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

Midterm Testing Tips

Strategies for Multiple Choice Exams

Effective test-taking strategies can improve performance on psychology exams. The following tips are designed to help students approach multiple choice questions with confidence and accuracy.

• Read each question slowly: Carefully consider what is being asked before looking at the answer choices.

• Answer what you know first: Tackle questions you are confident about to secure easy marks.

• Return to difficult questions: After answering the easier questions, revisit those that require more thought.

• Use process of elimination: Remove options that are definitely incorrect and focus on those most likely to be correct.

Nervous System Structure & Organization

Overview of the Nervous System

The nervous system is the body's primary communication network, responsible for transmitting information and coordinating actions. It is divided into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS).

• Central Nervous System (CNS): Composed of the brain and spinal cord. It interprets and stores information and communicates with the rest of the body.

• Peripheral Nervous System (PNS): Connects the CNS to limbs and organs. It is further divided into the somatic and autonomic nervous systems.

Divisions of the Peripheral Nervous System

• Somatic Nervous System: Transmits sensory information and controls voluntary movement of skeletal muscles.

• Autonomic Nervous System: Regulates involuntary body functions. It has two subdivisions:

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

  • Parasympathetic Division: Conserves energy and maintains body functions at rest.

Key Structures of the Central Nervous System

• Spinal Cord: Pathway connecting the brain and the peripheral nervous system; transmits information to and from the brain.

• Brain: Interprets and stores information, coordinates actions, and communicates with muscles, glands, and organs.

Features of the Cerebral Cortex

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

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

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

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

• Corpus Callosum: Large bundle of nerve fibers connecting the two hemispheres of the brain, allowing communication between them.

Major Lobes of the Cerebral Cortex

• 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; provides excellent temporal resolution but poor spatial resolution.

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

• Functional Magnetic Resonance Imaging (fMRI): Measures changes in blood oxygenation (BOLD signal) to infer brain activity; offers good spatial resolution.

• Transcranial Magnetic Stimulation (TMS): Non-invasive technique that uses magnetic fields to stimulate nerve cells in the brain.

Comparison of Imaging Techniques

Technique	Type	Temporal Resolution	Spatial Resolution	Main Use
CT	Structural	Poor	Moderate	Detecting injuries, tumors
MRI	Structural	Poor	High	Detailed anatomy
DTI	Structural	Poor	High	Mapping white matter tracts
EEG	Functional	High	Poor	Measuring electrical activity
fMRI	Functional	Moderate	High	Mapping brain activation
TMS	Functional	High	Moderate	Stimulating brain regions

Key Terms and Concepts

• BOLD Signal: Blood Oxygen Level Dependent signal measured in fMRI to infer neural activity.

• Temporal Resolution: How precisely a technique can measure changes over time.

• Spatial Resolution: How precisely a technique can localize activity within the brain.

Example Application

Functional imaging techniques such as fMRI are used in research to identify which brain regions are involved in specific cognitive tasks, such as language processing or memory retrieval.

Additional info: The notes infer standard definitions and applications for imaging techniques and nervous system divisions, as the original slides provide only brief points and diagrams.