MRI and Brain Function Study

MRI & Brain Imaging

• MRI uses strong magnetic fields to align the spins of protons in hydrogen atoms in the brain, creating a static image.
• By capturing many snapshots, MRI can create 2D slices or 3D models of the brain.
• The structure of the brain can be studied via MRI, allowing for comparisons of grey matter density before and after learning.

Localization of Brain Function

• Specific brain areas have functions associated with specific behaviors.
• Although certain areas have specialized functions, they collaborate with other regions to produce complex behaviors.
• The medial temporal lobe plays a role in visual memory.

Dragansky's Juggling Study

• This study investigated brain changes after learning a motor skill (juggling).
• 24 non-juggler volunteers were divided into jugglers (learned juggling) and non-jugglers (control).
• Jugglers had MRI scans at the start, after mastering juggling, and three months later.
• Non-jugglers had scans only at the beginning and the end.

Results of Dragansky's Study

• Learning juggling induced structural changes in the brain, particularly in areas related to the learned skill.
• Changes were localized in the medial temporal lobe (MTL), suggesting this area's role in visual memory processing.
• Findings support the idea of localized brain function, despite the likely activation of other brain areas during learning.

Neuroplasticity & Brain Changes

• The brain adapts to environmental changes through neuroplasticity.
• One way it changes is through the creation of neural networks, facilitated by long-term potentiation and the repeated firing of neurons.
• This increases dendritic branching and the number of synapses.
• Another change is neural pruning, reducing the number of synapses through dendritic branch removal.
• Pruning is caused by neuron cell death, hormones like cortisol, or the lack of use of a neural pathway.

Dragansky's Study & Neural Pruning

• This study showed that unused neural pathways can be pruned.
• Participants in the juggling group showed an increase in grey matter in the mid-temporal area associated with visual memory after learning juggling.
• Three months after stopping juggling, grey matter in these areas decreased, indicating pruning.

Biological Approach & Experimentation

• Psychologists in the biological approach use experiments to understand the brain-behavior relationship.
• Experiments manipulate an independent variable (IV) to observe its effect on the dependent variable (DV) while controlling other factors.
• In Dragansky's juggling study, the IV was learning juggling, and the DV was brain changes measured using MRI.
• Participants were randomly assigned to juggling and control groups.

Explore the fascinating world of MRI and its applications in brain imaging. This quiz delves into how MRI captures brain structure and function, and discusses the findings of Dragansky's juggling study, highlighting changes in brain activity from learning new skills. Test your knowledge on the relationship between brain regions and behavior.