1. Neuroscienceas a Basis for Adult Development 1 of 26
2. The Neuroscience Approach2 of 26 3. The Neuroscience Approach
Learning Objectives How do the basic developmental forces benefit
from the neuroscience approach? What is the major focus of the
neuropsychological approach to neuroscience? Describe the
difference between the correlational approach and the activation
imaging approach to studying neuroscience. What is the difference
between MRI and fMRI scanning? 3 of 26 4. The Neuroscience Approach
Implications of the Developmental Forces Age is not the best
predictor of behavior. Behavior is determined by multiple forces.
Cognitive - Social Emotional Structural changes in brain volume and
density Functional changes in brain areas Brain plasticity
Environmental interventions on structure and activation of the
brain Social, biological, and psychological interventions to
influence positive changes 4 of 26 5. The Neuroscience Approach
Neuroscience Tools Magnetic resonance imaging (MRI) Functional
magnetic resonance imaging (fMRI) MRI provides static snapshots of
the brain fMRI monitors dynamic activities of the brain concurrent
with behavioral performance Allows study of age related pathologies
Alzheimers Parkinsons 5 of 26 6. The Neuroscience Approach
Neuroscience Perspective Methodological Perspectives
Neuropsychological Compares healthy older adults with those with
pathologicaldisorders of the brain Correlational Links measures of
cognitive performance to measures ofbrain structure or functioning
Activation imaging Links functional brain activity with cognitive
behavior data6 of 26 7. Neuroscience & Cognitive Aging 7 of 26
8. Neuroscience and Cognitive Aging Learning Objectives What are
the basic structural changes in the brain as we age? What cognitive
functions are associated with volume shrinkage in the aging brain?
How do decreases in the dopaminergic system relate to changes in
cognitive functioning as we grow older? What happens to brain
activation as we age? What are the cultural implications of
neuroimaging? How does bilateral activation serve a functional role
in older adults cognitive functioning? What are the major
differences between the HAROLD and STAC models of brain activation
and aging? 8 of 26 9. Neuroscience and Cognitive Aging Structure of
the Brain Anatomy of the human brain Executive functions Ability to
make and carry out plans Switch between tasks Maintain attention
and focus Age-Related Changes in the Structure of the Brain
Thinning and shrinkage in volume and density White matter
hyperintensities (WMH) Indicates myelin loss or neural atrophy
Diffusion tensor imaging (DTI) Index of density or structural
health of the white matter9 of 26 10. Neuroscience and Cognitive
Aging Structure of the Brain How deteriorating structural changes
relate to cognitive function Less efficient information processing
Speed of processing Executive functions Declarative long-term
memory Volume shrinkage in the brain linked to: Lower cognitive
test scores Poor performance of executive function which is also
linked to: Decreased volume of prefrontal cortex Memory decline
Frontal volume as predictor of cognitive function has yielded
inconsistent findings. 10 of 26 11. Neuroscience and Cognitive
Aging Structure of the Brain Studies in structural changes in the
aging brain and cognitive functions has overall produced
inconsistent findings. However, inconsistencies can be attributed
to: Sample composition Whether cross-sectional differences or
longitudinalchanges are being examined Whether different subregions
are under investigation Whether different cognitive test are used
Regardless, when longitudinal converge with cross-sectionalstudies,
it is clear that increases in WMH are associated withreduced
performance on executive functioning tasks. 11 of 26 12.
Neuroscience and Cognitive Aging Age-Related Changes in
Neurochemical Properties The dopaminergic system is associated
with: Higherlevel cognitive functioning Inhibiting thoughts
Attention Planning Declines in dopamine system are related to
declinesin: Episodic memory Speed tasks Age-related deficits in
working memory Declines in memory 12 of 26 13. Neuroscience and
Cognitive Aging Age-Related Changes in Brain Activity Functional
imaging (fMRI) examines how: Changes in brain activity are related
to: Changes in task demands Type of cognitive functioning under
investigation Do older adults compared to younger adults
usedifferent areas of the brain in order to performcognitive tasks
more effectively? Is this a method of adaptive accommodation by the
brain inorder to assist older adults to adjust to
neurologicalimpairment brought about by increasing age?13 of 26 14.
Neuroscience and Cognitive Aging Functional Consequences of Brain
Deterioration Anterior cingulate cortex (ACC) Affiliated with the
prefrontal cortex and is also involved inexecutive control Reduced
working memory performance is related to decreased activation of
the ACC in older adults. Reduced brain activation
(under-recruitment) of the prefrontal cortex occurs during
intentional cognitive processing. Reduced frontal recruitment in
aging is context-dependent. Other studies show equal frontal
activity in older and younger adults in memory retrieval.14 of 26
15. Neuroscience and Cognitive Aging Culture, Neuroimaging, and
Aging Examining cultural differences in neurobiological aging Older
adults in from Western cultures show significantlygreater
object-processing adaptation in the lateral occipitalcomplex,
relating visual processing, than older East Asians. Overall,
however, age-related changes seem to be moreprofound than cultural
effects. Different regions of the brain do not deteriorate evenly.
Prefrontal area is more prone to decay than, for example,
theamygdala (involved in emotional processing). 15 of 26 16.
Neuroscience and Cognitive Aging Compensation and Prefrontal
Bilaterality Studies show that, when presented with similar tasks,
younger adults exhibit focal, unilateral activity in left
prefrontal region and older adults exhibit bilateral activity (both
left and right prefrontal areas). Why? Is it compensation for
deterioration in older brains or is itinefficient inhibitory
mechanisms? Growing body of evidence supports the theory that
bilateralactivation in older adults plays a supportive role in
theircognitive function. (see fig, 2.2) 16 of 26 17. Neuroscience
and Cognitive Aging Compensation and Prefrontal Bilaterality STAC
(scaffolding theory of cognitive age) Default network theory holds
that when the cognitive demandsare made on the brain the default
network is suppressed. - Increased demand scaffolds increase areas
of the brain. HAROLD (hemispheric asymmetry reduction in older
adults. Suggests bilaterality is compensatory in older adult
withreduced cognitive ability CRUNCH (compensation-related
utilization of neural circuits hypothesis) This hypothesis is
similar to HAROLD but suggests additionalmechanisms at work of
aging brains over-utilizing other regionsin the left hemisphere on
demanding tasks before going to theright hemisphere.17 of 26 18.
Neural Plasticity & the Aging Brain18 of 26 19. Neural
Plasticity and the Aging Brain Learning Objectives How do animal
models contribute to our understanding of neural plasticity and
aging? What evidence is there for neural plasticity and aging? How
does aerobic exercise influence cognitive aging? 19 of 26 20.
Neural Plasticity and the Aging Brain Plasticity involves the
interaction between the brain and theenvironment and is mostly used
to describe the effects ofexperience on the structures and function
of the neural system. Neural stem cells (which give rise to new
neurons) persist in adultbrains and can generate new cells
throughout adulthood. Environmental enrichment Experiments with
aging mice showedthe increased number of newly generated neurons
after sessions oncomplicated mazes. 20 of 26 21. Neuroscience &
Socio-Emotional Aging 21 of 26 22. Neuroscience and Socio-Emotional
Aging Learning Objectives Are there differences in the brain for
cognitive versus socio-emotional functioning? What is the neural
circuitry responsible for enhanced memory for emotional
information? What are the neural underpinnings of the positivity
effect found in older adults?22 of 26 23. Neuroscience and
Socio-Emotional Aging Emotional Processing and the Brain
Information with high emotional significance is more likely to be
remembered than information that is emotionally neutral for both
older and young adults. Negative high-arousal information is:
automatic in nature linked to activation of the amygdala
interacting with thehippocampus Negative low-arousal information:
more activation of the prefrontal cortex-hippocampus networkis
necessary If the amygdala is damaged, arousing stimuli are not
attended.23 of 26 24. Neuroscience and Socio-Emotional Aging Aging
and Emotional Processing Younger and older adults process positive
and negative information differently. Older adults are more
motivated to derive emotional meaningfrom life and to maintain a
positive affect. As a result, older adults pay attention and
remember positivemore than negative information. Younger adults
tend to pay attention and remember negativemore that positive
information.24 of 26 25. Neuroscience and Socio-Emotional Aging
Neurological Recruitment Underlying the Positive Effect in Memory
Core emotional memory network consists of the: amygdala hippocampus
lateral orbitofrontal cortex In older adults, these areas are
relatively well preserved in emotional memory and correspond to
memory performance in both positive and negative items. In both
older and younger adults, the occipito-temporal regions
(specifically the fusiform gyrus) are used for successful encoding
of negative information. Positive information activates the
anterior prefrontal regions. Older adults show activation of the
medial prefrontal cortex and regions of the cingulate gyrus when
responding to positive information whereas younger adults do not.25
of 26 26. Neuroscience and Socio-Emotional Aging Neurological
Recruitment Underlying the Positive Effect in Memory The positivity
effect should be seen only when an individual has a high degree of
cognitive control resources. Older adults who are low in cognitive
resources show no positivityeffect. Young and old adults show
different brain activation when viewing faces with negative
emotional expressions. Young adults show increased activity in the
amygdala when viewingnegative emotional expressions compared to
older adults. Older adults do show increased activity in the
anterior cingulate gyruswhen viewing negative emotional
expressions. Research reveals the core emotional memory networks is
preserved with aging. Age differences are found in encoding
positive and negative information.26 of 26 27. The End27 of 26
