1. Tools of Discovery and Older Brain Structures
Module 4
Tools of Discovery and Older Brain Structures

2. Tools of Discovery and Older Brain Structures The Tools of Discovery: Having Our Head Examined
4-1: HOW DO NEUROSCIENTISTS STUDY THE BRAIN’S CONNECTIONS TO BEHAVIOR AND MIND?
Scientists can selectively destroy or electrically, chemically, or magnetically stimulate the brain, using various techniques:
Lesion: Naturally or experimentally caused destruction of brain tissue
Electroencephalogram (EEG): An amplified recording of the waves of electrical activity sweeping across the brain’s surface, measured by electrodes placed on the scalp
PET (positron emission tomography) scan: A visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

3. Tools of Discovery and Older Brain Structures The Tools of Discovery: Having Our Head Examined
Brain Hacking: An electroencephalograph provides amplified tracings of waves of electrical activity in the brain.

4. Tools of Discovery and Older Brain Structures The Tools of Discovery: Having Our Head Examined
MRI (magnetic resonance imaging): A technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue
MRI scans show brain anatomy
fMRI (functional MRI): A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans
fMRI scans show brain function as well as brain structure
Figures 2.9–2.11

5. Tools of Discovery and Older Brain Structures The Tools of Discovery: Having Our Head Examined
MRI scan of a healthy individual (left) and a person with schizophrenia (right). Note the enlarged ventricle, the fluid-filled brain region at the tip of the arrow in the image on the right.

6. Tools of Discovery and Older Brain Structures Older Brain Structures
4-2: WHAT STRUCTURES MAKE UP THE BRAINSTEM, AND WHAT ARE THE FUNCTIONS OF THE BRAINSTEM, THALAMUS, RETICULAR FORMATION, AND CEREBELLUM?
Less complex brain in primitive vertebrates regulates basic survival functions.
More complex brain in advanced mammals (including humans) contain new brain systems built on the old.

7. Tools of Discovery and Older Brain Structures Older Brain Structures The Brainstem
Brainstem: Oldest and innermost region of the brain
Begins where the spinal cord swells as it enters the skull
Brainstem responsible for automatic survival functions
Medulla: The base of the brainstem
Controls heartbeat and breathing
The brainstem is a crossover point, where most nerves to and from each side of the brain connect with the body’s opposite side

8. The Brainstem and Thalamus
Figure 4.4
The brainstem, including the pons and medulla, is an extension of the spinal cord. The thalamus is attached to the top of the brainstem. The reticular formation passes through both structures.

9. Tools of Discovery and Older Brain Structures Older Brain Structures The Thalamus
The brain’s sensory control center
Located on top of the brainstem
Directs sensory messages to cortex
Transmits replies to the cerebellum and medulla

10. Tools of Discovery and Older Brain Structures Older Brain Structures The Reticular Formation
Involves nerve network running through the brainstem into the thalamus
Filters incoming stimuli and relays important information to other brain areas
Plays an important role in controlling arousal

11. Tools of Discovery and Older Brain Structures Older Brain Structures The Cerebellum
Aids in judgment of time, sound and texture discrimination, and emotional control
Coordinates voluntary movement and output and balance
Enables nonverbal learning and memory
These older brain functions illustrate how our brain processes and stores most information outside of awareness.

12. Tools of Discovery and Older Brain Structures Older Brain Structures The Limbic System
4-3: WHAT ARE THE LIMBIC SYSTEM’S STRUCTURES AND FUNCTIONS?
This neural system sits between brain’s older parts and its cerebral hemispheres
Neural centers includes amygdala, hypothalamus, and hippocampus
Is linked to emotions and drives
The Amygdala
Consists of two lima-bean-sized neural clusters in the limbic system
Linked to emotion

13. Tools of Discovery and Older Brain Structures Older Brain Structures The Limbic System

14. Tools of Discovery and Older Brain Structures Older Brain Structures The Limbic System
The Hypothalamus
Is a neural structure lying below (hypo) the thalamus
Directs several maintenance activities (eating, drinking, body temperature)
Helps govern endocrine system via the pituitary gland
Is linked to emotion and reward
The Hippocampus
Is a neural center located in the limbic system
Helps process explicit memories for storage

15. Brain Structures and Their Functions