1 Psychology 304: Brain and Behaviour Lecture 2

2 Research Methods 1.What techniques do biological psychologists use to assess the structure and function of the nervous system? (continued)

3 1. discuss the goals and methods of CT, PET, fMRI, and EEG. By the end of today’s class, you should be able to:

4 3. Imaging  Allows researchers to observe the structure and function of the living brain.  Examples: What techniques do biological psychologists use to assess the structure and function of the nervous system? (continued)

5 Computerized tomography (CT): Computers are used to enhance X-ray images of the nervous system. Provides images of brain structure.

6 CT Scans (Single Slice and 3D)

7 Positron emission tomography (PET): Subjects are administered a radioactive substance, often attached to glucose. A scanner detects the radioactive substance, indicating where glucose consumption and physiological activity are greatest. Provides images of brain activity. Red and yellow indicate areas of high activity.

8 PET Scans (Single Slice)

9 Functional magnetic resonance imaging (fMRI): Magnetic fields are used to detect changes in oxygen flow. A scanner detects brain regions where oxygen is delivered at higher concentrations, indicating where physiological activity is greatest. Provides images of brain structure and brain activity. Red and yellow indicate areas of high activity.

10 fMRI Scans (Single Slice)

11 fMRI Scan (3D)

12 4. Recording  Allows researchers to record the electrical and magnetic output of the living brain.  Examples:  The small electrical charges and magnetic fields that nerve cells generate are measured using electrodes.

13 Electroencephalography (EEG): Electrodes, placed on the scalp, measure the electrical activity of a large number of nerve cells. Changes in EEG signals that are elicited by the presentation of sensory stimuli are referred to as sensory evoked potentials. Provides a measure of brain activity.

14 EEG Recordings Associated with Different States of Consciousness Beta waves Alpha waves Theta waves Delta waves

15 Sensory Evoked Potentials Presentation of visual stimulus

16 Image 1 Image 2 Image 3 EEG Recordings for Comatose Patients

17 Research Methods 1.What techniques do biological psychologists use to assess the structure and function of the nervous system? (continued)