PSYCH EXAM 2

Essential apraxia

Inability to perform motor tasks due to frontal lesions.

Agnosia

Inability to recognize objects due to back lesions of language.

Expressive aphasia

Inability to produce speech due to damage in Broca's area.

Broca's Area

Frontal association area responsible for speech production.

Controls motor projection areas for speech: throat, tongue, jaw, lips

Corpus Callosum Severance

Surgical procedure to reduce seizures by severing communication between the left and right hemispheres.

Outcome of Corpus Callosum Severance

leaves patients mostly normal but creates subtle independence between left and right brain

Contralateral organization

The left visual field is processed by the right hemisphere and vice versa.

This is the experiment: Patient looks straight ahead and a picture is flashed faster than the eye can move. they are asked, “What did you see?”

what is the result?

• Cup on right → Left hemisphere says “cup”

• Spoon on left → Left hemisphere says nothing

• When told to reach for the object with the left hand, the right hemisphere grabs the spoon

• If asked what it is, the left hemisphere guesses (e.g., "pencil"), and the right hemisphere may frown

if I am a split-brain patient and I have something shown in my right visual field, will I be able to vocalize what I saw?

yes

If I am a split-brain patient and I have something shown in my left visual field, will I be able to vocalize what I saw?

no

If I am a split-brain patient and I am shown something in my left visual field, will I be able to correctly choose the object with my left hand?

yes

Classical Conditioning

involuntary learning process where an organism learns to associate a stimulus with a response, resulting in a conditioned reflex. It involves pairing a neutral stimulus with an unconditioned stimulus.

Higher-Order Conditioning

A form of conditioning where a CS is paired with a new CS, causing the new CS to elicit a response.

Unconditioned Stimulus (US)

Stimulus that naturally elicits a response (e.g., food). input to reflex

no training

Unconditioned Response (UR)

Natural response to an unconditioned stimulus (e.g., salivation due to food). output to reflex

Conditioned Stimulus (CS)

Initially neutral stimulus that, after conditioning, elicits a response (e.g., bell).

Conditioned Response (CR)

Learned response to a conditioned stimulus (e.g., salivation in response to a bell).

Pavlov’s Finding doing Classical Conditioning

• Psychic Reflex: Dog perceives something and responds

• Conditioned Reflex: A learned reflex (CS before US)

Measures of conditioned response

Amplitude, Probability, and Latency

Amplitude

the strength of the conditioned response (can see how much saliva is produced in the tube)

Probability

How often the conditioned response occurs (eye blinks due to a bell) (3/10? 5/10?)

Latency:

time for CR to occur (how long till heartbeat is beating fast due to bell tone)

Acquisition Phase

Phase during which a conditioned response is established.

• Strength of CR increases with reinforced trials (CS + US)

• Growth rate flattens out when max response is reached (e.g., dog does not have infinite saliva)

Extinction

Decline of a conditioned response when a conditioned stimulus is presented without the unconditioned stimulus.

due to a buildup of inhibition

Acquisition _______ CR and Extinction _______ CR

Strengthens, Weakens

Spontaneous Recovery

• After a rest interval (e.g., 24 hours), CR reappears at almost previous strength but weakens faster

• Due to dissipation of inhibition

• extinction happens faster

Excitatory Association

Learning that arises from direct reinforcement.

Inhibitory Association

Learning that arises from the absence of reinforcement.

Contiguity

The principle that closeness in time is necessary for conditioning.

time in between presenting the CS (bell) and the US (food)

Optimal time interval:

best time (right time) between presenting the CS and the US to get the strongest CR

Could be different depending on the conditioning situation

Stronger CS

Stronger CR (louder tone, brighter light= more salivation)

ex: louder bell CS creates more salivation CR

Higher Order Condition (Second-order conditioning) steps

1. Establish CS → (e.g., Bell → Salivation)

2. Pair a new CS with the old CS, without the US → (e.g., Tone → Bell → Salivation)

3. Eventually, the new CS produces CR without US → (e.g., Tone → Salivation)

• US acts as a reinforcer for the conditioned reflex

• In higher-order conditioning, a CS acts like a US (secondary reinforcer)

• Classical conditioning is more versatile – It can happen even in the absence of an unconditioned stimulus

can opener —> food—→salivate

can opener—>salivate

squeaky door (replaces can opener)—→ can opener (replaces food)—→ salivate

squeaky door—> salivate

can’t continue this to the 4th, 5th, 6th due to extinction

Extinction:

Presenting a CS without a US leads to a decline in CR

Generalization:

• Similar stimuli produce similar responses (e.g., petting both dogs and cats)

• Example: A different pitch tone still produces salivation

child doesn’t understand concept between different animals pets both the cat and dog since they are similar

Discrimination

• Learning to differentiate between stimuli

• Example: Training “CS+” (high tone with US) and “CS-” (low tone without US) → CR only to CS

if you over train high pitch to food weak conditioned response to low tone

or you could do low pitch no food

have a weak conditioned response to one thing and a strong conditioned response to the other

Trial-and-error learning

Learning process where various actions are tried and the satisfactory ones are reinforced.

CS (tone) allows for preparation of the US (shock)

rabbit recieved a shock (US) with a tone (CS)

the heart rate now increases (UR)

do tone shock tone shock

heart rate decreased preparing for the shock after the tone

the tone CS informs the body to prepare for the shock US so the cS actually makes the heart rate CR decrease (compensation)

Law of Effect

• Behavior is strengthened when followed by reinforcement (“satisfying state of affairs”)

• Behavior is weakened when followed by punishment (“annoying state of affairs”)

Thorndike’s Puzzle Box (Cat Experiment)

A learning experiment conducted by Edward Thorndike where cats were placed in a box that could only be opened by performing certain actions. Successful escape behaviors were reinforced, leading to faster problem-solving in subsequent trials.

learning is incremental bit by bit

Operant conditioning

Operant Conditioning

1. Reinforcement: cat has to push paddle to get out of box

2. Behavior: learned push paddle to escape box

3. Mechanism: Law of Effect consequence of response

4. Delay: of reinforcement weakens response need reinforcement right away

Emitted Response

Behavior that is produced spontaneously (Operant Conditioning).

Elicited Response

Behavior that is controlled by a stimulus (Classical Conditioning).

Contingency Vs. Contiguity

• Contingency: Dependency between behavior and reinforcement

• Contiguity: Closeness in time makes learning happen

Positive Reinforcement

Adding a pleasant stimulus to increase a behavior. (food, approval)

Negative Reinforcement

Removing an aversive stimulus to increase a behavior. (Shock, alarms)

Positive Punishment

Adding an unpleasant stimulus to decrease a behavior. (shock when a response is made)

Negative Punishment

Removing a pleasant stimulus to decrease a behavior. (taking a way a toy from a child)

Discriminative Stimulus

Stimulus that signals under which conditions reinforcement will occur.

Discriminative stimulus example

• • Example: A rat presses a bar but only gets food when a light is on → eventually, it only presses when the light is on.

  • The stimulus does not cause the response or reinforcement; it sets the occasion for the response.

Operant Conditioning Parallels to Classical Conditioning

• Instead of a conditioned response (CR) → operant response

• Instead of an unconditioned stimulus (US) → reinforcement

• Instead of a conditioned stimulus (CS) → discriminative stimulus

Order difference between Classical Conditioning and Operant Conditioning

• Classical Conditioning: Stimulus (CS) → Reinforcement (US) → Response (CR)

• Operant Conditioning: Stimulus → Response → Reinforcement

Conditioned Reinforcers

Stimuli that gain reinforcing properties through association with primary reinforcers.

ex: a clicker for training dogs—> initially paired with food—> eventually reinforces behavior on its own.

Continuous Reinforcement

Reinforcement is given after every response. Does not lead to the strongest response in OC partial reinforcement better and stronger learning.

Partial Reinforcement Effect

• Reinforcing only some responses produces stronger responding than reinforcing all responses.

Interval

reinforce a response after a period of time

Fixed Interval Schedule

Reinforcement given after a fixed time period. (e.g., checking mail at a set time each day).

Lundquist exams are a fixed interval because the exam time is predictable even though the weeks in between vary

Variable Interval Schedule

Reinforcement given after varying time periods. e.g., checking email, which is delivered at random times).

NOT Predictable

straight slope because continuously pressing the bar not sure when reinforcement will happen

Predictability

affects behavior—fixed intervals lead to responses closer to expected reinforcement time.

Fixed Ratio Schedule

Reinforcement after a set number of responses. (e.g., factory workers paid per item produced). rat this many times to press the bar

Variable Ratio Schedule

Reinforcement after an average number of responses. (e.g., gambling, where payouts are unpredictable).

rat presses the bar continuously because it doesn’t know how many times to hit the bar. Straight slope

Shaping - Operant Conditioning

• Reinforcing successive approximations of a behavior to gradually guide toward a desired response.

Example: Training an animal to press a lever by reinforcing behaviors that get closer to the goal.

Example of Shaping

Bar is on the right rat is facing left

• as the rat continues to face the right direction of the bar it gets reinforced

• then as the at gets closer to the right side of the cage where the bar is, it get’s reinforced

• then as it gets closer and closer to the bar it gets reinforced

• now as the rat presses the bar it gets reinforced and now it only get reinforced for pressing the bar

Chaining Operant Conditioning

• Linking multiple responses into a sequence to train complex behaviors.

  • Example: Teaching a dog to fetch by reinforcing picking up the toy, bringing it back, and dropping it in order.

  • teach step 1 then teach step 1 and step 2 then step 1, 2 and 3 etc.

Conditioned Reflex

A learned response that occurs when a conditioned stimulus is presented before the unconditioned stimulus.

Delay of Reinforcement Issue

Delay can weaken the response in operant conditioning.

Edward Thorndike

Psychologist known for developing the Law of Effect.

Operant Conditioning

Learning where behavior is influenced by its consequences.

Rabbit Conditioned to Fear

An example of conditioned response to a negative stimulus, like a tone associated with an electric shock.

Key Takeaways from Learning Theories

Both classical and operant conditioning involve reinforcement but differ in response and stimulus relationships.

Reflexive Responses vs Learned Responses

Reflexive are automatic; learned are acquired through experience.

______, not contiguity is what matters in classical conditioning

Contingency

Contingency (dependency):

likelihood of US depends on CS’s presence or absence

the likelihood of getting shocked *US) depends on if the tone (CS) is playing or not playing

• Probability of US in the presence of CS relative to the probability of US in the absence of CS

Robert Rescorla Experiment:

Contingency matters more than contiguity (but contiguity still matters)

○ There are 3 groups of rats:

■ When the tone is on: 40% of the time group 1, group 2 and, group 3 are getting

shocked (US) exactly the same amount of time (shock is on 48% OUT OF 120

SEC)

■ When the tone is off:

● Group 1: get shocked 40% of the time

○ No fear conditioning= no fear of the tone

● Group 2: get shocked 20% of the time

○ Some fear response

● Group 3: get shocked 10% of the time

○ As a result of group 3 only getting shocked 10% of the time when

the tone is off→ group 3 associates the tone with MORE shocks

therefore the rats are more fearful of the tone→ their conditioned

fear response (CR) is stronger out of all 3 groups

■ The US (the shock) is contingent on the CS (the tone)

Belongingness:

biological preparedness to make certain associations

A CS and a US could belong together: two stimuli work better together- the opposite of equipotentiality

Pavlov’s two assumption

all associations are arbitrary contiguity causes conditions

1. any association in conditioning is arbitrary

2. Main important variable is contiguity or closeness in time of the CS and US

Equipotentiality

all stimulus has an equal potential to live together

Garcia and Koelling’s Experiment

4 groups of rats

■ 2 different CS and 2 different US: Do some CS’s and US’s work

better together?

○ Group 1: Gets light/tone (CS) with shock(US)

■ They DID avoid the water with light/tone

○ Group 2: Gets light/tone (CS) with illness (US)

■ They DID NOT avoid the water with light/tone

○ Groups 3:Gets Saccharin taste (CS) with shock( US)

■ They DID NOT avoid the water with saccharin taste

○ Group 4: Gets Saccharin taste (CS) with illness (US)

■ They DID avoid the water with saccharin taste

Garcia Effect: Taste Aversion

special facility for learning taste aversion ( taste-illness association) is difficult for classical conditioning because association established in one trial up to 24hrs between cs and US.

What does the rat infestation airport scenario teach about taste aversion and biological preparedness?

Rats avoided poisoned food after one trial due to taste-illness association (not typical classical conditioning). CS = taste; US = illness. They avoided taste with illness, but not taste with shock. Birds avoided visually distinct water (color) but not sour taste, showing rats rely on taste/smell while birds rely on vision—evidence of biological preparedness in learning based on species’ natural senses.

So where pavlovs assumptions right?

NO: there is not an arbitrariness; associations are selective and Contiguity is not everything because there were very long CS-US intervals and they still avoided toxic cheese.

Stages of Memory

• Two main stages:

  • Short-Term Memory (STM) – preferred term: Working Memory

  • Long-Term Memory (LTM)

Duration of Stages

• STM: seconds to minutes

• LTM: relatively permanent
  If a memory lasts longer than ~1 minute, it's already in LTM territory

Storage Capacity of Stages

• STM: limited to 7 ± 2 “chunks” (organized packets of info)

• LTM: potentially infinite

Processes in Memory

1. Encoding – getting information into the brain (see, feel, think)

2. Storage – maintaining the information

3. Retrieval – accessing the stored information

Working Memory (STM)

• Limited capacity (~7 items)

• Chunking helps organize info using prior knowledge from LTM

• Rehearsal:

  • Maintenance rehearsal: keeps info in STM

  • Elaborative rehearsal: links new info to existing knowledge, moves it to LTM
    "Weaving it into the fabric of what you already know"

Long-Term Memory (LTM)

• Has seemingly infinite capacity

• Retrieval can feel like searching for something that's still there

• Errors often semantic (e.g., confusing boat with ship)

Evidence for Stage Theory: Serial Position Effect

• Free recall task: read 20 words, recall in any order

• Primacy effect: better recall for early items (LTM)

• Recency effect: better recall for latest items (STM)

• U-shaped curve on a recall graph

Manipulations to the primary and recency effects

• Reduce recency: delay recall (e.g., 30-second distractor task)

• Reduce primacy: speed up word presentation

Pyschological code for short term and long term memory

Feature	Short-Term Memory (STM)	Long-Term Memory (LTM)
Duration	Seconds to minutes	Potentially permanent
Capacity	7 ± 2 chunks	Infinite (assumed)
Psychological Code	Phonological (sound-based)	Semantic (meaning-based)
Example Error	Confuse boat with coat	Confuse boat with ship

Childhood Amnesia

• No memories before age ~2

• Causes:

  • Underdeveloped hippocampus (memory formation)

  • Lack of language skills

  • No memory strategies

  • Infant experiences often lack relevance to memory systems

Flow of Information in Memory

→ First you receive information / a stimulus

➔ Then it goes into your short term memory

➔ Then if you rehearse this information

➔ This information that is rehearsed will go into your long

term memory

Two Kinds of Rehearsal:

Maintenance: hold the information in the short term

memory

Elaborative: move the information into the long

term memory