James Parkinson discovered the disease that now bears his name in
1817. Parkinson’s disease is the fourth most common neurodegenerative
disorder seen in older adults (Berkow and Fletcher 1992). It involves
a progressive deterioration of the nigrostriatal dopaminergic system
(motor system) and is associated with the depletion of dopamine (neurotransmitter
involved with motor functions) in the basal ganglia (part of the brain
associated with the control and coordination of movement). The disease
also involves the erosion of the limbic system, cortical projections,
and midbrain. It is believed that Parkinson’s disease may be partially
the result of environmental toxins. It is estimated that around .02
percent of the general population develops this disease with as high
as 25 percent for those over the age of seventy-five (Lezak 1995).
It affects more men than women, rarely sets in before the age of thirty,
and is more prevalent in minority groups (Lezak 1995).A gene has been
linked to the disease. This gene is believed to be responsible for
the regulation of a protein called “synuclein.” This
protein is also found in the plaques of patients with Alzheimer’s
Symptoms of Parkinson’s Disease:
of the disease may initially be lateralized (on one side of the body)
and include: hand tremors that resemble pill rolling movements, drooling,
lack of facial expression, rapid onset of a resting tremor (tremor
involving several muscle groups that is apparent during rest but tends
to disappear during purposeful movement), and cogwheel rigidity (continual
rhythmical interruption of passive movement that presents as a slight
catch with each movement). Other symptoms include: akinesia (partial
loss of voluntary muscle movement, or slowed initiation of motor movement),
poor handwriting, bradykinesia (loss of voluntary muscle movement),
absence of arm swing when walking, postural abnormalities (stooped
posture or stiffness), joint pain, gait disturbances (disturbances
in the ability to walk, often using small shuffling steps), and retropulsion
(tendency to fall backwards) (Ayd 1995). The presence of dementia is
estimated to occur in 20 to 40 percent of Parkinson’s patients
(Snyder and Nussbaum 1998).
Cognitive Deficits Often Mimic Frontal Symptoms:
Cognitive deficits associated with Parkinson’s tend to mimic
frontal lobe damage. This is in part due to the wiring of the frontal
lobe. Our brains have five separate circuits or “loops” that
run subcortically between the frontal lobes and other major cortical
structures. In subcortical diseases such as Parkinson’s, the
frontal lobes and other cortical structures are damaged at the subcortical
level via these five circuits. As the disease progresses, frontal symptoms
such as poor executive planning and mental flexibility begin to be
more prevalent. The degeneration of these circuits would impair the
person’s ability to form a preparatory set or concentrate and
would result in rigid thinking. Attentional deficits are common, as
are deficits in working memory and verbal fluency. Immediate verbal
memory tends to diminish but can usually be triggered through association.
Visual memory, vocabulary, syntax, reasoning, and grammar tend to remain
intact (Cooper et al. 1991).
Depression Is Common in Parkinson’s Disease:
Depression is common in Parkinson’s patients, with a higher
incidence in patients suffering symptoms of pain associated with the
disease (Lezak 1995). Dopamine replacement therapy is almost the universal
treatment of the disease and patients are now surviving ten to fifteen
years with proper treatment (Lezak 1995). This still brings to the
forefront the realization of one’s mortality. A Parkinson’s
patient and many other patients suffering neurological disease must
negotiate thoughts of death on a daily basis. Existential therapy or
a strong spiritual faith can greatly assist the person suffering from
Parkinson’s disease in finding meaning in their lives and in
the disease process.
Parkinson-plus syndromes are difficult to distinguish from Parkinson’s
disease. This is a class of disorders that tend to mimic some of the
symptoms of Parkinson’s disease with a few minor distinctions.
These symptoms include: progressive supranuclear palsy (Steele-Richardson-Olszewski
syndrome), the multiple system atrophies (olivopontocerebellar atrophy),
striatonigral degeneration, Shy-Drager syndrome, and possibly corticobasal
ganglionic degeneration. The prevalence rates for these disorders are
low and are usually initially marked by disturbances in motor functions.
Most are not responsive to dopamine therapies, which helps distinguish
Parkinson-plus syndrome from Parkinson’s disease.
Progressive Supranuclear Palsy Symptoms:
This rare disorder is a subtype of a Parkinson-plus syndrome. Symptoms
often begin around the age of sixty and are usually symmetrical at
onset. Resting tremor usually occurs later in the disease process (Snyder
and Nussbaum 1989). Symptoms are similar to other symptoms that characterize
subcortical dementias but begin to mimic cortical dementias as symptoms
progress. Symptoms include motor dysfunction, emotional disturbances,
cognitive slowing, memory impairment, and executive dysfunction. Dysarthria
(difficulty in articulation) is often present earlier than normally
seen in Parkinson’s disease. Gait disturbance is also prevalent
early in the disease and negotiating stairs becomes difficult (Berkow
and Fletcher 1992). Other symptoms that are characteristics of the
disease include: difficulty looking straight up or down, facial spasticity,
and difficulty maintaining posture (Johnson et al. 1992). Dementia
usually occurs later in the disease. Although drastic drops in dopamine
levels mark the disease, symptoms usually respond poorly to dopaminergic
medications (medications that replace dopamine) and usually progress
faster than seen in Parkinson’s disease.There is significant
slowing in all mental processing, although accuracy usually remains
relatively intact early in the disease (Campbell 1989). Therefore it
has been postulated that memory is not as impaired as the timing mechanism
of memory (Lezak 1995). Deficits can also be noted in visual-spatial
abilities, visual tracking and scanning, hand-eye coordination, word
finding, and visual field discrimination. Falls are common, and there
is usually trouble in writing and eating. Blurring and double vision
are also common.Short-term memory difficulties are common but not to
the degree seen in dementia of the Alzheimer’s type. Apathy is
often present and irritability and depression are common (Lezak 1995).As
the disease progresses, movement rigidity, defective control of mouth
and neck muscles, drooling, and impassive facial expression become
prevalent. Treatment is limited to medications to ease the symptoms
Parkinsonism is not the same as Parkinson’s disease. Parkinson’s
disease refers to a specific disease entity, whereas parkinsonism refers
to a syndrome that consists of four motor signs. These four motor signs
are rigidity, tremor, postural abnormalities, and bradykinesia (slowing
in the execution of movements) (Snyder and Nussbaum 1998). Parkinsonism
is seen in Parkinson’s disease but is also seen in several other
Acquired Immunodeficiency Syndrome
AIDS dementia complex is progressive, with symptoms that mimic a subcortical
dementia. Initial signs usually center around memory problems, neuromotor
deficits such as tremor and ataxia, poor concentration, and impairment
in psychomotor speed. As the disease progresses, behavioral and mood
problems become prevalent and psychosis may set in (Ayd 1995). Symptoms
of aphasia, agnosia, and apraxia are usually absent during the first
stages of the disease (Welsh-Bohmer and Ogrocki 1998). This disorder
is easily diagnosed, but treatments are limited.
Multiple sclerosis or MS (disseminated sclerosis) is a common neurologic
disorder that affects over 300,000 Americans (sixty to three hundred
per 100,000 individuals). It usually affects people between the ages
of fifteen and fifty, and the average life expectancy after onset is
twenty to twenty-five years (Campbell 1989). It affects more women
than men, occurs more in temperate zones, and is more common in people
of Northern European heritage.
There are several subtypes of the disorder. These include: Balo’s
sclerosis, Schilder’s disease, Devic’s disease, central
pontine myelinolysis, and Marchiafava-Bignami disease. Multiple sclerosis
is a relapsing disease (Campbell 1989). Symptoms often occur, clear
up, and then reoccur. Symptoms may clear up for months or years before
recurring. There is also a progressive pattern in which symptoms never
completely clear up, but gradually or rapidly become worse.
Changes within the Brain:
Swelling of the brain and central nervous system followed by demyelination
marks multiple sclerosis. Demyelination is the loss of the protective
coating (myelin) on nerve fibers that act to speed up nerve impulses.
This results in scattering of well-demarcated sclerotic plaques throughout
the brain and spinal cord (Campbell 1989).Symptoms:The
cause of the disease is unknown. Initial symptoms usually include loss
of control of motor movements, weakness or numbness in one or more
limbs, and visual deficits. Other symptoms include: sensory deficits,
gait and balance difficulties, weakness, and cognitive changes. Only
20 to 30 percent of patients develop cognitive deficits sufficient
to label them as demented (Snyder and Nussbaum 1998).
When dementia is present, patterns mimic those seen in subcortical
dementias (movement disorders, cognitive slowing, executive dysfunction,
memory impairment, and mood and personality changes). Treatment options
include medications designed to treat the symptoms as they occur and
medications designed to modify the disease activity.
Let’s begin examining the subcortical diseases with a brief
overview of Binswanger’s disease is also called subcortical atherosclerotic
encephalopathy. Otto Binswanger first described the disease in 1894,
and it is the result of decreased blood flow to the brain, usually
occurring between the ages of fifty and sixty. It is associated with
hypertension and arterial wall thickening. The disease is associated
with axonal loss, lacunar infarcts, dilation of perivascular spaces
and loss of myelin (Welsh-Bohmer and Ogrocki 1998).Symptoms
of the Disease: Multiple symptoms associated with the disease
include: amnesia, cognitive deficits, episodes of stroke or seizure,
apathy, changes in personality and mood, language deficits, and gait
and motor difficulties (Ayd 1995). Symptoms are usually gradually progressive.
Wilson’s disease (hepatolenticular degeneration) is a rare,
inherited disorder. It affects the body’s ability to metabolize
copper. Wilson’s disease manifests itself as toxic levels of
copper are deposited in the brain tissue, liver, and other organs.
Prevalence rates are estimated at three in 100,000 individuals (Ayd
1995, 676). The disease is transferred to offspring through a recessive
gene on chromosome 13 and usually becomes symptomatic between the
ages of five and fifty, although it’s more common between the
ages of ten and twenty-five (Snyder and Nussbaum 1998).
Definitive symptoms of Wilson’s disease are the Kayser-Fleischer
ring (a greenish-brown pigmentation around the cornea of the eye)
and cirrhosis of the liver (Ayd 1995). Other symptoms include a mix
of psychiatric and neurological abnormalities including: emotional
and personality changes, parkinsonian symptoms, tremors, rigidity,
postural instability, cognitive deterioration, and dysarthria (slowness
or incoordination of speech-related muscles). Treatment focuses on
limiting the intake of copper and in taking measures to eliminate
copper from the system (Snyder and Nussbaum 1998).
Creutzfeldt-Jakob disease (spastic pseudosclerosis; cortico-striato-spinal
degeneration) is an extremely rare, progressive dementia (occurs in
one individual per one million per year worldwide) that is caused by
the transmission of a prion (Tabrizi et al. 1996). Prions are infectious
proteins that seem to lack DNA. In 1997 Dr. Stanley Prusiner won the
Nobel Prize for his discovery of prions. Creutzfeldt-Jakob disease
occurs two to three times more often in males and typically occurs
in the mid fifties (Campbell 1989). In this extremely rapidly progressing
disease, death usually occurs within a year after the onset of symptoms.
Symptoms include memory impairment, motor problems, hemiparesis (paralysis
of one side of the body), hemianopia (visual-field deficits mimicking
blind spots), dysarthria (speech impairment marked by weakness or slowness
of speech musculature), myoclonus (brief repetitive muscle contractions
stemming from the central nervous system), depression, seizures, and
behavioral and emotional problems (Ayd 1995). Welsh-Bohmer and Ogrocki
(1998) identify a triad of symptoms that aid in the diagnosis of the
disorder. These include: myoclonus, acute onset of dementia, and electroencephalogram
results showing general slowing of brain activity with occasional sharp
spikes. The slowly progressive form of the disease can be distinguished
from AD by noted changes in reflex and motor abnormalities (Tabrizi
et al. 1996). The disease is highly contagious, especially with direct
contact with infected brain tissue. There is no known treatment for
this disease, and it usually first affects the cerebellum, or lower
areas of the brain.
Diffuse Lewy Body Disease:
Diffuse lewy body disease is marked by lewy body degeneration throughout
the neocortex, limbic system, hypothalamus, and brainstem. Lewy bodies
are found in nerve cells and are more prevalent in pigmented brain
stem neurons. Lewy bodies are found in 5 to 10 percent of normal brains
of people over the age of sixty and in 10 percent of brains of people
diagnosed with Alzheimer’s disease (Ayd 1995). They are also
found in the brains of virtually all cases of people diagnosed with
Parkinsonism and lewy body dementia. The presence of lewy bodies does
not indicate the presence of the disease and the number present in
the brain does not correlate with the severity or duration of the disease
(Ayd 1995).Symptoms of dementia with lewy bodies include progressive
dementia coupled with severe rigidity and moderate Parkinson’s
symptoms. It has been postulated that the neurological findings may
be associated with degeneration in the areas where lewy bodies form.
Diffuse lewy body disease should be suspected if a rapidly progressive
dementia is present followed by rigidity, visual hallucinations, and
other features of Parkinson’s (Burkhardt et al. 1988).Diagnosis
of the DisorderDiffuse lewy body dementia affects both outer-brain
(cortical) and inner-brain (subcortical) structures. There seems to
be pathology within the brain that is similar to Alzheimer’s
disease in some cases (Katzman et al. 1995). Therefore, there are currently
two subtypes of the disorder identified. The first is called lewy body
variant of AD and the second is diffuse lewy body disease (Welsh-Bohmer
and Ogrocki 1998). Both types are marked by progressive cognitive decline
that interferes with normal social or occupational functioning. Memory
impairment may not be evident in the early stages of the disease but
becomes more apparent as the disease progresses. There is often impairment
in attention, visuospatial abilities, and other skills that are dependent
upon frontal-subcortical structures (Kaye 1998).
Symptoms Associated With The Disease:
Symptoms associated with diffuse lewy body disease include:
- Fluctuating cognition with pronounced variations in attention
- Spontaneous motor features of parkinsonism Recurrent
detailed and elaborate visual hallucinations (Kaye 1998; Perry et
- Frontal lobe impairments
- Slowing of motor functionsForgetfulness
(Wagner and Bachman 1996).
- Syncope (fainting)
- Repeated falls
loss of consciousness
- Systematic delusions
- Sensitivity to neuroleptic
- Hallucinations (Kaye 1998).
Kaye also notes that the diagnosis of dementia with lewy bodies is
less likely if there is history of strokes, focal neurologic signs
on imaging, or evidence that another physical illness or brain disorder
may be attributable to the symptom cluster.
Huntington’s disease is an inherited disease that begins in
middle adulthood. Erratic, involuntary muscle movements and progressive
memory and emotional deterioration mark the disease. It was originally
called Huntington’s chorea for the Greek word “chorea,” meaning
dance. This is a reference to the twisting, spastic movements associated
with the disease. This progressive disorder has been localized to a
genetic deficit on chromosome 4 (Huntington’s Disease Collaborative
Research Group 1993).
Areas of the Brain Affected:
The basal ganglia is usually the first structure affected by the disease.
Later the disease progresses to the frontal lobes where symptoms of
inattention and lack of motivation appear. Huntington’s disease
is classified as a frontal-subcortical disease (Joynt and Shoulson
in Heilman and Valenstein, eds. 1985). The disease goes largely untreatable
except for measures taken to ease the symptoms and discomfort.
disease is easily diagnosed and even predictable with blood tests,
given its genetic etiology. It is believed that the malformed Huntington’s
protein is formed into fibrils that represent the beta-amyloid plaques
seen in Alzheimer’s disease. Huntington’s disease affects
an estimated four to eight people in 100,000 and 50 percent of the
children of a parent with the disease will inherit it (Harper 1992).
Symptoms usually manifest themselves in adults between the ages of
forty and fifty and can last as long as twenty to thirty years. If
the disease is inherited from the mother, it tends to progress more
slowly and appear later in life than when it is inherited from the
Symptoms are variable but often mimic the progression of Parkinson’s
disease in their initial motor effects and eventual effects on frontal
lobe functioning. Cognitive deficits implicate the caudate nucleus
in its mental rather than its motor functions. Eye movements slow down
and become jerky (nystagmus). Other manifestations include slowed mental
processing, shortened attention span, poor concentration, inflexibility
in thinking, and slowed motor performance with the nondominant hand.
Motor learning is impaired and working memory becomes especially susceptible
to interference. Retrieval deteriorates as the disease progresses and
visuospatial functions remain impaired throughout the disease process.
Verbal functions (like speech comprehension, language processing) tend
to remain preserved until the later stages of the disease with the
exception of speech production (Welsh-Bohmer and Ogrocki 1998). Depression
is likely to accompany Huntington’s disease. Some initial presentations
initially involve psychiatric symptoms such as depression or symptoms
that mimic schizophrenia (Folstein et al. 1979).
Pick’s disease (also known as circumscribed cortical atrophy)
is named after the psychiatrist Arnold Pick (1851-1924) (Campbell 1989).
This disease is the most widely known subtype of frontotemporal dementia.
Its presentation is unique in that the first symptoms usually center
on strange behaviors, lack of judgment, and impulsiveness rather than
the memory problems seen in many other forms of dementia. Pick’s
disease is relatively rare, comprising only about 2 percent of dementia
patients, or less than one tenth of 1 percent of the general population
(Lezak 1995). Because cognitive functions are usually preserved early
in the illness, psychosis usually needs to be ruled out as a differential
diagnosis (Kaye 1998). The duration of the disease is usually between
two to seventeen years (Lezak 1995, 220).In this progressive dementia
involving the temporal and frontal lobes, symptoms are similar to other
disease processes involving the same anatomy. Early symptoms may involve
difficulties with attention, significant changes in personality and
emotion, and lack of motivation. Language disturbances usually involve
impaired verbal fluency and reduced conversational speech (Moss et
al. 1992). Personality and emotional changes are usually more pronounced
than seen in Alzheimer’s disease, although the severity of dementia
is usually not as prevalent.
Who Does It Affect and What Can We Do?
The average age of onset for Pick’s disease is fifty-five years
old (Campbell 1989). It affects more women than men, and there is a
strong correlation between developing Pick’s disease and having
a blood relative with the disease. Up to 60 percent of patients with
a frontotemporal dementia have a family history of the disease (Kaye
1998). Frontotemporal dementia has been linked to chromosome 17 and
is usually revealed in neuroimaging by atrophy (wasting) in the frontal
and anterior temporal lobes. SPECT scanning may reveal decreased cerebral
blood flow over the frontal lobes, which is a distinct finding for
this type of dementia (Kaye 1998). Treatment options are limited but
include cholinesterase inhibitors coupled with behavior modulating
medications, such as benzodiazepines, antidepressants, and/or neuroleptics.
This type of dementia occurs at about one-fourth the
rate of Alzheimer’s
disease (Lezak 1995). It is referred to by this name because the frontal
and anterior temporal lobes show localized atrophy (wasting) and upon
autopsy reveal a loss of neurons, astrocytosis (small tumors) with
intraneuronal inclusions (Pick bodies), and inflated neurons. Mutations
in the tau gene on chromosome 17 have been associated with a frontotemporal
dementia with parkinsonism (Poorkaj et al. 1998).
Key Features of Frontotemporal Dementia:
The frontal lobe (forehead region of the brain) is
responsible for the control of a number of behaviors that are referred
to as “executive
functioning.” Ogrocki and Welsh-Bohmer identify several features
of executive functioning that can be affected in disorders involving
the frontal lobes. These include: attention, planning, self-awareness,
abstraction, flexibility in thinking, self-regulation, behavior execution
and inhibition, decision making, changes in personality, and creativity
(2000, 23). In frontal-lobe dementias these functions are severe enough
to impair daily functioning.
Characteristics Unique to Frontotemporal Dementia (Kaye 1998):
- Insidious onset with slow progression
- Conduct and behavioral deficits
appearing early in the disease process
- Neglect of hygiene (Loss of personal awareness)
- Inappropriate social
- Disinhibition, impulsivity, and distractibility Excessive eating,
smoking, or alcohol consumption
- Pica (compulsive eating of items that
are not considered eatable)
- Changes in speech patterns Social withdrawal
- Perseverative (repetitious) or ritualistic behaviors
- Changes in speech output Echolalia (repeating what they have recently
- Stereotyped speech (constant repetition of phrases)
- Late mutism (progressive reduction of speech)
- Physical changesIncontinence
- Early or prominent primitive “frontal” reflexes
- Late akinesia, rigidity, tremor
Vascular dementia can affect either the cortical or subcortical areas of the brain. Its progression is fluctuating (step-like) rather than steady (hill-like) like some of the more progressive dementias. It was formerly referred to as “multi-infarct dementia” and is often associated with cerebral arteriosclerosis (thickening or hardening of the arterial wall). It is the result of a series of strokes, which have produced enough brain tissue damage to cause the onset of cognitive impairment. Infarct refers to an area of dead or dying brain tissue resulting from obstruction or destruction of the blood vessels that normally supply blood to that area. Vascular dementia accounts for about one fourth of progressive dementias (Tomlinson et al. 1970). Vascular findings are frequently seen with Alzheimer’s disease related cortical pathology (Welsh et al. 1996). There has been a correlation found between some forms of vascular dementia, AD, and the ApoE gene, which suggests possible shared physiology (Saunders et al. 1993).
Types of Vessel Disease:
Symptoms of Vascular Dementia:
- There are two types of strokes (also called cerebral vascular accidents or CVAs).
- An embolism is a clot or other obstruction that is carried from a larger vessel into a smaller one. It obstructs the circulation of blood and results in damaged tissue. A thrombosis is a formed clot that remains at the point at which it formed. A thrombosis typically involves a much slower progression than an embolism. Damage can also be in the form of softening of the brain tissue (encephalomalacia).
- Cerebral hemorrhage is a massive bleeding into the brain. This bleeding results in abrupt tissue damage and is often fatal. It is often the result of hypertension (high blood pressure). An aneurysm is a vascular dilation or swelling of blood vessels, which results from defects in the elasticity of the vessel wall (Kolb and Whishaw 1995).
- Single strokes usually result in much more localized or specific deficits than the more global vascular dementia, although a single stroke placed in the right area, such as the angular gyrus or anterior or paramedian thalamus, can mimic a multi-infarct’s dementing process (Kaye 1998). Strokes can also be transient and fleeting in nature. These small strokes are referred to as transient ischemic attacks (“mini-strokes”). Lateralized motor dysfunction (weakness, lack of coordination, or paralysis on one side of the body) and acute speech impairments are cardinal symptoms of vascular involvement. If this occurs to you or someone you know, seek medical help immediately.
- Symptoms are variable but can include: memory impairment, lateralized motor impairment, difficulties in walking, urinary incontinence, deficits in judgment, personality changes, and changes in impulse control (Campbell 1989). A common pattern seen in subcortical vascular dementias is language impairments marked by broken fluency in speech (Barr et al. 1992). In this type of symptom presentation, comprehension usually remains intact, as does the ability to name objects (Villardita 1993). Inefficient information processing and motor slowing are also common hallmarks of the disorder (Welsh-Bohmer and Ogrocki 1998). For a diagnosis of vascular dementia to be given, there is usually a noted deficit in memory and a deficit in one or two other cognitive domains.
- Researchers at the University of Kentucky are currently following over 600 nuns from the School Sisters of Notre Dame. The nuns undergo annual evaluations and have agreed to donate their brains for investigation upon death. Studies have shown a correlation between brain infarcts and the number of plaques and tangles within the brain (Snowdon et al. 1997). Heyman and associates (1998) demonstrated that patients with both a history of infarcts and AD showed more severe dementia than those patients with AD alone.