Biological Level of Analysis


At the most basic level of analysis, human beings are biological systems. Our cognitions, emotions and behaviors are products of the anatomy and physiology of our nervous and endocrine systems. Over the last few centuries, discoveries have shown that:

  • the nature of the nervous system is electrical in part (Galvani)
  • different areas of the brain carry out different functions (Broca)
  • small gaps exist between nerve cells that require the action of chemicals to carry neural transmissions across these gaps
  • hormones play an important role in our psychological functioning.

Since the 1960s, with the invention and development of brain imaging technologies (for example, CAT
(computerized axial tomography), PET (positron emission tomography), fMRI (functional magnetic resonance imaging)) it has become possible to directly study living brains in action as various tasks are performed, and to correlate specific areas of brain damage with specific changes in a person’s personality or cognitive abilities. Advances in psychopharmacology—the field of medicine that addresses the balance of chemicals in the brain—have led to the development of new medications for problems as diverse as depression, anxiety disorders and Alzheimer’s disease.

After Darwin published his theory of evolution through natural selection, animals came to be studied in order to shed light on human behavior. With the completion of the human genome project, the chimpanzee genome project, and with other species having the full structure of their DNA mapped, the contribution of genes to our cognitions, emotions and behavior is becoming better understood. Behavioral genetics takes the skills of biological analysis used to study the differences between species and applies these skills to studying individual differences in humans. These are the components at the biological level of analysis needed to understand our complex biological system and the psychological functions it supports.

General Learning Outcomes

1. Outline principles that define the biological level of analysis.
2. Explain how principles that define the biological level of analysis may be demonstrated in research.
3. Discuss how and why particular research methods are used at the biological level of analysis
4. Discuss ethical considerations related to research studies at the biological level of analysis.

Physiology and behavior
5. Explain one study related to localization of function in the brain.
6. Using one or more examples, explain effects of neurotransmission on human behavior.
7. Using one or more examples, explain functions of two hormones in human behavior.
8. Discuss two effects of the environment on physiological processes
9. Examine one interaction between cognition and physiology in terms of behavior. Evaluate two relevant studies.
10. Discuss the use of brain imaging in investigating the relationship between biological factors and behavior.
Genetics and behavior
11. With reference to relevant research studies, to what extent does genetic inheritance influence behavior?
12. Examine one evolutionary explanation of behavior.
13. Discuss ethical considerations in research into genetic influences on behavior.

Prezi: Localization of Brain Function
Prezi: Psychological Methods
Prezi: Sensory and Perception

Case Studies