the frontal lobes play an essential role in drive, mood, personality, judgment, interpersonal behavior, attention, foresight, and inhibition of inappropriate behavior. The ability to plan properly and execute those plans is known as "executive function." Frontal lobe injury is often associated with damage to the olfactory bulbs beneath the frontal lobes. Patients may note reduced or altered sense of smell. One recent study (Varney 1993) showed that 92% of brain injured patient suffering anosmia (loss of smell) had ongoing problems with employment, even though their neuropsychological testing was relatively normal.

The effects of brain injury on the patient may be equaled or even surpassed by the effect on the patient's family. Brain injuries are known for causing extreme stressors in family and interpersonal relationships.

In general, symptoms of traumatic brain injury should lessen over time as the brain heals but sometimes the symptoms worsen because of the patient's inability to adapt to the brain injury. For this and other reasons it is not uncommon for psychological problems to arise and worsen after brain injury.


A wide variety of symptoms can occur after "brain injury." The nature of the symptoms depends, in large part, on where the brain has been injured. Below find a list of possible physical and cognitive symptoms which can arise from damage to specific areas of the brain:

Frontal Lobe: Forehead

Loss of simple movement of various body parts (Paralysis).
Inability to plan a sequence of complex movements needed to complete multi-stepped tasks, such as making coffee (Sequencing).
Loss of spontaneity in interacting with others.
Loss of flexibility in thinking.
Persistence of a single thought (Perseveration).
Inability to focus on task (Attending).
Mood changes (Emotionally Labile).
Changes in social behavior.
Changes in personality.
Difficulty with problem solving.
Inability to express language (Broca's Aphasia).

Parietal Lobe: near the back and top of the head

Inability to attend to more than one object at a time.
Inability to name an object (Anomia).
Inability to locate the words for writing (Agraphia).
Problems with reading (Alexia).
Difficulty with drawing objects.
Difficulty in distinguishing left from right.
Difficulty with doing mathematics (Dyscalculia).
Lack of awareness of certain body parts and/or surrounding space (Apraxia) that leads to difficulties in self-care.
Inability to focus visual attention.
Difficulties with eye and hand coordination.

Occipital Lobes: most posterior, at the back of the head

Defects in vision (Visual Field Cuts).
Difficulty with locating objects in environment.
Difficulty with identifying colors (Color Agnosia).
Production of hallucinations.
Visual illusions - inaccurately seeing objects.
Word blindness - inability to recognize words.
Difficulty in recognizing drawn objects.
Inability to recognize the movement of object (Movement Agnosia).
Difficulties with reading and writing.

Temporal Lobes: sides of head above ears

Difficulty in recognizing faces (Prosopagnosia).
Difficulty in understanding spoken words (Wernicke's Aphasia).
Disturbance with selective attention to what we see and hear.
Difficulty with identification of, and verbalization about objects.
Short term memory loss.
Interference with long term memory.
Increased and decreased interest in sexual behavior.
Inability to catagorize objects (Categorization).
Right lobe damage can cause persistent talking.
Increased aggressive behavior.

Brain Stem: deep within the brain

Decreased vital capacity in breathing, important for speech.
Difficulty swallowing food and water (Dysphagia).
Difficulty with organization/perception of the environment.
Problems with balance and movement.
Dizziness and nausea (Vertigo).
Sleeping difficulties (Insomnia, sleep apnea).

Cerebellum: base of the skull

Loss of ability to coordinate fine movements.
Loss of ability to walk.
Inability to reach out and grab objects.
Dizziness (Vertigo).
Slurred Speech (Scanning Speech).
Inability to make rapid movements.

Little Known Symptoms / Injuries from Traumatic Brain Injury

Along with the standard injuries involving cognitive ability, personality change, executive function decline, and others which have been widely reported on, there are additional injuries and symptoms suffered by those who have had traumatic brain injury, which are not widely known but can cause profound problems. These include:


Vision disturbances following traumatic brain injury are common, seen in 30% to 85% of cases. These symptoms are often one of the last to be treated and often escape detection. Standard treatment by an eye doctor or ophthalmologist can often fail to find the cause of blurred vision, photo sensitivity, change in field of vision and anomalies of accommodation commonly found after TBI. The most common, difficulties of "accommodation," may result in blurred vision. This is the eyes inability to accurately change focus from far to near or from near to far. Difficulties of "version" are seen in such abnormalities as saccads, pursuit and fixation, and other changes which result in lost of place while reading, skipping lines, or re-reading lines due to abnormal movements of the eye. Thirdly, there are abnormalities of "vergence" which result in occasional or constant eye strain or sense that the print on a book is "shimmering" or "floating" on the page. There can also be abnormalities of the field of vision that can result in lack of awareness of the field of vision on one side or the other side of the body. Finally, there can be abnormalities in light sensitivity which can cause pain and headache in patients.


Sudden sensorineural hearing loss (SNHL) is a common phenomena which can be caused by trauma, infectious disease, or tumor. It is often found in conjunction with damage to the vestibular system of the body, which deals with balance. A common test done by physicians called Romberg Test provides information on the integrity of the system. Audiologist can do hearing tests which can confirm or point to this diagnosis. Many patients recover full or partial hearing after a year or two.


Cranial nerve damage is a common finding in mild to moderate head injury. One of the results can be a loss or alteration in the sense of smell and because of that the sense of taste. The loss of smell is called anosmia. Many neurologists and other physicians now have the ability to test for loss of smell. This loss can occur on each or both nostrils, so do not forget to have each nostril tested separately. In a recent study by Varney and others a PET scan was able to detect the specific brain damage associated with anosmia. If there is an alteration in the way food tastes, or commonly, an inability to cook properly because of lack of smell, please have this testing done.


Especially in cases of moderate and severe brain injury, patients should be routinely given blood tests to see if the human hormonal glands are functioning normally. The pituitary gland is particularly at risk, and blood work should be done to show whether or not the gland is functioning properly. Long term ill effects of low pituitary output may affect the heart, the psychiatric status of the patient, and may have other effects not fully know at this time. Many physicians feel that there needs to be observable damage to the small but powerful glands in the brain in order to consider testing for output. There does not have to be observable damage for such an injury to occur, if there otherwise was a moderate to severe brain injury involved in the patient. These glandular disruptions would be the cause of the very common sexual dysfunction seen in TBI survivors.

Another result of glandular dysfunction following TBI is the onset of cranial diabetes insipidus. Therefore, it is important to be on the lookout for signs of diabetes (unusual thirst, change in urination, lightheadedness or fainting) following TBI.