Sensation and Perception

The Basics

• What is sensation?– Stimulation of sensory receptors and the

transmission of sensory information to the central nervous system.

-HUH?Sensory receptors are located along the spine and organs such as eyes and ears.

More BA6

• If that’s sensation Mr. Reardon, then what is Perception because I sure am lost.

• Perception– The psychological process through which we

interpret sensory stimulation– WHAT?

Components of Perception and Perception

• Absolute Threshold– The weakest amount of stimulus that can be

sensed.– Dog whistle example (see Jesse)– Can differ from person to person– This can effect the way we see the world

Components of Perception and Perception

• Difference Threshold– The minimum amount of difference between two

stimuli

– Stimuli need to be differentiated in order to distinguish what we need to hear versus noise

– Can my music people please pay attention to my next example?....Please?

Components of Perception and Perception

• Signal Detection Theory– A method that distinguishes stimuli that takes into

account not only strengths but also elements such as setting physical state and attitudes.

– Please pay attention to the following instruction

Components of Perception and Perception

• Sensory Adaption – The process by which we become more sensitive

to weak stimuli and less sensitive to unchanging stimuli

– Sounds of the country vs. Sounds of the city

Perception

• What is perception?– Remember your stories and many other

memories? How to you perceive them?

– Difference between Sensation and Perception?

– Why is this a major part of psychology?

It’s not you…….It’s me

• The first rule of perceptual organization is known as:

• Closure– The tendency to perceive a complete or whole

figure when there are gaps in what your senses tell you.

Oh, now I see it

• Figure ground perception– Perception of figures against their background.

– Look out the window tell me what you see?

– We see objects against the background

Rules of Organization

• 1. Proximity– People are influenced on how they perceive

objects based on the proximity of them.

– Take a look

Other Rules of Organization

• Similarity– People think of objects as being similar to each

other.

– See the Next Example

Other Rules of Organization

• Continuity– People see smooth continuous patterns rather

than disrupted ones

– See the Next Example

Other Rules of Organization

• Common Fate– When you see things moving together, you tend to

perceive them as belonging together.

Perception Activity

• Take a look at the following pictures and write down a gut response….you have 30 seconds to write three words to describe your feelings.

• Next we will go back to the picture to further interpret what is going on in the picture

• Next get with one partner and you each will describe what is go

Sleep and Dreams

• We are asleep an average of 1/3 of our lives.

• Why do we sleep, why do we dream

• Why do we experience nightmares

Clocks

• Circadian RhythmsThese are functions for how we live, or biological clocks.

• These rhythms include bodily changes such as body temp, blood pressure, and sleepiness.

• They usually operate on a 24-hour day schedule

• For example, your body temp is at its lowest between 3 and 5am everyday.

Clocks

• The most studies of these rhythms is that of a sleep wake cycle.

• We associate our days with clocks and light, when in reality we are living on this clock and given cues for when we should be asleep or awake.

• If this cycle is hindered, the clock expands to 25 hours.

Stages of sleep

• When we are fully awake we emit beta waves, which are short and quick.

• When we become drowsy and tired we go from beta to alpha waves.

This cycle includes flashing of images or colors and a sensation of falling.

Stages of Sleep

• The move to alpha waves leads us into stage 1

• Stage 1:Lightest sleepGo from Alpha to Theta wavesWe resemble vivid images and

sensations and if are awakened may seem like we were never asleep

Stages of Sleep

• We remain in stage 1 for 30-40 mins if not awakened.

• We move into stages 2,3, and 4Stages 3 and 4 are the deepest sleep

(delta waves) and is the hardest to wake someone up from.

Stages of Sleep

• After about a half hour of stage 4 sleep, we begin to return to level 3 quickly then 2 and finally 1.

• 90 mins will have passed since we fell asleep and something strange begins to happen to us.

• We breathe irregularly, blood pressure rises, heart beats faster, but it is not stage 1 but another stage of sleep….

REM

• Rapid Eye Movement– Beneath our closed lids our eyes are moving

rapidly – During a typical night of 8 hour sleep, most people

go through these stages up to 5 times each constitutes 1 sleep cycle.

– The final period of REM sleep may last a half hour to an hour.

GO TO BED

• If you are not sleeping and are deprived of REM sleep, tend to try and catch up from that REM time they missed.

• Seems to serve a psychological function for people and animals.

• Those who get REM sleep tend to learn faster and are “sharper”

Drugs and Consciousness

• Drugs have different effects on individuals. Some drugs can slow a person down while others can spur them into rapid action

• Addiction is when a person takes a drug long enough that the body then craves it to feel normal.

• Alcohol, nicotine, and other drugs are considered addictive.

Depressants

• Depressants are drags that slow the activity of the nervous system and generally give people a sense of relaxation and can have negative effects.

• Two types of depressants are– Alcohol– Narcotics

Alcohol

• Small doses can be relaxing to an individual and high doses can put someone to sleep. Too much can be lethal.

• Intoxication is another word for drunkenness and can poison the body and brain.

• Effects:– Slurring speech– Loss of Coordination– Judgment– Actin da fool

Narcotics

• Narcotics are addictive substances/depressants that have been used to relieve pain and induce sleep– Heroine, Morphine, Codeine

The use of this drug can impair judgment and consciousness as well as have lethal effects

Withdraws can lead to a deep drop into depression and cause chills, rapid heartbeat, insomnia, vomiting.

Stimulants

• Stimulants increase activity of the nervous system and can speed up heart/breathing rate.

• Nicotine– This stimulant can spur a release of the hormone

adrenaline which causes heart rate to increase and ,make people feel more alert and attentive.

– Decreases Appetite– People who quit may become nervous, drowsy,

headaches, etc.

Amphetamines

• This is another kind of stimulant that are known for helping people stay awake as well as reducing appetite

• First used by soldiers in WWII in order to stay awake during the night.

• If taken in high doses this “high” can last for days at a time.

• The “crash can be devastating and can lead a person into a deep depression and fatigue.

Amphetamines

• High Doses may also effect ones consciousness and can alter ones state of mind.

• Hallucination- is a perception of an object or a sound that seems real but it is not. (Bugs crawling on them)

• Delusion- a false idea that seems real. (Chased by someone)

Cocaine

• This drug can release feelings of pleasure, reduce hunger, deaden pain, and boosts self-confidence.

• Cocaine can cause muscle loss and lining of the nose and heart to deteriorate

• Crack is a more powerful and chemically impure form of the drug that can cause more problems based on its impurity

Hallucinogen

• Hallucinogen is a drug that produces hallucinations as well as feelings of relaxation and pleasure.

• Marijuana – Impairs perception and coordination making it

difficult to operate machinery – Increases heart rate – May become confused or lose sense of self.

LSD

• Also known as acid and can produce intense hallucinations

• “Open New Worlds”

• Intense negative symptoms that can lead to tragic results

• “Flashbacks”

4 Types of Treatment

• 1. Detoxification

• 2. Maintenance Programs

• 3. Counsling

• 4. Support Groups