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Файл:Развитие навыков переводческой деятельности на английском языке по теме «Нейропсихология». Учебно-методическое пособие
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Full Membership qualification for those who wish to be seen
to have achieved a recognized level of competence in the field.
A substantial number of people will have acquired this prior
to the end of 2003 through ‘grandparenting’ clauses, which
recognizes that they will have:
• been a Fellow, Associate Fellow or Graduate Member
of the BPS;
• been eligible to be a Chartered Clinical Psychologist or be a Full
Member of one of the BPS’s other divisions (but not the Division
of Teachers and Researchers in Psychology) with a background
relevant to clinical neuropsychology;
• been engaged in clinical neuropsychological practice for
a period of two years fulltime or its equivalent part-time.
(Clinical Neuropsychology: A Practical Guide to Assessment and
Management for Clinicians / ed. by L. H. Goldstein and J. E. McNeil)
Text 5
Neuroglia
Neurons and neuroglia are tightly packed in the CNS with spaces
no bigger than 20 nm between cells. There are about 10 neuroglial
cells for each neuron in the human brain and they make up about
half its volume (Parent, 1996). The neuroglial cells are supporting
cells and may be divided into two groups: macroglia comprising
astrocytes and oligodendrocytes, and microglial cells that function
like the debris removing macrophages in the periphery. In addition,
specialized cells called ependymal cells line the ventricles. However
glial cells, like neurons, also have intermediate forms that allow them
to respond to changes in their environment.
Astrocytes are the largest and most numerous of the glial cells. They
are starshaped with several processes extending into the surrounding
tissue. Astrocytes have an important role in maintaining
the stability of the CNS microenvironment. For example, astrocytes
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maintain adequate concentrations of potassium and glutamate
in the extracellular space, and they also play a role in maintaining
the blood-brain barrier. The oligodendrocyte has relatively few
processes, a smaller rounder nucleus and a smaller cell body than
the astrocyte. They are more numerous in the white matter than
astrocytes.
The oligodendrocytes form and maintain the myelin sheaths
surrounding axons. The myelin sheath facilitates the passage
of the action potential along the axon by having periodic interruptions
of the myelin sheath that are called the nodes of Ranvier.
Oligodendrocytes are also involved in active remyelination that
occurs in response to conditions when there is demyelination such
as in multiple sclerosis.
Microglial cells are found both in grey and white matter. They are
small in comparison with astrocytes, have elongated nuclei and wavy
processes with spine-like projections. Within the cerebral cortex about
10% of glial cells are microglial. Although they are generally inactive
in the normal adult brain, they have a role in responding to tissue
damage particularly due to inflammation or neurodegeneration.
The ependymal cells line the central canal of the spinal cord
and the ventricles of the brain. These specialized cells have mobile
hair-like structures called microvilli on their ventricular surface.
The surface layer of ependymal cells and the underlying astrocytes
make up a functional unit, the brain-cerebrospinal fluid interface.
Tight folding of the ependymal membrane into the ventricles form
the choroid plexuses, whose major role is to secrete cerebrospinal
fluid (CSF).
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(Clinical Neuropsychology: A Practical Guide to Assessment and
Management for Clinicians / ed. by L. H. Goldstein and J. E. McNeil)
Text 6
The Neural Tube
After fertilization, the cells of the embryo soon begin to become
specialized. The cells of the nervous system begin from the outer layer
of the embryo, called the ectoderm. This sheet of cells, the neural
plate, folds into a long hollow tubular structure, the neural tube.
The tail part becomes the spinal cord and the head region changes
shape so that three swellings emerge from the sides of the tube.
These swellings develop into the three major divisions of the brain:
the forebrain, which further develops into the cerebral hemispheres,
the midbrain and the hindbrain, which develops into the pons and
medulla oblongata.
The wall of the developing brain becomes progressively
thicker as cells proliferate, migrate to specific positions and mature
by forming specific connections. Cells migrate from the inner
surface of the neural tube to the outer part, where they aggregate
to form the cortical plate, and it is from this layer that the six
layers of the cerebral cortex develop. The cortical layers develop
in an inverted manner such that cells of the deeper layers (such
as layer VI) develop first. Cells in the superficial layers migrate
past older cells to reach their appropriate position. Neurons that
do not reach their appropriate position, or fail to make the correct
connections, will eventually die. The maturing primitive nerve
cell, called a neuroblast, does not establish synapses at random,
but is influenced in its dendrite and axonal growth by chemical
gradients so that synaptic contacts are made only with appropriate
post-synaptic neurons. Proteins have been identified that promote
the aggregation of neurons in selected areas, and different growth
factors, such as nerve growth factor, demonstrate how axons
find their way over large distances. Other factors may induce
neuroepithelial cells to differentiate into primitive glial cells,
called glioblasts, which in turn may form either oligodendrocytes
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or astrocytes. Glial cells, unlike neurons, may divide and increase
in number because of injury or disease.
(Clinical Neuropsychology: A Practical Guide to Assessment and
Management for Clinicians / ed. by L. H. Goldstein and J. E. McNeil)
Text 7
Cerebral Hemispheres
The cerebral hemispheres make up the largest part of the human
brain. Each hemisphere consists of a highly folded cortex of grey
matter that contains neurons, underlying white matter that contains
myelinated axons, resulting in a white appearance in fresh tissue,
and deep within the hemispheres are the basal ganglia (nuclei
of grey matter that contain neurons). The hemispheres are partially
separated by the longitudinal fissure. Each hemisphere is divided into
four lobes: frontal, temporal, parietal and occipital (mostly named
after the bones of the overlying skull). An outfolding of the cortex
is called a gyrus and an infolding a sulcus, or when deep and
prominent a fissure. About 70% of the cerebral cortex is hidden
within the depths of the sulci. On the lateral surface of the brain,
the lateral fissure separates the temporal lobe below from the frontal
and parietal lobes above. Within the depths of the lateral or Sylvian
fissure is a cortical area called the insula. The central sulcus, also
called the Rolandic sulcus, separates the frontal and parietal lobes.
The frontal lobes are the largest of all the lobes and extend from
the precentral gyrus. Behind the central gyrus lies the postcentral
gyrus, the area of the somatosensory cortex (part of the parietal lobe)
that has as its boundary with the occipital lobe the parieto-occipital
sulcus on the medial surface. The occipital lobe has no landmarks
on the lateral surface, but contains the prominent calcarine sulcus,
the primary visual processing area.
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(Clinical Neuropsychology: A Practical Guide to Assessment and
Management for Clinicians / ed. by L. H. Goldstein and J. E. McNeil)
Text 8
Neurodevelopmental and Perinatal Disorders
Disorders that occur during development of the nervous system
can be divided into several categories. Malformations occur
where there is a morphological defect of an organ or part of it,
because of an intrinsic cellular process. Neural tube defects are
characterized by abnormalities in the formation, growth and closure
of the anterior and posterior ends of the neural tube. A common
neural tube defect is spina bifida, caused by failure of the posterior
neural tube to close, while failure of the anterior tube to close
is associated with anencephaly. Disorders of migration include
heterotopias, where there is failure of neurons to migrate to their
appropriate cortical position, which can cause epilepsy. Where
there is an absence of sulci, as in lissencephaly, the normal cortical
lamination is altered, and commonly only four layers are present
instead of the usual six layers. Sporadic and hereditary forms
of agenesis of the corpus callosum are other migrational disorders.
Intrauterine infections may cause obstruction of the cerebral
aqueduct, resulting in congenital hydrocephalus. Displacement
of the brainstem to override the spinal cord is a malformation
referred to as the Arnold-Chiari malformation and may result
in increased intracranial pressure.
Exposure to certain chemicals during critical periods
of development may lead to malformations and delayed
development. Chemicals that have an adverse effect on development
are called teratogens. Maternal exposure to tobacco smoke may
result in an increase in neural tube defects, including spina bifida
and anencephaly, as well as increased mortality. Fetal alcohol
syndrome is observed in children of mothers who drink heavily
during pregnancy. Exposure of the fetus to alcohol is associated
with a number of anomalies including: growth retardation, facial
and cranial dysmorphias, microcephaly, neuronal migration defects,
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learning disabilities and neural tube defects. Other organ systems
are also, but less strikingly, affected.
Two common chromosomal abnormalities that cause learning
disabilities are Down’s syndrome and fragile X syndrome. Down’s
syndrome has an incidence of 1 in 600 to 1,000 live births. Trisomy
21 is present in over 90% of cases, and the risk of Down’s syndrome
increases with maternal age over 35 years. Several abnormalities
in the CNS may be present including: flattened occipital lobe,
decreased brain weight, narrow superior temporal gyrus, reduced
numbers of neurons and abnormalities in neuronal processes.
The neuropathology of Alzheimer’s disease is also often present
in persons over 30 years of age. There are also multiple defects
in other organ systems. The most common hereditary form
of learning disability is the chromosomal disorder fragile X syndrome.
A fragile site on the long arm of chromosome X has been identified,
but the genetic mechanisms resulting in the clinical phenotype
are not known. In affected males the brain is small and there are
abnormalities in dendrites and synapses, mild dysmorphic features,
enlarged testes and learning disabilities (Rudelli et al., 1985). About
one-third of affected females may have intellectual impairment.
Injury caused by mechanical trauma, metabolic disturbances
(including hypoxia) and intoxicating chemicals may occur at or near
birth. Perinatal brain injuries include haemorrhages and necrotic
lesions. Both extracranial and intracranial haemorrhages may be
encountered at autopsy. Of the intracranial haemorrhages, subdural,
subarachnoid, intracerebellar and intraventricular haemorrhages
have important clinical sequelae and may be life-threatening
in serious cases. Although about 80% of patients with a subdural
haemorrhage recover, the remainder have focal neurological
deficits and hydrocephalus. Intrauterine asphyxia may cause
cardiac output and circulatory insufficiency, resulting in reduced
oxygen supply to the brain (ischaemia) or reduced circulatory
transport (hypoxaemia). These perinatal injuries are associated with
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the development of permanent neurological impairment in some,
but not all, cases.
(Clinical Neuropsychology: A Practical Guide to Assessment and
Management for Clinicians / ed. by L. H. Goldstein and J. E. McNeil)
Text 9
The Contribution of Neuropscychology
to Child Evaluation
A distinction between clinical psychology and neuropsychology
can be made, although many aspects of education and training
overlap for these two specialty areas. A difference lies in the emphasis
in the science of neuropsychology on the study of brain-behavior
relationships and in the practice of neuropsychology on the application
of brain-behavior relationships to individual patients (Adams, 1996).
This concern with the linkage between behavior, or neurocognitive
function, and the brain substrate defines the field of neuropsychology.
Neuropsychologists are engaged in active exploration to authenticate
their impressions about brain function through hypothesis testing
at both an individual and broader level. This knowledge might
arise from clinical examination of an individual patient or from
experimental investigation of clinical or normal populations.
Age at injury and lesion severity continue to be the deserved
subject of many investigations due to the prominence of these
variables on outcome following brain insult. The idea that the earlier
the insult, the better the child will function cognitively is now
recognized as the myth that it is. Some outcome and longitudinal
studies of early focal lesions found less cognitive deficit than after
later focal lesions. It is also apparent that early diffuse lesions can
have pervasive effects, even more than later diffuse lesions.
The effects of closed-head injury (CHI) severity on cognitive
function appeared most apparent in children younger than 10 years
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old, although greater verbal learning and memory impairment was
found for adolescents with severe CHI than for the children. There
is also report of difficulty in acquiring reading skills after traumatic
brain injury (TBI) in the preschool population. Children with earlyage, severe TBI were more severely impaired in spatial learning and
orientation than older children. In general, and of related interest,
an imaging activation study finds that children demonstrate more
diffuse cognitive activity than adults.
Neuropsychological assessment is only one component
of neuropsychological practice. It provides standardized, objective, and
reliable measures of diverse aspects of human behavior, allowing for
the specification of each individual’s unique profile. With the addition
of unique qualitative data, a full assessment adds substantially to our
understanding of the child. Adult and child neuropsychology practice
require some similar, but also some different, skills. These are
described in comprehensive detail elsewhere (Baron, Fennell et al.,
1995). To summarize, brain-behavior relationships in a developing
child are both qualitatively and quantitatively different than those for
an adult. It is crucial that the child neuropsychologist be familiar with
the range of normal variation at each age level and be knowledgeable
about how to adjust his or her clinical impressions for the child’s
developmental stage. Such knowledge is essential if one is to avoid
misidentification of a normally developing child as one who is
impaired or developmentally delayed.
(Baron I. S. Neuropsychological Evaluation of the Child)
Text 10
Referrals from Family
Perplexing behavior, demonstrated at home or in other
environmental contexts but not observed at school, might lead
a parent to seek a neuropsychological evaluation. The evaluation is
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useful to examine neuropsychological integrity of function, primary
psychological factors, acquisition of developmental milestones
and level of maturity, or parenting skill effectiveness. It is sensitive
to deviations from expectation. For instance, an evaluation might
suggest a contributory seizure disorder, major mood disorder,
neurodevelopmental delay, or late effects of an acquired condition
such as an earlier traumatic brain injury. It might also highlight
the inconsistency between parents in setting limits on a child’s
behavior as contributing to the problem.
While not uncommon, discrepancy between parent and teacher
report requires clarification. Genuine differences might exist within
each setting, but often, parents and teachers view similar behaviors
quite disparately. The two very different settings can produce radically
different behavioral presentations. Factors such as subject area
proficiency, chronological age, class size, or the child’s temperament
affecting interpersonal relationships and learning style might influence
teachers’ perceptions. For example, a child with calculation weakness
might behave better in English than in mathematics class; a middle
school child’s disruptive behavior might be attributed to “raging
hormones” and inappropriately minimized; a child’s intrusive
behaviors might be better tolerated in a small class where there is
more one-to-one attention than in a large class that has no teacher
aides; or, an introverted, but learning-disabled, child might escape
notice while an assertive, but normally maturing, child’s antics might
bring unwarranted attention.
Additional modulating variables must be considered when
interpreting the child’s behavior in any setting. These include age,
family circumstances, and dynamics, cultural and socioeconomic
status; identifiable trauma or stressors, developmental maturity level,
medical status, general intelligence, and overall adaptive ability.
For instance, a young child might not easily respond to a teacher’s
demand to stay in her seat, follow the structure of set rules, or join
a group cooperatively. The child’s customary role within the family
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dynamic might be inappropriately transferred to the school setting.
A child living in poverty and a child from a wealthy family have
quite different experiential histories, and the associated cognitive
implications may vary. Emotional trauma cannot be easily blocked
from intruding once the child enters the classroom. Medical illness or
injury may result in school absence that further complicates the child’s
progress, and intellectual potential and emotional intelligence can
affect the ease of adaptability across different settings.
(Baron I. S. Neuropsychological Evaluation of the Child)
Text 11
Behavioral Assessment:
Intake Interviewing and Scheduling
The telephone intake interview for an outpatient evaluation helps
determine whether the referral is indeed appropriate. A clinician
needs to be assured that she can assess the child within proscribed
ethical responsibilities for psychologists that specify that one not
examine or treat outside the bounds of one’s own competence. Also,
she needs to determine that the referral is justified since it is a timeintensive and costly evaluation. While it is intended to add essential
information relevant to the child’s care, not all referrals are appropriate
nor should a referral be accepted just because it is recommended.
A parent needs to understand the procedures associated with
a neuropsychological evaluation and what the likely outcome will
be. It is helpful to explain the ways in which a neuropsychological
evaluation differs from other psychological evaluations and describe
the noninvasive techniques, domains to be assessed, time involved for
the one-to-one testing, and likely number of visits needed, along with
the purpose of the evaluation individualized for the referral reason.
Also, parents often need guidance about what to tell their child
prior to evaluation in preparation for the test session. The intake
interview provides this opportunity to assure parents that a simple
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