Lesson Notes

Lesson 4.1a           Processing: Getting the Outside Inside

In this lesson you will learn how we sense information from our environment. Information that comes to us from the environment comes in different forms. For example, light comes to us in the form of light waves, and sound through sound waves. These electrochemical and mechanical vibrations respectively need to be transformed (transduction) into neural impulses that our brain can understand.

At any given moment we are bombarded with thousands of stimuli to interpret. Our brain will filter out all of these stimuli and allow us to attend to approximately forty at one time. This process, known as sensory reduction, enables us to function effectively. If you didn’t reduce your sensory information, you would be able to feel the heat coming through the vents in your house, while also hearing the buzz of the computer working, your heart beat, feel your feet touching the floor, your shirt on your shoulders, etc. ALL AT ONCE. As you can imagine, this would be overwhelming.

Lesson 4.1b Thresholds: Testing our Sensitivity

Psychologists trained in psychophysics study our ability to sense stimuli. What they have discovered is that we have an absolute threshold (minimum amount of stimulus to determine that it is present) and a difference threshold (minimum amount of stimulus needed to notice a change). In this lesson, you will read and understand their differences, as well as, explore the theory known as Weber’s Law.

Lesson 4.1c Adaptation: Weakening Our Sensitivity

This lesson teaches you how the human body has an amazing ability to adapt to the environment. The ability to adapt allows ours brain to focus its attention on more important incoming messages. But, we do not adapt to everything in our environment. Most notably, pain is something that humans do not adapt to. Pain is necessary for us to survive. Think about it, if you didn’t feel pain, you could cut yourself and not know that you need to get medical attention before it gets infected. Although, some people do not feel pain, for example athletes, through the release of endorphins, athletes can fight through their pain…at least for the short term.