Biological Psychology II: Nervous System Structure, Organization, and Brain Imaging

Lecture 4: Biological Psychology II

Outline

• Midterm Testing Tips

• Nervous System Structure & Organization

• Brain Imaging

Midterm Testing Tips

Strategies for Multiple Choice Exams

Effective exam strategies can improve performance and reduce anxiety during psychology assessments.

• Read each question slowly: Take time to understand what is being asked before considering the answer choices.

• Answer what you know first: Complete questions you are confident about before moving to more challenging ones.

• Return for a second pass: After finishing the first round, revisit questions you skipped or were unsure about.

• Use process of elimination: Remove options that are definitely incorrect to increase your chances of selecting the correct answer.

• Mark 'definitely no' and 'most likely yes': This helps prioritize which questions to focus on during review.

Nervous System Structure & Organization

Overview of the Nervous System

The nervous system is the body's primary communication network, responsible for processing sensory information and coordinating responses.

• Central Nervous System (CNS): Composed of the brain and spinal cord. It interprets and stores information, and communicates with muscles, glands, and organs.

• Peripheral Nervous System (PNS): Connects the CNS to limbs and organs. It transmits sensory information and controls movement.

Divisions of the Peripheral Nervous System

• Somatic Nervous System: Controls voluntary movements of skeletal muscles.

• Autonomic Nervous System: Regulates involuntary body functions. It is further divided into:

  • Sympathetic Division: Prepares the body for action (fight or flight).

  • Parasympathetic Division: Conserves energy and maintains body functions (rest and digest).

Central Nervous System: Brain and Spinal Cord

• Spinal Cord: Acts as a pathway connecting the brain and the peripheral nervous system.

• Brain: The control center for interpreting sensory information and directing responses.

Structures of the Cerebral Cortex

The cerebral cortex is the outer layer of the brain, involved in complex functions such as perception, thought, and decision-making.

• Gyri (singular: gyrus): Raised folds on the surface of the cortex.

• Sulci (singular: sulcus): Grooves or depressions between the gyri.

• Gray Matter: Contains neuron cell bodies and is involved in processing information.

• Corpus Callosum: A thick band of nerve fibers connecting the two hemispheres of the brain, allowing communication between them.

Major Lobes of the Brain

• Frontal Lobe: Associated with reasoning, planning, movement, and problem-solving.

• Parietal Lobe: Processes sensory information such as touch, temperature, and pain.

• Temporal Lobe: Involved in auditory processing and memory.

• Occipital Lobe: Responsible for visual processing.

Brain Imaging

Structural Imaging Techniques

Structural imaging allows visualization of the physical structure of the brain, aiding in the diagnosis of injuries and abnormalities.

• Computed Tomography (CT): Uses X-rays to create detailed images of brain structure.

• Magnetic Resonance Imaging (MRI): Uses magnetic fields and radio waves to produce high-resolution images of brain anatomy.

• Diffusion Tensor Imaging (DTI): A type of MRI that maps white matter tracts by tracking the diffusion of water molecules.

Functional Imaging Techniques

Functional imaging measures brain activity, showing which areas are active during specific tasks or in response to stimuli.

• Electroencephalogram (EEG): Records electrical activity of the brain via electrodes placed on the scalp. Good for measuring timing of brain activity (temporal resolution), but less precise for location (spatial resolution).

• Event-Related Potentials (ERPs): Specific changes in EEG in response to particular events or stimuli.

• Functional MRI (fMRI): Measures changes in blood oxygenation (BOLD signal) to infer brain activity. Offers good spatial resolution.

• Transcranial Magnetic Stimulation (TMS): Uses magnetic fields to stimulate or inhibit neural activity in targeted brain regions.

Comparison of Imaging Techniques

Technique	Measures	Temporal Resolution	Spatial Resolution
EEG/ERP	Electrical activity	Excellent	Poor
fMRI	Blood oxygenation (BOLD)	Poor	Excellent
CT	Brain structure	N/A	Good
MRI	Brain structure	N/A	Excellent
DTI	White matter tracts	N/A	Excellent

Key Terms and Definitions

• BOLD Signal: Blood Oxygen Level Dependent signal used in fMRI to detect brain activity.

• Contralateral Organization: Each hemisphere of the brain controls the opposite side of the body.

• Gray Matter: Regions of the brain rich in neuron cell bodies, involved in processing and cognition.

• White Matter: Composed of myelinated axons, responsible for communication between different brain regions.

Example Application

Functional imaging techniques such as fMRI are used in research to study which brain areas are involved in language, memory, and emotion. For example, increased BOLD signal in the hippocampus during memory tasks indicates its role in memory formation.

Additional info: The notes infer standard definitions and comparisons for imaging techniques and brain structures based on typical introductory psychology curriculum.