Frontal lobe epilepsy - AbsoluteAstronomy.com

Frontal lobe epilepsy, or FLE, is a neurological disorder that is characterized by brief, recurring seizures that arise in the frontal lobes of the brain, often while the patient is sleeping. It is the second most common type of epilepsy

Epilepsy

Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...

after temporal lobe epilepsy

Temporal lobe epilepsy

Temporal lobe epilepsy a.k.a. Psychomotor epilepsy, is a form of focal epilepsy, a chronic neurological condition characterized by recurrent seizures. Over 40 types of epilepsies are known. They fall into two main categories: partial-onset epilepsies and generalized-onset epilepsies...

(TLE), and is related to the temporal form by the fact that both forms are characterized by the occurrence of partial (focal) seizures. Partial seizures occurring in the frontal lobes can occur in one of two different forms: either simple partial seizure

Simple partial seizure

Simple partial seizures are seizures which affect only a small region of the brain, often the temporal lobes and/or hippocampi. People who have simple partial seizures retain consciousness...

s (that do not affect awareness or memory) or complex partial seizure

Complex partial seizure

A complex partial seizure is an epileptic seizure that is associated with bilateral cerebral hemisphere involvement and causes impairment of awareness or responsiveness, i.e. loss of consciousness.-Presentation:...

s (that affect awareness or memory either before, during or after a seizure). The symptoms and clinical manifestations of frontal lobe epilepsy can differ depending on which specific area of the frontal lobe is affected.

The onset of a seizure may be hard to detect since the frontal lobes contain and regulate many structures and functions about which relatively little is known. Due to the lack of knowledge surrounding the functions associated with the frontal lobes, seizures occurring in these regions of the brain may produce unusual symptoms which can often be misdiagnosed as a psychiatric disorder, non-epileptic seizure or a sleep disorder.

During the onset of a seizure, the patient may exhibit abnormal body posturing, sensorimotor tic

Tic

A tic is a sudden, repetitive, nonrhythmic, stereotyped motor movement or vocalization involving discrete muscle groups. Tics can be invisible to the observer, such as abdominal tensing or toe crunching. Common motor and phonic tics are, respectively, eye blinking and throat clearing...

s, or other abnormalities in motor skills. In rare cases, uncontrollable laughing or crying may occur during a seizure. Afflicted persons may or may not be aware that they are behaving in an abnormal manner, depending on the patient and type of seizure. A brief period of confusion known as a postictal state

Postictal state

The postictal state is the altered state of consciousness that a person enters after experiencing a seizure. It usually lasts between 5 and 30 minutes, but sometimes longer in the case of larger or more severe seizures and is characterized by drowsiness, confusion, nausea, hypertension, headache or...

may sometimes follow a seizure occurring in the frontal lobes. However, these postictal states are oftentimes undetectable and generally do not last as long as the periods of confusion following seizures that occur in the temporal lobes.

There are a variety of different causes of frontal lobe epilepsy ranging from genetics to head trauma that result in lesions in the frontal lobes. Although frontal lobe epilepsy is often misdiagnosed, tests such as prolonged EEG

Electroencephalography

Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...

monitoring and/or a MRI

Magnetic resonance imaging

Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...

scan of the frontal lobes can be administered in order to reveal the presence of a tumor or vascular malformation. Unlike most epileptic EEGs

Electroencephalography

Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...

, the abnormalities in FLE EEGs

Electroencephalography

Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...

precede the physical onset of the seizure and aid in localization of the seizure's origin. Medications such as anticonvulsants can typically control the onset of seizures, however, if medications are ineffective the patient may undergo surgery

Surgery

Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...

to have focal areas of the frontal lobe removed.

Anatomy of Frontal Lobe Cortex

Due to the difference in brain processing and function as well as various surface anatomy landmarks, the frontal lobes have traditionally been divided into two major areas known as the precentral cortex and prefrontal cortex

Prefrontal cortex

The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...

Precentral Cortex

The precentral cortex is an area of the frontal cortex that is located directly anterior to the central sulcus

Central sulcus

-External links:* via the Neuroscience Information Framework...

and includes both the primary motor cortex

Primary motor cortex

The primary motor cortex is a brain region that in humans is located in the posterior portion of the frontal lobe. Itworks in association with pre-motor areas to plan and execute movements. M1 contains large neurons known as Betz cells, which send long axons down the spinal cord to synapse onto...

and the supplementary motor area

Supplementary motor area

The supplementary motor area is a part of the sensorimotor cerebral cortex . It was included, on purely cytoarchitectonic arguments, in area 6 of Brodmann and the Vogts...

. Inputs that project to both of these areas arise from a variety of locations in the brain that integrate sensory stimuli including the primary motor cortex

Primary motor cortex

, the thalamus

Thalamus

The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...

and corticospinal projections. These two areas along with several other main functional areas control both the preparation of motor movement as well as the execution of movements. These main functional areas are crucial to the development of the motor related symptoms associated with frontal lobe epilepsy focally when seizures are located within these defined areas. The major functional areas include:

Primary Motor Cortex
- Contains large neurons that project axons down to the spinal cord where they synapse onto alpha motor neurons. These neurons are involved in the planning of motor movements and the refining of motor movements based on sensory inputs that are received from the cerebellum
  Cerebellum
  The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...
  
  .

Supplementary motor area
Supplementary motor area
The supplementary motor area is a part of the sensorimotor cerebral cortex . It was included, on purely cytoarchitectonic arguments, in area 6 of Brodmann and the Vogts...
- Area anterior to the primary motor cortex that is involved in planning complex motor movements and coordinating movements along both hands. The main inputs for this area are received from the thalamus
  Thalamus
  The thalamus is a midline paired symmetrical structure within the brains of vertebrates, including humans. It is situated between the cerebral cortex and midbrain, both in terms of location and neurological connections...
  
  .

Frontal eye field
- The frontal eye field is a posterior part of the middle frontal gyrus
  Middle frontal gyrus
  The middle frontal gyrus makes up about one-third of the frontal lobe of the human brain....
  
  and is involved in the control of saccadic
  Saccade
  A saccade is a fast movement of an eye, head or other part of an animal's body or device. It can also be a fast shift in frequency of an emitted signal or other quick change. Saccades are quick, simultaneous movements of both eyes in the same direction...
  
  , contralateral and conjugate eye movement. This area receives its main inputs from both the occipital cortex
  Occipital lobe
  The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area 17, commonly called V1...
  
  and dorsal thalamus.

Broca's Area
Broca's area
Broca's area is a region of the hominid brain with functions linked to speech production.The production of language has been linked to the Broca’s area since Pierre Paul Broca reported impairments in two patients. They had lost the ability to speak after injury to the posterior inferior frontal...
- Controls the motor movements of both the tongue and larynx that enables speech formation. This area receives direct inputs from the primary motor area as well as Wernicke's area located in the temporal lobe.

Prefrontal Cortex

The prefrontal cortex, the most anterior region of the brain, comprises several key areas that are particularly important for higher mental functions that control various aspects of human personality including anticipation and planning, initiative/judgement, memory and the control of decision making. Damage or lesions to this region of the brain can result in major changes in personality.
A classic example is Phineas Gage

Phineas Gage

Phineas P. Gage was an American railroad construction foreman now remembered for his improbablesurvival of an accident in which a large iron rod was driven completely through his head, destroying much of his brain's left frontal lobe, and for that injury's reported effects on his personality and...

, who exhibited a change in behavior after one or both frontal lobes were destroyed by a large iron bar accidentally driven through his head (though Gage did not exhibit the aggression, antiosocial behavior, or loss of impulse control sometimes reported in patients with similar injuries).

There are two main regions of the prefrontal cortex that each control various aspects of behavior and personality:

Dorsolateral Prefrontal Cortex
Dorsolateral prefrontal cortex
The dorsolateral prefrontal cortex , according to a more restricted definition, is roughly equivalent to Brodmann areas 9 and 46. According to a broader definition DL-PFC consists of the lateral portions of Brodmann areas 9 – 12, of areas 45, 46, and the superior part of area 47. These regions...
- This area is associated with the impairment of the cognitive abilities that control and regulate behavior and long term memory formation (especially relating to procedural sequence memory) when either brain damage or a lesion is present.

Orbitofrontal Cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...
- The orbitofrontal cortex has similar functions as the dorsolateral prefrontal cortex but is thought to be mainly responsible for the ability to make choices and determine right from wrong.

Symptoms

Epileptic symptoms are frequently the product of the spread of overactivation occurring within one central foci that travels to lateral brain regions thereby causing an array of symptoms. Due to the massive amount of diversity in both the cognitive and motor functions that occur within the frontal lobes, there is an immense variety in the types of symptoms that can arise from epileptic seizures based on the side and topography of the focal origin. In general these symptoms can range anywhere from asymmetric and abnormal body positionsing to repetitive vocal outburts and repetitive jerking movements. The symptoms typically come in short bursts that last less than a minute and often occur while a patient is sleeping. In most cases, a patient will experience a physical or emotional Aura

Aura (symptom)

An aura is a perceptual disturbance experienced by some migraine sufferers before a migraine headache, and the telltale sensation experienced by some people with epilepsy before a seizure. It often manifests as the perception of a strange light, an unpleasant smell or confusing thoughts or...

of tingling, numbness or tension prior to a seizure occurring. Fear is associated with temporal and frontal lobe epilepsies, but in FLE the fear is predominantly expressed on the person's face whereas in TLE the fear is subjective and internal, not perceptible to the observer.

Tonic posture and clonic movements are common symptoms among most of the areas of the frontal lobe, therefore the type of seizures associated with frontal lobe epilepsy are commonly called tonic-clonic seizures. Dystonic motor movements are common to both TLE

Temporal lobe epilepsy

and FLE, but are usually the first symptom in FLE episodes where they are quite brief and do not affect consciousness. The seizures are complex partial

Complex partial seizure

, simple partial

Simple partial seizure

Simple partial seizures are seizures which affect only a small region of the brain, often the temporal lobes and/or hippocampi. People who have simple partial seizures retain consciousness...

, secondarily generalized or a combination of the three. These partial seizures are often misdiagnosed as psychogenic seizures

Psychogenic non-epileptic seizures

Psychogenic non-epileptic seizures , also known as Non-Epileptic Attack Disorders, are events superficially resembling an epileptic seizure, but without the characteristic electrical discharges associated with epilepsy. Instead, PNES are psychological in origin, and may be thought of as similar to...

. A wide range of more specific symptoms arise when different parts of the frontal cortex are affected.

Supplementary motor area
Supplementary motor area
The supplementary motor area is a part of the sensorimotor cerebral cortex . It was included, on purely cytoarchitectonic arguments, in area 6 of Brodmann and the Vogts...

(SMA)
- The onset and relief of the seizure are quite abrupt.
- The tonic posturing in this area is unilateral or asymmetric between the left and right hemispheres. A somatosensory aura frequently precedes many large motor and vocal symptoms and most often the afflicted person is responsive.
- Motor symptoms: Facial grimacing and complex automatisms like kicking and pelvic thrusting
- Vocal symptoms: Laughing, yelling, or speech arrest.

Primary motor cortex
Primary motor cortex
The primary motor cortex is a brain region that in humans is located in the posterior portion of the frontal lobe. Itworks in association with pre-motor areas to plan and execute movements. M1 contains large neurons known as Betz cells, which send long axons down the spinal cord to synapse onto...
- The primary motor cortex has jacksonian seizure
  Jacksonian seizure
  Jacksonian seizure is associated with a form of epilepsy. They involve a progression of the location of the seizure in the brain, which leads to a "march" of the motor presentation of symptoms.-Presentation:...
  
  s that spread to adjacent areas of the lobe which often trigger a second round of seizures originating in another cortical area. The seizures are much simpler than those that originate in the SMA and are usually clonic or myoclonic movements with speech arrest. Some dystonic or contralateral adversive posturing may also be present.

Medial frontal, cingulate gyrus, orbitofrontal
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

, or frontopolar regions
- Motor symptoms of seizures in this area are accompanied by emotional feelings and viscerosensory symptoms. Motor and vocal agitation are similar to that of the SMA with short repetitive thrashing, pedaling, thrusting, laughing, screaming and/or crying.
- This is some of what can cause the misdiagnosis of a psychological disorder.

Dorsolateral cortex
Dorsolateral prefrontal cortex
The dorsolateral prefrontal cortex , according to a more restricted definition, is roughly equivalent to Brodmann areas 9 and 46. According to a broader definition DL-PFC consists of the lateral portions of Brodmann areas 9 – 12, of areas 45, 46, and the superior part of area 47. These regions...
- This area does not seem to have many motor symptoms beyond tonic posturing or clonic movements. Contralateral or less commonly ipsilateral head turn and eye deviation are commonly associated with this area as well.

Operculum
Operculum (brain)
Operculum, derived from Latin, meaning "little lid", refers to the cerebral cortex on the outside surface of the brain bordering the lateral sulcus, and the roof and floor of the lateral sulcus. Neuroscience divides the operculum into orbital, frontal, parietal and temporal regions, after the...
- Many of the symptoms associated with this area involve the head and digestive tract: swallowing, salivation, mastication and possibly gustatory hallucinations. Preceding the seizure the person is fearful and often has an epigastric aura. There is not much physical movement except clonic facial movements. Speech is often arrested.

Common Misdiagnoses

Episodes that include complex hyperactivity of the proximal portions of the limbs that lead to increased overall motor activity are called hypermotor seizures. When associated with bizarre movements and vocalizations these seizures are often misdiagnosed as pseudoseizures or other episodic movement disorders such as psychogenic movement disorders, familial paroxysmal dystonic choreoathetosis

Paroxysmal Nonkinesigenic Dyskinesia

Paroxysmal Nonkinesigenic Dyskinesia is an episodic movement disorder first described by Mount and Reback in 1940 under the name "Familial paroxysmal choreoathetosis"...

, paroxysmal kinesogenic choreoathetosis

Paroxysmal kinesogenic choreoathetosis

Wikipedia ArticleParoxysmal kinesigenic choreathetosis, ' also called Paroxysmal Kinesigenic Dyskinesia ' is a hyperkinetic movement disorder characterized by attacks of involuntary movements, which are triggered by sudden voluntary movements...

, or episodic ataxia type 1

Episodic ataxia

Episodic ataxia is an autosomal dominant disorder characterized by sporadic bouts of ataxia with or without myokymia . There are seven types recognised but the majority are due to two recognized entities. Ataxia can be provoked by stress, startle, or heavy exertion such as exercise. Symptoms can...

. Hypermotor seizure in children are often confused with pavor nocturnus

Night terror

A night terror, also known as a sleep terror, incubus attack, or pavor nocturnus, is a parasomnia disorder that predominantly affects children, causing feelings of terror or dread, typically occur in the first few hours of sleep during stage 3 or 4 NREM sleep...

(night terrors). Paroxysmal nocturnal dystonia or hypnogenic paroxysmal dystonia are other names given to describe FLE symptoms but are simply just FLE.

Autosomal Dominant Nocturnal Frontal Lobe Epilepsy

Autosomal dominant nocturnal frontal lobe epilepsy

Autosomal dominant nocturnal frontal lobe epilepsy is a rare epileptic disorder that causes frequent violent seizures during sleep. These seizures often involve complex motor movements, such as hand clenching, arm raising/lowering, and knee bending. Vocalizations such as shouting, moaning, or...

(ADNFLE) is the best understood form of frontal lobe epilepsy but is often misdiagnosed as sleep apnea

Sleep apnea

Sleep apnea is a sleep disorder characterized by abnormal pauses in breathing or instances of abnormally low breathing, during sleep. Each pause in breathing, called an apnea, can last from a few seconds to minutes, and may occur 5 to 30 times or more an hour. Similarly, each abnormally low...

. Both disorders are characterized by awakening during the night which leads to daytime sleepiness. Some symptoms of sleep apnea

Sleep apnea

overlap with those of ADNFLE

Autosomal dominant nocturnal frontal lobe epilepsy

, such as sudden awakening accompanied by a feeling of choking and on occasion motor activity which makes diagnosis difficult based on symptoms alone. Video surveillance as well as EEG

Electroencephalography

Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...

is occasionally needed to differentiate between the two disorders. It has been reported that sleep apnea

Sleep apnea

might be associated with epilepsy which would account for some of the misdiagnoses.

Causes

The origins of frontal lobe seizures range from tumors to head trauma to genetics. Tumors account for about one third of all frontal lobe epilepsy cases. Low-grade tumors such as ganglioglioma

Ganglioglioma

Ganglioglioma is a tumour that arises from ganglion cells in the central nervous system.The term "gangliocytoma" is sometimes equated with ganglioglioma. However, it is also sometimes equated with ganglioneuroma. In this context, the glial nature of the tumor is de-emphasized...

s, low-grade glioma

Glioma

A glioma is a type of tumor that starts in the brain or spine. It is called a glioma because it arises from glial cells. The most common site of gliomas is the brain.-By type of cell:...

s, and epidermoid

Epidermoid cyst

An epidermoid cyst is a benign cyst usually found on the skin. The cyst develops out of ectodermal tissue. Histologically, it is made of a thin layer of squamous epithelium.-Terminology:...

tumors are most common, but many high-grade tumors were most likely once involved with seizures. Other lesions on the frontal lobe such as hamartoma

Hamartoma

A hamartoma is a benign, focal malformation that resembles a neoplasm in the tissue of its origin. This is not a malignant tumor, and it grows at the same rate as the surrounding tissues. It is composed of tissue elements normally found at that site, but which are growing in a disorganized mass...

s and nodular heterotopias can cause frontal lobe symptoms as well. Birth defects such as vascular malformation are known to cause seizures, especially arteriovenous malformations

Cerebral arteriovenous malformation

A cerebral arteriovenous malformation is an abnormal connection between the arteries and veins in the brain.-Signs and symptoms:The most frequently observed problems related to an AVM are headaches and seizures while at least 15% of the population at detection have no symptoms at all...

and cavernous angioma

Cavernous angioma

Cavernous angioma, also known as cerebral cavernous malformation , cavernous haemangioma, and cavernoma, is a vascular disorder that alternately has been classified as neoplastic or hamartomatous. It is characterized by grossly dilated blood vessels with a single layer of endothelium and an...

s. Head trauma frequently causes damage to the frontal lobe and can cause seizures directly or indirectly through gliosis

Gliosis

Gliosis is a proliferation of astrocytes in damaged areas of the central nervous system . This proliferation usually leads to the formation of a glial scar....

. Seizures originating directly from head trauma usually occur within a few months, but occasionally they can take years to manifest. On occasion encephalitis

Encephalitis

Encephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...

can cause frontal lobe seizures but it is most often associated with temporal lobe affliction. The main genetic cause of frontal lobe epilepsy is an autosomal dominant disease called Autosomal Dominant Nocturnal Frontal Lobe Epilepsy

Autosomal dominant nocturnal frontal lobe epilepsy

, which involves mutations in 2 nicotinic acetylcholine receptor

Nicotinic acetylcholine receptor

Nicotinic acetylcholine receptors, or nAChRs, are cholinergic receptors that form ligand-gated ion channels in the plasma membranes of certain neurons and on the postsynaptic side of the neuromuscular junction...

genes. A genetic mutation on chromosome 22 has also been associated with another genetic form of the disorder.

Frequency

Epilepsy

is a relatively common disorder, affecting between 0.5-1% of the population, and frontal lobe epilepsy accounts for about 1-2% of all epilepsies. The most common subdivision of epilepsy is symptomatic partial epilepsy, which causes simple partial seizure

Simple partial seizure

Simple partial seizures are seizures which affect only a small region of the brain, often the temporal lobes and/or hippocampi. People who have simple partial seizures retain consciousness...

s, and can be further divided into temporal and frontal lobe epilepsy. Although the exact number of cases of frontal lobe epilepsy is not currently known, it is known that FLE is the less common type of partial epilepsy, accounting for 20-30% of operative procedures involving intractable epilepsy. The disorder also has no gender or age bias, affecting males and females of all ages. In a recent study, the mean subject age with frontal lobe epilepsy was 28.5 years old, and the average age of epilepsy onset for left frontal epilepsy was 9.3 years old whereas for right frontal epilepsy it was 11.1 years old.

Social Impacts and Quality of Life

Epilepsy has a substantial impact on the quality of life of the individuals that are afflicted with it. Physicians and researchers are coming to understand that the impact on the quality of life of the patient is as important as the effects of the seizures. Quality of life questionnaires and other assessment tools have been created to help quantify quality of life for individual patients. They consider such factors as physical health (including numbers and severity of seizures, medication side effects etc.), mental health, social relationships, lifestyle, role activities and life fulfillment. A Center for Disease Control study reported that seizure sufferers were more likely to have lower education levels, higher unemployment, higher levels of pain, hypersomnia

Hypersomnia

Hypersomnia is a disorder characterized by excessive amounts of sleepiness.There are two main categories of hypersomnia: primary hypersomnia and recurrent hypersomnia...

/insomnia

Insomnia

Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...

, increased psychological distress and social isolation/connection issues. Some of the issues which impact quality of life for epileptics are: ability to drive and travel, the ability to date, marry and have children, the ability to have a job and independence, the ability to have an education and learn, and the ability to have good health and mental functioning. Future research is needed to find ways to not only control frontal lobe seizures, but to also address the specific quality of life issues that plague those with frontal lobe epilepsy.

Driving and Transportation Restrictions
- Driving and travel restrictions are one of the greatest limitations that epileptic patients experience. Laws restricting driving privileges vary greatly in the United States as well as across the world. In the United States, 28 states require a patient to be seizure free for fixed periods of time ranging from 3–12 months. However, research done by Johns Hopkins University
  Johns Hopkins University
  The Johns Hopkins University, commonly referred to as Johns Hopkins, JHU, or simply Hopkins, is a private research university based in Baltimore, Maryland, United States...
  
  showed that there was no difference in seizure related fatal crash rates in states with 3 month restrictions versus states with 6-12 month seizure free restrictions. In 23 states, the restrictions and seizure free periods vary depending on the type of epilepsy and the individual case and in 13 states physicians were responsible for determining whether their patients should be allowed to drive. In 6 of those 13 states physicians could be held legally liable for their decisions regarding their epileptic patients’ driving capabilities. In many states, patients can also be legally liable for accidents, injury, damage and death caused by seizure related accidents.
- One of the major arguments in favor of restricting the licensing of epileptic drivers is the concern for public safety. However, the Johns Hopkins study showed that in a particular 2 year timeframe only .2% of fatal crashes occurred as a result of seizures. Alcohol related crash fatalities caused 156 times more driver deaths than seizure related crashes and young drivers between the ages of 16 and 24 were 123 times more likely to die in a fatal crash caused by their inexperience than an epileptic driver was to die in a crash that resulted from a seizure.
- Frontal lobe epileptic seizures unlike other epileptic seizures create symptoms that are as dangerous as loss of consciousness and much more difficult to discern from other problems such as drug and alcohol abuse, psychiatric disorders and disobedience. Jerking movements/lack of motor control, pedaling, pelvic thrusting, lapses in cognitive functioning and other hallmark symptoms of frontal lobe epileptic seizures all create dangerous behavior behind the wheel. Studies have not been done to date to determine the differential risk posed by drivers with frontal lobe epilepsy relative to the general epileptic population.

Hormones & Pregnancy Issues
- Hormonal changes and pregnancy can shift seizure activity and the use of antiepileptic drugs can alter the efficacy of hormones as well as cause congenital malformations in fetuses. Seizure control in pregnant women is very important to the welfare of both the developing fetus and the mother. Hormonal shifts at puberty
  Puberty
  Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...
  
  , with birth control and at menopause can also cause changes in the frequency and severity of seizures and must be closely monitored. Increased seizure activity is reported by 50% of women during the course of the pregnancy due to changing levels of hormones, fluids, salts and absorption and elimination of medications.

Employment
- A report by the Epilepsy Foundation noted that the unemployment
  Unemployment
  Unemployment , as defined by the International Labour Organization, occurs when people are without jobs and they have actively sought work within the past four weeks...
  
  rate amongst epileptics is 25% and in patients whose seizures are poorly controlled the rate jumps to 50%. Even though epileptics are protected under The Americans with Disabilities Act, employment discrimination and high rates of unemployment due to employer attitudes still exist. A study in the UK showed that 16% of employers surveyed felt there were no jobs in their company suitable for epileptics and that 21% felt that employing an epileptic would be a “major issue”. Fifty percent of the employers said they had a high concern regarding employing epileptics with most citing safety concerns/workplace accidents as their major issue. Patients with frontal lobe epilepsy may be particularly prone to being discriminated against in employment and subject to higher rates of termination due to the unusual motor symptoms, speech, vocal outbursts and cognitive/judgment symptoms displayed during frontal lobe seizures. Frontal lobe seizures also tend to come on suddenly and progress rapidly making it difficult for an employer to control the exposure of the seizure to others.

Education/Learning & Cognitive Function
- Patients with frontal lobe epilepsy will likely also experience issues with learning and education. Many factors contribute to these issues including the impact of anticonvulsant medications. Anticonvulsant medications cause patients to feel “foggy” and sluggish. Drugs such as Topiramate
  Topiramate
  Topiramate is an anticonvulsant drug. It was originally produced by Ortho-McNeil Neurologics and Noramco, Inc., both divisions of the Johnson & Johnson Corporation. This medication was discovered in 1979 by Bruce E. Maryanoff and Joseph F. Gardocki during their research work at McNeil...
  
  cause problems such as mental blunting, word retrieval difficulties and irritability. Phenobarbital, Primidone and Vigabatrin can cause depression
  Depression (mood)
  Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behaviour, feelings and physical well-being. Depressed people may feel sad, anxious, empty, hopeless, helpless, worthless, guilty, irritable, or restless...
  
  and suicidal tendencies. Stress and lack of sleep during exam periods can trigger seizures and many school sports teams restrict or ban epileptics from sports for safety and liability reasons. Frontal lobe epilepsy sufferers also exhibit dysfunctional cognitive skills and memory issues which can make learning challenging. Research has shown that frontal lobe epilepsy has a greater negative impact than other forms of epilepsy on cognitive functioning. Frontal lobe epileptics show decreased cognitive capabilities in the following areas: humor appreciation, recognition of emotional expressions, response selection/initiation and inhibition, hyperactivity, conscientiousness, obsession, addictive behavior
  Addictive behavior
  Addictive behavior is any activity, substance, object, or behavior that becomes the major focus of a person's life, during which they withdraw from other activities. Along with this, there are often other signs of having an addiction either physically, mentally, or socially.A person can become...
  
  , motor coordination
  Motor coordination
  thumb|right|Motor coordination is shown in this animated sequence by [[Eadweard Muybridge]] of himself throwing a diskMotor coordination is the combination of body movements created with the kinematic and kinetic parameters that result in intended actions. Such movements usually smoothly and...
  
  and planning, attention span, performance speed, continuous performance without intrusion and interference errors, copying and recall, concept formation, anticipatory behavior, memory span
  Memory span
  In psychology and neuroscience, memory span is the longest list of items that a person can repeat back in correct order immediately after presentation on 50% of all trials. Items may include words, numbers, or letters. The task is known as digit span when numbers are used. Memory span is a common...
  
  , working memory
  Working memory
  Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...
  
  , executive planning, visuo-spatial organization, mental flexibility, conceptual shift, problem solving, programming of complex motor sequences, impulse control, judgment and forecasting of consequences.

Physical Health & Risk Of Other Conditions
- Patients with epilepsy face a greater risk of accidents, injury and other medical conditions than the general population. A European study showed that epileptics were at greater risk for accidental injuries related to seizures such as concussions, abrasions and wounds and reported more hospitalizations and medical action than the general population. Other studies have shown that epileptics are at a greater risk of seizure related drowning, suffocation, broken bones and burns and more likely to die in a fatal automobile crash.
- Epilepsy Ontario reports that epileptics are also more likely to have other conditions than the general population such as: 30% of autistic
  Autism
  Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
  
  children have epilepsy, 33% of cerebral palsy
  Cerebral palsy
  Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
  
  patients have epilepsy, 15-20% of fragile X syndrome
  Fragile X syndrome
  Fragile X syndrome , Martin–Bell syndrome, or Escalante's syndrome , is a genetic syndrome that is the most commonly known single-gene cause of autism and the most common inherited cause of intellectual disability...
  
  patients have epilepsy, 50% of children with learning disabilities will have some form of epilepsy, 3-10% of patients with Lennox-Gastaut syndrome will have epilepsy, 80% of children with Rett syndrome
  Rett syndrome
  Rett syndrome is a neurodevelopmental disorder of the grey matter of the brain that almost exclusively affects females. The clinical features include small hands and feet and a deceleration of the rate of head growth . Repetitive hand movements, such as wringing and/or repeatedly putting hands into...
  
  will have epilepsy and 80% of patients with Tuberous Sclerosis
  Tuberous sclerosis
  Tuberous sclerosis or tuberous sclerosis complex is a rare multi-system genetic disease that causes non-malignant tumors to grow in the brain and on other vital organs such as the kidneys, heart, eyes, lungs, and skin. A combination of symptoms may include seizures, developmental delay, behavioral...
  
  will have epilepsy.

Mental/Emotional Health
- Epileptic patients are more prone to suffer psychological and social dysfunction than individuals that do not have epilepsy. They report higher levels of anxiety
  Anxiety
  Anxiety is a psychological and physiological state characterized by somatic, emotional, cognitive, and behavioral components. The root meaning of the word anxiety is 'to vex or trouble'; in either presence or absence of psychological stress, anxiety can create feelings of fear, worry, uneasiness,...
  
  and stress due to social isolation, discrimination, the unpredictability of their seizures and people’s reactions to them as well as fear of injury, death and brain damage from their seizures. Anticonvulsants can also result in lower functioning, depression
  Depression (mood)
  Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behaviour, feelings and physical well-being. Depressed people may feel sad, anxious, empty, hopeless, helpless, worthless, guilty, irritable, or restless...
  
  , sluggishness and suicidal thoughts. Approximately 20% of epileptics are depressed and the rate of suicide amongst epileptics is 5 times the rate in the general population.
- Frontal lobe epileptics experience more significant social effects because the manifested symptoms are more unusual. Symptoms such as screaming, bicycling limbs, pelvic thrusting, inhibition control and other outbursts can be particularly embarrassing and isolating for the patient.

Treatments

There are several different ways to treat frontal lobe epileptic seizures, however, the most common form of treatment is through the use of anticonvulsant medications

Anticonvulsant

The anticonvulsants are a diverse group of pharmaceuticals used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder, since many seem to act as mood stabilizers, and in the treatment of neuropathic pain. The goal of an...

that help to prevent seizures from occurring. In some cases, however, when medications are ineffective, a neurologist

Neurologist

A neurologist is a physician who specializes in neurology, and is trained to investigate, or diagnose and treat neurological disorders.Neurology is the medical specialty related to the human nervous system. The nervous system encompasses the brain, spinal cord, and peripheral nerves. A specialist...

may choose to operate on the patient in order to remove the focal area of the brain in which the seizures are occurring. Other treatments that can be administered to aid in reducing the occurrence of seizures include the implementation of a specific, regimented diet and/or the implantation of a vagus nerve stimulator
Vagus nerve stimulation
Vagus nerve stimulation is an adjunctive treatment for certain types of intractable epilepsy and treatment-resistant depression.- Mechanism of action :...

.

Medications

Anticonvulsants are the most successful medication in reducing and preventing seizures from reoccurring. The goal of these medications in being able to reduce the reoccurrence of seizures is to be able to limit the amount of rapid and extensive firing of neurons so that a focal region of neurons cannot become over-activated thereby initiating a seizure. Although anticonvulsants are able to reduce the amount of seizures that occur in the brain, no medication has been discovered to date that is able to prevent the development of epilepsy following a head injury

Head injury

Head injury refers to trauma of the head. This may or may not include injury to the brain. However, the terms traumatic brain injury and head injury are often used interchangeably in medical literature....

. There are a wide range of anticonvulsants that have both different modes of action and different abilities in preventing certain types of seizures. Some of the anticonvulsants that are prescribed to patients today include: Carbamazepine

Carbamazepine

Carbamazepine is an anticonvulsant and mood-stabilizing drug used primarily in the treatment of epilepsy and bipolar disorder, as well as trigeminal neuralgia...

(Tegretol), Phenytoin

Phenytoin

Phenytoin sodium is a commonly used antiepileptic. Phenytoin acts to suppress the abnormal brain activity seen in seizure by reducing electrical conductance among brain cells by stabilizing the inactive state of voltage-gated sodium channels...

(Dilantin Kapseals), Gabapentin

Gabapentin

Gabapentin is a pharmaceutical drug, specifically a GABA analogue. It was originally developed for the treatment of epilepsy, and currently is also used to relieve neuropathic pain...

(Neurontin), Levetiracetam (Keppra), Lamotrigine

Lamotrigine

Lamotrigine, marketed in the US and most of Europe as Lamictal by GlaxoSmithKline, is an anticonvulsant drug used in the treatment of epilepsy and bipolar disorder. It is also used as an adjunct in treating depression, though this is considered off-label usage...

(Lamictal), Topiramate

Topiramate

Topiramate is an anticonvulsant drug. It was originally produced by Ortho-McNeil Neurologics and Noramco, Inc., both divisions of the Johnson & Johnson Corporation. This medication was discovered in 1979 by Bruce E. Maryanoff and Joseph F. Gardocki during their research work at McNeil...

(Topamax), Tiagabine

Tiagabine

Tiagabine -Indications:Tiagabine is approved by U.S. Food and Drug Administration as an adjunctive treatment for partial seizures in ages 12 and up. It may also be prescribed to treat anxiety disorders and neuropathic pain . For anxiety and neuropathic pain, tiagabine is used primarily to augment...

(Gabitril), Zonisamide

Zonisamide

Zonisamide is a sulfonamide anticonvulsant approved for use as an adjunctive therapy in adults with partial-onset seizures for adults; infantile spasm, mixed seizure types of Lennox-Gastaut syndrome, myoclonic, and generalized tonic clonic seizure.-History:...

(Zonegran) and Pregabalin

Pregabalin

Pregabalin is an anticonvulsant drug used for neuropathic pain and as an adjunct therapy for partial seizures with or without secondary generalization in adults. It has also been found effective for generalized anxiety disorder and is approved for this use in the European Union. It was designed...

(Lyrica).

Chemical Pathways for Anticonvulsants

Anticonvulsant medications can affect one or more ion channel pathways depending on the type of seizure. They typically affect GABA, sodium channels, calcium channels, glutamate, or a combination of these. One mechanism involves the increased release of GABA

Gamma-aminobutyric acid

γ-Aminobutyric acid is the chief inhibitory neurotransmitter in the mammalian central nervous system. It plays a role in regulating neuronal excitability throughout the nervous system...

or the inhibition of its metabolism so that it is present in the synapse

Chemical synapse

Chemical synapses are specialized junctions through which neurons signal to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system. They are crucial to the biological computations that underlie...

for longer periods of time. This is effective for generalized or focal seizures, and is the mechanism of medications such as valproate

Valproic acid

Valproic acid is a chemical compound that has found clinical use as an anticonvulsant and mood-stabilizing drug, primarily in the treatment of epilepsy, bipolar disorder, and, less commonly, major depression. It is also used to treat migraine headaches and schizophrenia...

and gabapentin

Gabapentin

Gabapentin is a pharmaceutical drug, specifically a GABA analogue. It was originally developed for the treatment of epilepsy, and currently is also used to relieve neuropathic pain...

. Sodium channels are typically targeted for the prevention of focal seizures. This is accomplished by lengthening the refractory period, during which the channels are inactive, and as such eliminating the ability of the neuron to fire rapidly in succession. Medications that affect this pathway include Carbamazepine

Carbamazepine

Carbamazepine is an anticonvulsant and mood-stabilizing drug used primarily in the treatment of epilepsy and bipolar disorder, as well as trigeminal neuralgia...

and Lamotrigine

Lamotrigine

. Calcium channel

Calcium channel

A Calcium channel is an ion channel which displays selective permeability to calcium ions. It is sometimes synonymous as voltage-dependent calcium channel, although there are also ligand-gated calcium channels.-Comparison tables:...

s can be blocked according to their subunits, specifically targeting T-calcium channels. Ethosuximide

Ethosuximide

Ethosuximide is a succinimide anticonvulsant, used mainly in absence seizures.-Approved:It is approved for absence seizures. Ethosuximide is considered the first choice drug for treating absence seizures in part because it lacks the idiosyncratic hepatotoxicity of the alternative anti-absence...

works in this manner, and it is effective against absence seizures. The final pathway involves blocking excitatory glutamate receptor, namely AMPA

AMPA

AMPA is a compound that is a specific agonist for the AMPA receptor, where it mimics the effects of the neurotransmitter glutamate....

and NMDA. This effectively decreases the probability that a presynaptic action potential will produce an action potential

Action potential

In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...

in the postsynaptic neuron. Drugs utilizing this mechanism are effective, but no drug currently in use acts solely on this pathway. Some examples include diazepam and valproate

Valproic acid

Surgical Treatment

When both the amount and severity of seizures becomes uncontrollable and seizures remain resistant to the various anticonvulsants, a patient most likely will be considered for a frontal lobectomy
Lobectomy
Lobectomy means surgical excision of a lobe. This may refer to a lobe of the lung, a lobe of the thyroid , or a lobe of the brain ....

. This procedure involves the removal of focal regions of the frontal lobes that have been identified as being problematic for the patient. It has been found that around 30% to 50% of patients that undergo a frontal lobectomy will forever be free from seizures that cause a loss of consciousness

Consciousness

Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...

or cause abnormal movements.

If on the other hand, the seizures occur in an area that is too vital to remove (such as areas that control motor, sensory or language functions), then the surgeon will perform a procedure known as a multiple subpial transection
Multiple subpial transection
In the treatment of epilepsy, if partial seizures originate in areas of the brain that cannot be removed safely, multiple subpial transections are an alternative. The surgeon makes a series of shallow cuts into the brain's cerebral cortex...

. This procedure involves making a series of cuts that surround the focal region where the seizures have originated. By making cuts surrounding the focal region, the surgeon is able to isolate that specific section of the brain and prevent electrical impulses from being able to travel horizontally to other areas of the brain.

The last surgical procedure that can be done to help prevent the reoccurrence of seizures in the frontal lobes is to implant a stimulator on the vagus nerve

Vagus nerve

The vagus nerve , also called pneumogastric nerve or cranial nerve X, is the tenth of twelve paired cranial nerves...

. This device is a self-activating device that is inserted directly under the skin and can be controlled directly by the patient. When a patient is feeling the onset of an aura

Aura (symptom)

, he/she can activate the stimulator which in turn will provide stimulation to the left vagus nerve (the left vagus nerve is used because the right nerve plays a role in cardiac function). Although little is understood about the exact mechanism for vagal nerve stimulation, it has been proven to be a successful treatment that can often terminate seizures before they begin.

Diet

The use of a regimented diet is an approach that has been found to help control seizures in children with severe, medically-intractable frontal lobe epilepsy. Although the use of dieting to prevent seizures from occurring is a lost treatment that has been replaced by the use of new types of anticonvulsants, it is still recommended to patients to this day. A ketogenic diet

Ketogenic diet

The ketogenic diet is a high-fat, adequate-protein, low-carbohydrate diet that in medicine is used primarily to treat difficult-to-control epilepsy in children. The diet mimics aspects of starvation by forcing the body to burn fats rather than carbohydrates...

is a high-fat, low-carbohydrate

Carbohydrate

A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...

based diet that patients are typically asked to follow in conjunction with their anticonvulsant medications. This diet was designed in order to mimic many of the effects that starvation has on the metabolic functioning of the body. By limiting the amount of carbohydrates and increasing the amount of exogenous fats available to the metabolism

Metabolism

Metabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...

, the body will create an excess of water-soluble compounds known as ketone bodies

Ketone bodies

Ketone bodies are three water-soluble compounds that are produced as by-products when fatty acids are broken down for energy in the liver and kidney. They are used as a source of energy in the heart and brain. In the brain, they are a vital source of energy during fasting...

. Although the mechanism of action is still unknown, it is believed that these excessive amounts of ketone bodies become the brain's main source of energy and in turn are able to suppress the frequencty of seizure occurrence.

Importance of Neuroimaging

Once anticonvulsant medications prove to be no longer effective and a patient is selected to undergo resective epilepsy surgery, the doctors must begin the surgical process by first identifying the epileptogenic zone. The removal of the epileptogenic zone, the area of brain tissue that is responsible for the generation of seizures, can lead to a reduction or freedom in the amount of seizures. One of the major concerns for surgeons before they operate on patients that have intractable epilepsis is to not only be able to pinpoint the epileptogenic zone that is to be removed but to also map out the localized regions surrounding the focal area that are associated with somatosensory, cognitive and motor functions. Through the use of neuroimaging devices such as fMRIs

Functional magnetic resonance imaging

Functional magnetic resonance imaging or functional MRI is a type of specialized MRI scan used to measure the hemodynamic response related to neural activity in the brain or spinal cord of humans or other animals. It is one of the most recently developed forms of neuroimaging...

, PET scans

Positron emission tomography

Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...

and SPECT scans

Single photon emission computed tomography

Single-photon emission computed tomography is a nuclear medicine tomographic imaging technique using gamma rays. It is very similar to conventional nuclear medicine planar imaging using a gamma camera. However, it is able to provide true 3D information...

doctors are now able to identify the exact positions of the lesions causing the seizures and can map out the sensorimotor, language, visual and memory functional locations in the frontal lobes of the brain prior to the resective surgery. Therefore structural and functional neuroimaging techniques help to fulfill two major goals: localiztion of the epileptogenic zone and the determination of the etiology producing the seizure. Prior to the invention of neuroimaging techniques, surgeries to eliminate frontal lobe seizures from occurring were very rare and not very successful. However the ability to localize the epiletogenic zone and the specific etiology for the seizures has made frontal lobe resective surgery just as successful as that for temporal lobe resective surgery.

Resective Surgery using Gamma-Knife Radiosurgery

Over the past decade or so, researchers have been attempting to discover less invasive, safer and more efficient technologies that enable surgeons to remove epileptogenic focal zones without causing any damage to neighboring cortical areas. One such technology that has emerged and has great promise, is the use of gamma knife radiosurgery

Radiosurgery

Radiosurgery is a medical procedure that allows non-invasive treatment of benign and malignant tumors. It is also known as stereotactic radiotherapy, when used to target lesions in the brain, and stereotactic body radiotherapy when used to target lesions in the body...

to either excise a brain tumor or repair a vascular malformation.

In Gamma Knife radiosurgery, intersecting gamma radiation beams are applied directly to the tumor site or vascular malformation site that had been established using neuroimaging. Although each beam itself is not strong enough to damage brain tissue, when the beams interesect they are strong enough to destroy the specific brain tissue that is to be excised. This process is extremely efficient and entirely non-invasive and is therefore much safer than actual neurosurgery itself.

Recently researchers and surgeons alike have begun to use Gamma Knife radiosurgery to treat cases of epilepsy by removing tumors responsible for causing the seizures. The early success rates in being able to alleviate seizures seem to be similar to those of temporal resective surgery however Gamma Knife radiosurgery has less associated risk factors. Current research on this topic is aimed at improving the technique in order to increase success rates as well as developing non-invasive forms of physiologic monitoring in order to determine the epileptogenic focus conclusively.

External links

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Anatomy of Frontal Lobe Cortex

Precentral Cortex

Prefrontal Cortex

Symptoms

Common Misdiagnoses

Causes

Frequency

Social Impacts and Quality of Life

Treatments

Medications

Chemical Pathways for Anticonvulsants

Surgical Treatment

Diet

Importance of Neuroimaging

Resective Surgery using Gamma-Knife Radiosurgery

See also

External links