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Neurocircuit refers to the extensive network of pathways created by neurons in the brain.

Neurodevelopmental Evaluation

See Neuropsychological Evaluation.


Neurofibromatosis is a genetic disorder caused by a mutation in the NF1 or NF2 gene. Neurofibromatosis 1 (NF1) is characterized by multiple benign tumors and patches of skin pigmentation called cafe au lait spots. Neurofibromatosis 2 (NF2) is characterized by tumors of the hearing and balance nerve.


Neurological refers to the nerves and nervous system, including the brain.


A neurologist is a physician who specializes in disorders of the nervous system. A neurologist who treats people with epilepsy is trained to recognize abnormal patterns of brain activity in EEGs and brain abnormalities. A pediatric neurologist is a neurologist who specializes in treating children affected by disorders of the nervous system. An epileptologist is a neurologist who specializes in the treatment of epilepsy.


brain sectionsclick to enlarge photograph

A neuron is a specialized cell that transmits electrical and chemical signals in the body's nervous system. Also known as a nerve cell. The term neuronal refers to the neuron. The term neural refers to the nerves and the nervous system.

Neuropsychological Evaluation

A neuropsychological evaluation involves a battery of tests used to assess cognitive and behavioral functions and identify areas of cognitive impairment. Also known as neurodevelopmental evaluation.


A neuropsychologist is a licensed psychologist with specialized training in brain-behavior relationships and the evaluation of cognitive functions. Neuropsychologists use a battery of standardized tests to assess specific cognitive and behavioral functions and identify areas of cognitive strengths and impairment as they relate to brain functioning.


A neuroradiologist is a physician who interprets images, including x-rays, ultrasounds, CT scans, and MRIs, of the central nervous system, including the brain. A neuroradiologist is trained to recognize abnormalities in brain structure.


A neurosurgeon is a surgeon who specializes in performing surgery on the nervous system, including the brain. A neurosurgeon who treats people with epilepsy is trained in the identification and resection (surgical removal) of brain regions where seizures originate. Neurosurgeons are often also qualified to treat epilepsy with implants such as the vagus nerve stimulator (VNS).


Neurotransmitters are specialized chemicals released at the synapse that act as messengers between nerve cells.

Occipital Lobe

brain sectionsclick to enlarge photograph

The occipital lobe is located at the back of the cerebrum, behind the temporal and parietal lobes. One of the most important functions of this lobe is the processing of visual stimuli.

Parietal Lobe

brain sectionsclick to enlarge photograph

The parietal lobe is located at the top of the cerebrum, behind the frontal lobe. This lobe receives much of the body's sensory stimuli and is responsible for integrating and interpreting information related to touch, sound, smell, and vision. The area of the parietal lobe most involved in sensation is the sensory strip, portions of which have been linked to specific body parts and/or functions.


Paroxysmal refers to the sudden occurrence of a symptom, like an attack or a seizure.

Partial Seizures

Partial seizures are seizures that begin in one area, or focus, of the brain. They may or may not affect consciousness, depending on where in the brain they occur and the specialized brain structures they might involve. A partial seizure that does not affect consciousness is called a simple partial seizure. A partial seizure that alters consciousness is called a complex partial seizure.

Partial Seizure with Secondary Generalization

A partial seizure with secondary generalization is a seizure that begins focally, meaning in one area, and progresses very rapidly to involve the entire brain. Sometimes referred to as secondary generalized seizure.

Petit Mal Seizure

See Absence Seizure.


Pharmacological refers to pharmacology, which is the study of drugs and their properties, interactions, and reactions on living organisms.


Plasticity is the brain's astounding capacity to create new connections and relearn information or behaviors that were lost due to seizures or other insults to the brain. The developing brain does this by creating new functional neuronal networks. The brain has the greatest plasticity in childhood, and the potential for plasticity diminishes over time.

Polypharmacy or Polytherapy

Polypharmacy or polytherapy is the use of more than one anticonvulsant medication simultaneously for the treatment of epilepsy. Polytherapy may also be the use of an anticonvulsant medication in combination with a dietary therapy or the vagus nerve stimulator. Also known as combination therapy.

Positron Emission Tomography (PET)

Positron emission tomography (PET) is a neuroimaging technique in which a small amount of short-lived radioactive tracer is injected into the body and a scanner is used to determine where in the body the tracer is being metabolized. PET can be used to look at metabolic activity in the brain and determine the source of seizure activity (often an area of reduced metabolism in comparison to surrounding tissue) in preparation for seizure surgery.


Postictal refers to the period of time after a seizure during which an individual may be recovering from the effects of the seizure, including feelings of drowsiness and disorientation. Postictal also refers to the changes on an EEG following a seizure.


Pruning is the process by which unused or unnecessary portions of the brain's complex network of neural connections are periodically eliminated. This natural process improves the efficiency of brain's neurocircuitry.


A pseudoseizure is a nonepileptic event resembling a seizure, which results from subconscious mental activity. May also be referred to as a nonepileptic event.


A psychiatrist is a medical doctor who specializes in the diagnosis and treatment of mental and behavioral disorders. A psychiatrist who treats people with epilepsy is familiar with the cognitive and behavioral issues that are common to the disorder and knows what treatment options are most effective for these issues, including medication options.


A psychologist is a licensed professional who specializes in the diagnosis and treatment of mental, emotional, and behavioral problems, and may be involved in evaluation, testing, counseling, and/or psychotherapy.

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This content was last reviewed on November 20, 2006.