Habituation & Sensitization I

Massed presentation

"Everything happens at once." Ex. Elephant shown to baby twenty times in succession, three seconds apart. Ex. Cramming for a test → worse performance with time delay.

Spaced presentation

"Everything is spaced out." Ex. Elephant shown to baby twenty times in blocks of five, with twenty-minutes in-between blocks. Ex. Studying for a test over two weeks.

What 3 factors influence habituation?

1. Novelty of the stimulus 2. Frequency of presentation 3. Time between exposures

Habituation

A decreased response to a frequent but innocuous stimulus.

What does spontaneous recovery indicate?

A lack of retention. Hence, spaced presentation has less spontaneous recovery (more likely to remember learned response).

Dishabituation

A renewal of a response, previously habituated, that occurs when the organism is presented with a novel stimulus.

Spontaneous recovery

A stimulus-evoked response that has been weakened by habituation increases in strength or reappears after a period of no stimulus presentation. When you "lose memory" for the habituated association.

Dual-Process Theory

A theory that explains both habituation and sensitization as aspects of the same system with two different parts.

Opponent-Process Theory

A theory that proposes there are two systems, one focused on positive experiences and one on negative ones. The brain makes comparisons between the two systems constantly (unlike the Dual Process, where there is an overall valence factor) Would say that habituation occurs faster to the FIRST component you experienced (e.g., negative feeling on a roller coaster).

What kind of organisms habituate and sensitize?

All living things → even single-celled organisms.

Sensitization

An increase in behavioral response over time.

How can researchers measure the strength of habituation?

By introducing a time delay a. Measure that habituation has taken place by showing a reduction in response. b. Introduce time delay c. Is the habituation still there or not? Time delay should be longer than a few minutes (that only displays short-term habituation).

How do researchers measure the strength of habituation?

By introducing a time delay.

How does a researcher confirm that habituation is specific to a particular sensory stimulus?

Change what is happening + record what happens. Ex. Present baby with different stuffed animal → if the infant is fatigued, the response will not change.

Acquisition

Displaying a habituated or "learned" response

What is the difference between spontaneous recovery and dishabituation?

Focus on the length of the delay: Dishabituation: a. Not a long time delay b. Something else is shown in-between Spontaneous recovery: a. Time delay present b. No other stimulus in-between

Sensitization is more likely to _____________ to other things.

Generalize Can occur for a stimulus that has been habituated.

Massed presentation and habituation

Habituation develops quickly. "Okay, I get it." However, once acquired, the habituation will not last long.

Spaced presentation and habituation

Habituation develops slowly. However, once acquired, the habituation will last longer (you are more used to the stimulus coming back with the large passage of time).

How does habituation relate to Aristotle's associationism?

Habituation is a form of associative learning → you are associating a stimulus with a threat, or not a threat.

Short term habituation

Habituation that goes away in seconds or minutes.

Long term habituation

Habituation that lasts longer.

The more ________________ the stimuli, the more likely an organism is to sensitize.

Intense

How fast does learning occur during the presentations?

Learning occurs quickly on early presentations, then levels off.

What process makes the information "learned" during habituation stay in our memory?

Long Term Potentiation (LTP) More neural firing at first time of exposure, less neural firing on second exposure.

Valence-focused

Meaning emotionally positive or emotionally negative.

What type of stimuli is associated with sensitization?

Noxious stimuli (e.g., confusing a raisin for a cockroach, spouse leaving dishes in the sink)

According to DPT, sensitization is due to a ____________________.

Pathway that has a high-threshold (not activated easily), but when activated it causes great activity.

According to the DPT, habituation is due to a ____________________.

Pathway that is weakened with repetition.

Retention

Retaining a habituated response after a time delay.

Why is the Coolidge Effect not a valid argument?

Sensitization can occur with strong positive stimuli. "If husband really loves wife, he should sensitize to her."

Short term sensitization

Sensitization that lasts for a short amount of time.

Long term sensitization

Sensitization that lasts longer.

How could a research demonstrate that sensitization occured?

Show that a minimal stimulus presence results in a larger response compared to baseline (how organism responded to the stimulus the first time they encountered it).

Sensitization in complex organisms (humans)

Stimuli that is "negative" to us is more complex → e.g., a song you hate, a roommate being messy, etc.

What does dishabituation prove?

That the reduction in an initial response WAS habituation, not fatigue.

Stimulus specificity

The idea that you are only able to habituate to one stimulus.

Novelty of stimulus

The less novel a stimulus is, the more likely you are to habituate to it. The more novel a stimulus is, the more likely you are NOT going to habituate to it.

Frequency of presentation

The more often you experience a stimulus, the more likely you are to habituate to it.

Time between exposures

The more time between the exposures to the stimulus, the less likely you are to habituate to it. The less time between the exposures to the stimulus, the more likely you are to habituate to it. Example: Baby sees elephant every two minutes: more likely to habituate. Baby sees elephant every two weeks: less likely to habituate.

How is habituation quantified?

When a particular response to a particular stimuli is measured → Asymptote formed. Ex. "Mean amplitude of acoustic startle response."

Generalization

When an individual responds to a new stimulus in a similar way to another stimulus because they see it as part of the same category.

Example of long-term habituation

When there is elapsed time after the stimulus is presented and habituation is still present.

When does habituation occur?

When we lose awareness of something we often experience. Ex. Projector in classroom

How would the Opponent-Process Theory explain boredom on a roller coaster ride?

You habituated to the negative part of the roller coaster (falling down) - going down is not scary anymore. You experienced the positive part (coming back up), but it is not as exciting. Think: roller coasters have larger hills → more negative intensity is needed to experience enjoyment.

What is an example of dishabituation?

a. Baby looks at monkey → responsive b. Baby looks at mokey again → less responsive c. Baby looks at rhino → responsive d. Baby looks at monkey again → responsive (like before)

How can a researcher "test" for habituation?

a. Present a stimulus + measure response b. Take stimulus away + measure response c. Present stimulus again + measure response

Example of spontaneous recovery

a. Researchers introduce a significant time delay b. Day or so passes c. Stimulus presented again d. Heightened response exhibited

Habituation pathway

a. Stimulus activates sensory neurons b. Brain is "startled" c. Motor neurons receive signal from brain d. Response (R) The activation of this pathway → decreased activation

What are the main takeaways of the Dual Process Theory?

a. Strong, noxious stimuli will activate both the habituation and sensitization systems → will get increase in responsiveness. b. Moderate stimuli can activate both, but with a minimal state level habituation may drive activity.

Example of short-term habituation

a. The rat will eventually not respond to the sound → will devote cognitive energy towards other things. b. BUT, the rat will display a heightened response when that same sound is played days later.

The state system

a. Threshold passed (e.g., rat hears loud noise) b. State system activated c. Red bubble → state system "yelling" at the remaining pathway to increase activation!

Massed presentation has greater _________________ and less______________.

acquisition; spontaneous recovery.

Spaced presentation has slower ___________________ and less ________________.

acquisition; spontaneous recovery.