Frontal lobe disorder, also frontal lobe syndrome, is an impairment of the

frontal lobe The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove betwe ...

that occurs due to disease or

frontal lobe injury The frontal lobe of the human brain is both relatively large in mass and less restricted in movement than the posterior portion of the brain. It is a component of the cerebral system, which supports goal directed behavior. This lobe is often ci ...

. The frontal lobe of the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

plays a key role in

executive functions In cognitive science and neuropsychology, executive functions (collectively referred to as executive function and cognitive control) are a set of cognitive processes that are necessary for the cognitive control of behavior: selecting and succe ...

such as motivation, planning, social behaviour, and speech production. Frontal lobe syndrome can be caused by a range of conditions including head trauma, tumours,

neurodegenerative disease A neurodegenerative disease is caused by the progressive loss of structure or function of neurons, in the process known as neurodegeneration. Such neuronal damage may ultimately involve cell death. Neurodegenerative diseases include amyotrophic ...

Neurodevelopmental disorders Neurodevelopmental disorders are a group of disorders that affect the development of the nervous system, leading to abnormal brain function which may affect emotion, learning ability, self-control, and memory. The effects of neurodevelopmental ...

, neurosurgery and

cerebrovascular disease Cerebrovascular disease includes a variety of medical conditions that affect the blood vessels of the brain and the cerebral circulation. Arteries supplying oxygen and nutrients to the brain are often damaged or deformed in these disorders. Th ...

. Frontal lobe impairment can be detected by recognition of typical

signs and symptoms Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

, use of simple screening tests, and specialist neurological testing.

Signs and symptoms

The signs and symptoms of frontal lobe disorder can be indicated by

dysexecutive syndrome Dysexecutive syndrome (DES) consists of a group of symptoms, usually resulting from brain damage, that fall into cognitive, behavioural and emotional categories and tend to occur together. The term was introduced by Alan BaddeleyWilson, B.A., Evans, ...

which consists of a number of symptoms which tend to occur together. Broadly speaking, these symptoms fall into three main categories; cognitive (movement and speech), emotional or behavioral. Although many of these symptoms regularly co-occur, it is common to encounter patients who have several, but not all of these symptoms. This is one reason why some researchers are beginning to argue that dysexecutive syndrome is not the best term to describe these various symptoms. The fact that many of the dysexecutive syndrome symptoms can occur alone has led some researchers to suggest that the symptoms should not be labelled as a "syndrome" as such. Some of the latest imaging research on frontal cortex areas suggests that executive functions may be more discrete than was previously thought. Signs/symptoms can be divided as follows:

Causes

The causes of frontal lobe disorders can be

closed head injury Closed-head injury is a type of traumatic brain injury in which the skull and dura mater remain intact. Closed-head injuries are the leading cause of death in children under 4 years old and the most common cause of physical disability and cognitive ...

. An example of this can be from an accident, which can cause damage to the orbitofrontal cortex area of the brain.

Cerebrovascular disease Cerebrovascular disease includes a variety of medical conditions that affect the blood vessels of the brain and the cerebral circulation. Arteries supplying oxygen and nutrients to the brain are often damaged or deformed in these disorders. Th ...

may cause a

stroke A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...

in the frontal lobe.

Tumours A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

such as

meningiomas Meningioma, also known as meningeal tumor, is typically a slow-growing tumor that forms from the meninges, the membranous layers surrounding the brain and spinal cord. Symptoms depend on the location and occur as a result of the tumor pressing ...

may present with a frontal lobe syndrome. Frontal lobe impairment is also a feature of

Alzheimer's disease Alzheimer's disease (AD) is a neurodegeneration, neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in short-term me ...

, and

frontotemporal dementia Frontotemporal dementia (FTD), or frontotemporal degeneration disease, or frontotemporal neurocognitive disorder, encompasses several types of dementia involving the progressive degeneration of frontal and temporal lobes. FTDs broadly present as ...

Pathogenesis

The pathogenesis of frontal lobe disorders entails various pathologies, some are as follows: MRI of orbitofrontal cortex

Anatomy and functions

The frontal lobe contains the precentral gyrus and prefrontal cortex and, by some conventions, the orbitofrontal cortex. These three areas are represented in both the left and the right cerebral hemispheres. The

precentral gyrus The precentral gyrus is a prominent gyrus on the surface of the posterior frontal lobe of the brain. It is the site of the primary motor cortex that in humans is cytoarchitecturally defined as Brodmann area 4. Structure The precentral gyrus l ...

primary motor cortex The primary motor cortex (Brodmann area 4) is a brain region that in humans is located in the dorsal portion of the frontal lobe. It is the primary region of the motor system and works in association with other motor areas including premotor co ...

is concerned with the planning, initiation and control of fine motor movements dorsolateral to each hemisphere. The dorsolateral part of the frontal lobe is concerned with planning, strategy formation, and other

. The prefrontal cortex in the left hemisphere is involved with

verbal memory Verbal memory is a term used in cognitive psychology which refers to memory of words and other abstractions involving language. Verbal encoding Verbal encoding refers to the interpretation of verbal stimuli. Verbal encoding appears to be strongly ...

while the prefrontal cortex in the right hemisphere is involved in spatial memory. The left frontal operculum region of the prefrontal cortex, or

Broca's area Broca's area, or the Broca area (, also , ), is a region in the frontal lobe of the dominant Cerebral hemisphere, hemisphere, usually the left, of the Human brain, brain with functions linked to speech production. Language processing in the brai ...

, is responsible for expressive language, i.e. language production. The

orbitofrontal cortex The orbitofrontal cortex (OFC) is a prefrontal cortex region in the frontal lobes of the brain which is involved in the cognitive process of decision-making. In non-human primates it consists of the association cortex areas Brodmann area 11, 12 ...

is concerned with response inhibition, impulse control, and social behaviour.

Diagnosis

The diagnosis of frontal lobe disorder can be divided into the following three categories: * Clinical history Frontal lobe disorders may be recognized through a sudden and dramatic change in a person's

personality Personality is the characteristic sets of behaviors, cognitions, and emotional patterns that are formed from biological and environmental factors, and which change over time. While there is no generally agreed-upon definition of personality, mos ...

, for example with loss of social awareness, disinhibition, emotional instability, irritability or impulsiveness. Alternatively, the disorder may become apparent because of mood changes such as depression,

anxiety Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...

or apathy. * Examination On

mental state examination The mental status examination (MSE) is an important part of the clinical assessment process in neurological and psychiatric practice. It is a structured way of observing and describing a patient's psychological functioning at a given point in ti ...

a person with frontal lobe damage may show speech problems, with reduced verbal fluency. Typically the person is lacking in insight and judgment, but does not have marked cognitive abnormalities or memory impairment (as measured for example by the mini-mental state examination). With more severe impairment there may be

echolalia Echolalia is the unsolicited repetition of vocalizations made by another person (when repeated by the same person, it is called palilalia). In its profound form it is automatic and effortless. It is one of the echophenomena, closely related t ...

mutism Muteness or mutism () is defined as an absence of speech while conserving or maintaining the ability to hear the speech of others. Mutism is typically understood as a person's inability to speak, and commonly observed by their family members, caregi ...

Neurological examination A neurological examination is the assessment of sensory neuron and motor responses, especially reflexes, to determine whether the nervous system is impaired. This typically includes a physical examination and a review of the patient's medical hist ...

may show

primitive reflexes Primitive reflexes are reflex actions originating in the central nervous system that are exhibited by normal infants, but not neurologically intact adults, in response to particular stimuli. These reflexes are suppressed by the development of the ...

(also known as frontal release signs) such as the

grasp reflex Palmar grasp reflex (or grasp reflex) is a primitive and involuntary reflex found in infants of humans and most primates. When an object, such as an adult finger, is placed in an infant's palm, the infant's fingers reflexively grasp the object. ...

Akinesia Hypokinesia is one of the classifications of movement disorders, and refers to decreased bodily movement. Hypokinesia is characterized by a partial or complete loss of muscle movement due to a disruption in the basal ganglia. Hypokinesia is a sym ...

(lack of spontaneous movement) will be present in more severe and advanced cases. * Further investigation A range of neuropsychological tests are available for clarifying the nature and extent of frontal lobe dysfunction. For example, concept formation and ability to shift mental sets can be measured with the

Wisconsin Card Sorting Test The Wisconsin Card Sorting Test (WCST) is a neuropsychological test of set-shifting, which is the capability to show flexibility when exposed to changes in reinforcement.E. A. Berg. (1948). A simple objective technique for measuring flexibility in ...

, planning can be assessed with the Mazes subtest of the WISC.

Frontotemporal dementia Frontotemporal dementia (FTD), or frontotemporal degeneration disease, or frontotemporal neurocognitive disorder, encompasses several types of dementia involving the progressive degeneration of frontal and temporal lobes. FTDs broadly present as ...

shows up as atrophy of the frontal cortex on

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

. Frontal impairment due to head injuries, tumours or cerebrovascular disease will also appear on brain imaging.

Treatment

In terms of treatment for frontal lobe disorder, there is none, general supportive care is given, also some level of supervision could be needed. The prognosis will depend on the cause of the disorder, of course. A possible complication is that individuals with severe

injuries An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or o ...

may be disabled, such that, a

caregiver A caregiver or carer is a paid or unpaid member of a person's social network who helps them with activities of daily living. Since they have no specific professional training, they are often described as informal caregivers. Caregivers most commo ...

may be unrecognizable to the person. Another aspect of treatment of frontal lobe disorder is speech therapy. This type of therapy might help individuals with symptoms that are associated with

aphasia Aphasia is an inability to comprehend or formulate language because of damage to specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine but aphasia due to stroke is estimated to be 0.1–0.4% in t ...

and

dysarthria Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. In other words, it is a condition in which problems effectively ...

History

Phineas Gage, who sustained a severe frontal lobe injury in 1848, has been called a case of dysexecutive syndrome. Gage's psychological changes are almost always exaggeratedof the symptoms listed, the only ones Gage can be said to have exhibited are "anger and frustration", slight memory impairment, and "difficulty in planning".

References

External links

{{DEFAULTSORT:Frontal Lobe Disorder Neurobiological brain disorder Cognitive neuroscience Frontal lobe Mental disorders due to brain damage