Question 8: Chapter(s) 2; 6; 7
Discuss the relationship between normative brain aging
and information-processing, memory and intellectual
functioning during adulthood. (20)
Chapter 2
2.2: Neuroscience and Adult Aging Development
*What Age-Related Changes Occur in Neurons?
Several changes occur with age in neurons.
As we age, the number of neurons in the brain declines.
Structural changes include decreases in the size and number of dendrites, the development
of tangles in the fibers that make up the axon, and increases in the deposit of certain
proteins.
The number of potential connections also declines, as measured by the number of synapses
among neurons.
Interestingly, these same changes occur but in much greater numbers in diseases such as
Alzheimer’s disease, leading some researchers to speculate that there may be a link
between normal brain aging and pathological brain aging having to do with the speed and
number of changes, not in the kind of changes that occur.
*What Age-Related Changes Occur in Neurotransmitters?
Because neurons do not touch each other, much of the information transmission from one
neuron to another occurs chemically via neurotransmitters.
Advances have also been made in measuring changes in neurotransmitters in the aging
brain.
Dopamine Other Neurotransmitters
One neurotransmitter that has received The neurotransmitter serotonin is
a great deal of attention is dopamine. involved in several types of brain
Dopamine is a neurotransmitter processes, including memory, mood,
associated with higher-level cognitive appetite, and sleep.
functioning like inhibiting thoughts, Abnormal processing of serotonin has
attention, and planning, as well as been shown to be related to cognitive
emotion, movement, and pleasure and decline both in normal aging and in
pain. Alzheimer’s disease, as well as other
Collectively, the neurons that use disorders such as schizophrenia.
dopamine are called the dopaminergic Another important neurotransmitter
system. related to aging is acetylcholine. In the
For example, high dopamine levels are brain, acetylcholine has an important
linked to cognitive processing that is role in arousal, sensory perception, and
effortful and deliberate, but not to the sustaining attention.
processes that are more automatic and Damage to the brain structures that
less effortful. use acetylcholine is associated with
There is clear evidence that effective serious memory declines such as those
functioning of the dopaminergic system found in Alzheimer’s disease.
declines in normal aging.
, Exactly what does this mean?
Declines in the dopaminergic system
are related to declines in several
different aspects of memory, such as
episodic (short-term) memory and
memory for information acquired in
tasks that must be performed quickly,
and the amount of information that can
be held in mind at any given moment
(called working memory).
These are cognitive tasks that are
effortful and not automatic. Fewer age
differences are observed in more
automatic tasks, like judging the
familiarity of information.
Overall, the studies using neuroscience
methods to examine changes in the
dopaminergic system with increasing
age suggest that these changes play a
role in cognitive aging.
*What Age-Related Changes Occur in Brain Structures?
Our bodies undergo visible changes with age.
The brain is no exception.
Documenting those changes, however, has not been direct until the past decade.
As a result, the majority of studies examining structural changes in the brain as we grow
older have applied a correlational approach by employing postmortem analyses of adults’
brains.
More recently, researchers have been able to use cross-sectional and longitudinal designs to
examine age differences in the brain using brain imaging techniques.
In these studies, different regions of the brain are examined in terms of various structural
changes and deficiencies, such as thinning and shrinkage in volume and density, and the
declining health of the brain’s white matter, or white matter hyperintensities (WMH).
White matter refers to neurons that are covered by myelin that serve to transmit
information from one part of the cerebral cortex to another or from the cerebral cortex to
other parts of the brain.
White matter hyperintensities (WMH) are determined by the observation of high signal
intensity or a bright spotty such as neural atrophy.
Overall, postmortem and neuroimaging studies demonstrate that many changes occur with
age.
One important change is that considerable shrinkage occurs in the brain by late life.
However, this shrinkage is selective.
For example, the prefrontal cortex, the hippocampus, and the cerebellum show profound
shrinkage.
In contrast, the areas of the brain related to sensory functions, such as the visual cortex,
show relatively little shrinkage.
Discuss the relationship between normative brain aging
and information-processing, memory and intellectual
functioning during adulthood. (20)
Chapter 2
2.2: Neuroscience and Adult Aging Development
*What Age-Related Changes Occur in Neurons?
Several changes occur with age in neurons.
As we age, the number of neurons in the brain declines.
Structural changes include decreases in the size and number of dendrites, the development
of tangles in the fibers that make up the axon, and increases in the deposit of certain
proteins.
The number of potential connections also declines, as measured by the number of synapses
among neurons.
Interestingly, these same changes occur but in much greater numbers in diseases such as
Alzheimer’s disease, leading some researchers to speculate that there may be a link
between normal brain aging and pathological brain aging having to do with the speed and
number of changes, not in the kind of changes that occur.
*What Age-Related Changes Occur in Neurotransmitters?
Because neurons do not touch each other, much of the information transmission from one
neuron to another occurs chemically via neurotransmitters.
Advances have also been made in measuring changes in neurotransmitters in the aging
brain.
Dopamine Other Neurotransmitters
One neurotransmitter that has received The neurotransmitter serotonin is
a great deal of attention is dopamine. involved in several types of brain
Dopamine is a neurotransmitter processes, including memory, mood,
associated with higher-level cognitive appetite, and sleep.
functioning like inhibiting thoughts, Abnormal processing of serotonin has
attention, and planning, as well as been shown to be related to cognitive
emotion, movement, and pleasure and decline both in normal aging and in
pain. Alzheimer’s disease, as well as other
Collectively, the neurons that use disorders such as schizophrenia.
dopamine are called the dopaminergic Another important neurotransmitter
system. related to aging is acetylcholine. In the
For example, high dopamine levels are brain, acetylcholine has an important
linked to cognitive processing that is role in arousal, sensory perception, and
effortful and deliberate, but not to the sustaining attention.
processes that are more automatic and Damage to the brain structures that
less effortful. use acetylcholine is associated with
There is clear evidence that effective serious memory declines such as those
functioning of the dopaminergic system found in Alzheimer’s disease.
declines in normal aging.
, Exactly what does this mean?
Declines in the dopaminergic system
are related to declines in several
different aspects of memory, such as
episodic (short-term) memory and
memory for information acquired in
tasks that must be performed quickly,
and the amount of information that can
be held in mind at any given moment
(called working memory).
These are cognitive tasks that are
effortful and not automatic. Fewer age
differences are observed in more
automatic tasks, like judging the
familiarity of information.
Overall, the studies using neuroscience
methods to examine changes in the
dopaminergic system with increasing
age suggest that these changes play a
role in cognitive aging.
*What Age-Related Changes Occur in Brain Structures?
Our bodies undergo visible changes with age.
The brain is no exception.
Documenting those changes, however, has not been direct until the past decade.
As a result, the majority of studies examining structural changes in the brain as we grow
older have applied a correlational approach by employing postmortem analyses of adults’
brains.
More recently, researchers have been able to use cross-sectional and longitudinal designs to
examine age differences in the brain using brain imaging techniques.
In these studies, different regions of the brain are examined in terms of various structural
changes and deficiencies, such as thinning and shrinkage in volume and density, and the
declining health of the brain’s white matter, or white matter hyperintensities (WMH).
White matter refers to neurons that are covered by myelin that serve to transmit
information from one part of the cerebral cortex to another or from the cerebral cortex to
other parts of the brain.
White matter hyperintensities (WMH) are determined by the observation of high signal
intensity or a bright spotty such as neural atrophy.
Overall, postmortem and neuroimaging studies demonstrate that many changes occur with
age.
One important change is that considerable shrinkage occurs in the brain by late life.
However, this shrinkage is selective.
For example, the prefrontal cortex, the hippocampus, and the cerebellum show profound
shrinkage.
In contrast, the areas of the brain related to sensory functions, such as the visual cortex,
show relatively little shrinkage.
