Chapter 2 - Neuroscience Flashcards
Describe the 2 types of neuroimaging techniques and the value of each. Why are these techniques important?
Structural neuroimaging has the ability to provide highly detailed images of brain structures. Provides photos of anatomical structures at a specific point in time.
Helpful in identifying tumors and strokes. ex) MRI.
Functional neuroimaging does not provide high anatomical detail in imagines, though is effective in indicating brain structure activity. ex) fMRI.
These techniques are important bc they have demonstrated age-related changes in the brain as responsible for changes in performance. Has also led to effective interventions to enhance quality of life.
Compare & contrast 3 neuroscience perspectives and explain how they promote theoretical development in the field of aging.
The three perspectives are:
- neuropsychological approach
- neurocorrelational approach
- activation imaging approach.
The neuropsychological approach attempts to compare those with various pathological brain disorders with the brains of healthy aging adults. Looks to see if. damage in specific structures shows similar cognitive shortfalls as those aging healthily.
The neurocorrelational approach attempts to relate measures of cognitive performance to measures of brain structures and functioning. ex) correlating multitasking ability to brain volume. Drawback = findings are speculative.
The activation imaging approach attempts to connect neural activity with cognitive behavioural data. Relies on functional neuroimaging. Allows real-time investigation of changes in brain function as they affect cognitive performance.
Promotes theoretical development as these approaches can be used to test brain-behaviour theories. also demonstrate how changes in performance illustrate changes in brain.
Summarize the major age-related changes in brain structure, and describe how these changes have been linked to cognitive and emotional function. Be sure to include a description of white matter hyperintensities and diffusion tensor imaging.
A major age-related change that occurs in the brain is shrinkage. Certain areas of the brain over others demonstrate higher levels of shrinkage such as the hippocampus and the prefrontal cortex. This change in the hippocampus results in memory decline.
It has also been found that changes in the prefrontal cortex and amydala that occur with age may be linked to a decline in negative emotional processing and an increase in positive emotional processing. Brain pathologies can be observed as bright spotty appearances on images or as a high signal intensity, and are referred to as white matter hyperintensities(WMH). White matter declines as age increases. Diffusion tensor imaging (DTI) measures the direction and speed of water diffusion through the white matter. WMH are linked to cerebrovascular diseases.
Describe the age-related changes in neurons and neurotransmitters in brain neurochemistry and their relation to cognitive function. What are the functional consequences of brain deterioration?
Age-related changes in neurons can include:
• Decline in the number of neurons in the brain, thus the number of potential connections declines as well
• Decrease in number and size of dendrites
• Tangling in fibers that make up the axon
• Certain protein deposits increase
Age-related changes in neurotransmitters can include: • Functioning of the dopaminergic system declines and relates to the deterioration of episodic and working memory. • Cognitive decline in those with Alzheimer’s disease and normal aging has been related to abnormal processing of serotonin, which is involved in a variety of brain processes such as memory and mood. • Damage to structures that use acetylcholine is associated with serious memory deterioration.
What is neural plasticity? What are neural stem cells? Describe the evidence that supports plasticity. How do exercise and nutrition affect brain aging, and how are they related to plasticity?
Neural plasticity - the changes in the structure and functioning of the brain as the result of interaction between the brain and the environment
Neural stem cells are cells that persist in the adult brain and can generate new neutrons throughout the lifespan.
Findings that support plasticity remark that cognitive processes affected by aging can be improved through training.
Exercise has been shown to enhance brain plasticity and can even counter the declines in the hippocampus associated with Alzheimer’s.
Better cognitive functioning and greater brain volume was found as a result of B vitamins. This goes to show that nutrition plays a role in brain aging.
