Intro to Sensation and Perception

Module 2 Section 2

Nuts and Bolts First

Sensation: process by which we receive incoming information and stimulus from the environment.

Perception: process by which we organize and interpret that stimulus.

I see this…

I perceive it as a pile of tasty little nuggets of pumpkiny goodness.

Kindergarten Review Time:

We all know our senses, but what other senses are out

there…

We all know our senses, but what other senses are out

there…

We all know our senses, but what other senses are out

there…

Bottom Line on Senses…

Humans and animals have different absolute thresholds for sensations.

The minimum stimulus needed to detect that stimulus 50% of the time.

A ‘different’ ThresholdI am writing this to you today, in order to illustrate

the concept of difference threshold. It is not like

absolute threshold, so don’t confuse the two. Difference

threshold is the minimum difference in stimulus required for

you to detect a change. It is the ‘just noticeable difference’.

It is hard to understand when reading because your

eyes, when you follow directions, adjust to the next

level of text without noticing a change.

It does take a while for your sense of sight to say,

“hey, something is not right here”.

Smelly Shoe Experiment

Try an experiment like this the next time you go over to someone’s house.

When you go somewhere that has a strange smell, note how long it takes for that smell to “go away”.

Sensory adaptation: the lowering of sensitivity of a sense the longer you are exposed to it.

Selective Attention

We can not possibly perceive every single sensory stimulus that comes our way.

It is estimated that we encounter around 11,000,000 bits of information every second.

Actively process 40!

Stimulus Overload

Try to find what changes in each picture in the fewest number of flashes.

Amazing Selective Attention Demo

http://viscog.beckman.illinois.edu/djs_lab/demos.html

You must be blind…kind of.

A classic example of selective attention with our senses is the concept of change blindness.

Change blindness is the failure to see something change right in front of your eyes.

Change blindness video change tie

How the Senses Work Together Our senses work

together as interdependent agents.

For Example: Smell and vision help

taste.