is brain-behavior behavior? zif so, it can be conditioned just like other behaviors

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Is brain-behavior behavior?

If so, it can be conditioned just like other behaviors

Definition of Learning

Learning is an adaptive1 permanent change2 in behavior or behavior potential3 that is produced as a result of prior experience4

1 occasionally maladaptive such as depressed mental set, obsessions

2 not due to fatigue, injury 3 includes tendencies to respond that might not have been

tested 4 excludes maturation, disease, instinct

Two forms of conditioning

Classical conditioning Hard-wired linkage between stimulus and response

(e.g., food and saliva) Anything acting as signal of food can produce response

Operant conditioning Training linkage between stimulus and response

through reinforcement behavior strengthened if followed by reinforcement behavior weakened if followed by punishment

Law of Effect (Thorndike)• Rewarded behavior is repeated

Components of conditioning

Acquisition initial stage of

learning, during which a response is established and gradually strengthened

Effective pairing of reinforcement

Extinction

diminishing a conditioned response occurs when an response is not followed by a

reward

Extinction and spontaneous recovery

Strengthof CR

Pause

Acquisition(response+ reward)

Extinction(no reward)

Extinction(no reward)

Spontaneousrecovery ofresponse

Weak

Strong

Time

Operant Conditioning

Spontaneous recovery reappearance, after a rest period, of an

extinguished conditioned response

Generalization tendency for stimuli similar to the conditioned

stimulus to evoke similar responsesDiscrimination

Identify specific stimulus from set of similar stimuli to evoke similar reinforced responses

Operant Conditioning

B.F. Skinner (1904-1990) Built on

Thorndike’s Law of Effect

Discovered schedules of reinforcement

Operant Conditioning

Operant Chamber (“Skinner Box”) chamber with a

bar that an animal can press to obtain a food reinforcer

Frequency of responses are recorded

Operant Conditioning

Reinforcer any event that follows a behavior

AND strengthens the behaviorShaping

procedure in which reinforcers guide behavior toward a desired goal

Principles of Reinforcement

Primary Reinforcer an innate reinforcer satisfies a biological need

Secondary Reinforcer a conditioned reinforcer an event that gains its reinforcing

power through its association with a primary reinforcer

Schedules of ReinforcementContinuous Reinforcement

reinforce desired response every occurrencelearning occurs rapidlyextinction occurs rapidly

Partial Reinforcement Reinforce response only part of the time

learning occurs slowlyBut connection resists extinction

Extinction curves due to continuous and partial reinforcement

ADHD and responding to partial reinforcement

Different Partial Reinforcement schedules

Variable Interval

Number of responses

1000

750

500

250

010 20 30 40 50 60 70

Time (minutes)

Fixed Ratio

Variable Ratio

Fixed Interval

Steady responding

Rapid respondingnear time forreinforcement

80

Schedules of Reinforcement Fixed Ratio (FR)

behavior is reinforced only after behavior occurs a specified number of times (e.g., 1 in 3)

the faster you respond, the more rewards you get!

different ratios very high rate of responding like piecework pay

Variable Ratio (VR) behavior is reinforced ON

AVERAGE after behavior occurs a specified number of times (e.g., 1 in 3 on average)

like gambling, fishing very hard to extinguish

because of unpredictability

Fixed Interval (FI) behavior is reinforced only

after a specified time has elapsed

frequency of behavior increases when the time for reward draws near

Variable Interval (VI) behavior is reinforced at

unpredictable time intervals

produces slow, steady responding

like pop quiz!

Reinforcement Schedule examples

Buying a lottery ticket and winning VRWatching & seeing a shooting star VIReceiving allowance Saturday for

having clean room FIHotel maid gets 15-min break after

cleaning four rooms FR

Shaping

Can leave lab once rat touches lever three times in 10 seconds

Shaping

Successive approximations to goal behavior

Punishment

An aversive event that decreases the behavior that it follows

Operant Conditioning

Appetitive AversivePresented Positive

reinforcementPositive event followsresponse e.g. reward

PunishmentDiscomfort followsresponse e.g.punishment

Removed PunishmentPositive stateremoved afterresponse e.g. time-outor omission training

NegativereinforcementDiscomfort removedafter response e.g.escape or avoidancelearning

Problems with Punishment

Punished behavior is not forgotten, it's suppressed--behavior returns when punishment is no longer present

Causes increased aggression- shows that aggression is a way to cope with problems

Creates fear that can generalize to undesirable behaviors, e.g., fear of school

Does not necessarily guide toward desired behavior--reinforcement tells you what to do, punishment only tells you what not to do

Punishment teaches how to avoid it

Biofeedback

When one becomes aware of:

BreathingHand or foot temperatureHeart rateMuscle Tension

- You can change it. This is the essence of biofeedback.

When you become aware of your own brain activity –you can change it also.

Feedback Screen

Therapist Monitor

EEG Sensors

Therapist and client/game screen

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