Questions: To generate a structural image of the human brain, researchers typically use: 1) magnetic resonance image (MRI) 2) electroencephalogram (EEG) 3) positron emission tomography (PET) 4) electromyogram (EMG)

The answer to Question 18 is the first one (1): magnetic resonance image (MRI).

Explanation for each option:

1. Magnetic Resonance Imaging (MRI): MRI is a non-invasive imaging technology that produces three-dimensional detailed anatomical images. It is often used for brain imaging because it provides high-resolution images of brain structures, making it ideal for generating structural images of the human brain.

2. Electroencephalogram (EEG): EEG measures electrical activity in the brain using electrodes placed on the scalp. It is primarily used to study brain function, such as detecting abnormalities in brain waves, rather than providing detailed structural images.

3. Positron Emission Tomography (PET): PET scans measure metabolic processes in the body by detecting gamma rays emitted indirectly by a tracer. While PET can provide some structural information, it is more commonly used to observe metabolic and functional processes in the brain.

4. Electromyogram (EMG): EMG measures muscle response or electrical activity in response to a nerve’s stimulation of the muscle. It is used to diagnose conditions affecting muscles and the nerves that control them, not for imaging brain structures.

Summary: To generate a structural image of the human brain, researchers typically use Magnetic Resonance Imaging (MRI) because it provides detailed and high-resolution images of brain anatomy.