MBB 1

Cognition

Cognition encompasses the activities (smth you do) of “the mind” (mental rep.)

• Involves the acquisition and use of knowledge (informed by sensing and ‘feeling”).

Mental processes that cognition includes

perception, attention, memory, decision-making, reasoning, problem-solving, imagining, planning and executing actions

The Perceptual-Cognitive Cycle

In any given moment, our current experience is a product of integrating the perceptual present and the cognitive past...

• Anactive,embodied,emotionalagent embedded in the physical and socio-cultural world

Talk through The Perceptual-Cognitive Cycle

Cognitive agent

“mentally represent” their world

eg. A cognitive agent can represent to itself a goal like obtaining an object from a location that is not in its immediate environment.

• eg. Ollie salivates to the sound of his treats being opened.....

Measuring the mind

Learning

Learning is the set of biological, cognitive and social processes through which organisms make meaning from their experiences, producing long-lasting changes in their behaviour, abilities, and knowledge.

• Learning helps us to recognise important things from past experiences and predict the future. (IMPORTANT)

Foundations of learning

Two fundamental forms of non-associative learning are shared by all species: sensitisation and habituation

Sensitisation

A temporary state of heightened attention and responsivity that accompanies sudden and surprising events. The learner remains alert to potentially threatening stimuli and has an increased response to subsequent stimuli.

Habituation

The gradual diminishing of attention and responsivity that occurs when a stimulus persists without being associated with threatening or rewarding consequences (i.e., it is safe to ignore and to fade into the background noise).

Significance of associations in conditioning

It is important to learn associations between stimuli that reliably predict biologically significant events, and to learn to respond adaptively.

Biologically significant stimuli that relate to survival

• Stimuli that naturally cause either defensive (fight, flight, freeze) or appetitive (approach) reflex responses.

• Stimuli that are inherently punishing (aversive) or rewarding (appetitive)

• The effects of such stimuli on our physiology is not learned

• called UCS in classical conditioning: naturally produces autonomic (invol.) response

Conditioning as associative learning

learning associations (relationships) between stimuli, and/or between stimuli and behavioural responses.

Classical conditioning

Learning a predictive relationship between an originally neutral event and a biologically significant event that itself naturally causes an autonomic reflex response, so that the previously neutral event becomes a meaningful stimulus that can then produce the autonomic reflex response on its own

Classical conditioning with key words

Learning a predictive relationship between a neutral stimulus and an unconditioned stimulus and its unconditioned response, so that the neutral stimulus becomes a conditioned stimulus that can cause a conditioned response on its own.

Before conditioning

1. The neutrality of stimuli that have not yet been associated with appetitive or aversive stimuli.

2. The innate reflex responses of the learner that occurs to stimuli that are naturally rewarding (appetitive) or punishing (aversive or threatening)

During conditioning

Experiencing a predictive relationship (association) between a neutral stimulus and a biologically relevant stimulus.

After conditioning

The previously neutral stimulus can now produce a learned reflex response in preparation for (or expectancy of) a biologically relevant stimulus.

Pavlov Eg

Before:

NS - bell

UCS - food

UCR - salivation

During:

Bell is repeatedly presented immediately before the food which evokes salivation (UCR). Then again after delay (eg. day, week etc)

After:

CS, the bell, evokes the CR, salivation, on its own in absence of UCS

Classical conditioning has occurred when:

The reflex salivation response occurs when presented on its own in response to the formerly neutral stimulus

CCR acquisition

Stimulus generation

classically conditioned response would generalise (transfer) to other similar stimuli

• eg. all bell sounds

• occurs naturally

Stimulus discrimination

• must be trained to only exhibit CR to specific CS

Extinction

Extinguish the classically conditioned response by presenting CS without UCS repeatedly over time

Spontaneous recovery

• If you rest Ollie after a series of extinction trials and then present the bell again, the conditioned response will return.

• Extinction spaced over multiple sessions will gradually prevent spontaneous recovery (at least in contexts similar to the extinction context).

Rapid reacquisition

Ollie would re-learn the conditioned salivation response more quickly than he did the first time.

Watson’s belief

Behaviourism: believing that environmental conditions are everything

Little Albert Watson & Raynor

Alfred was not afraid of stimuli but showed startle response + distress to metal bar strike sound

• UCS-UCR was the sound and fear response

• Albertwasexposedtotwoinstancesoftherat followed by the loud sound in an initial session, and another five instances a week later.

  • Thiswassufficienttoproduceanextreme conditioned fear response to the white rat alone

  • Generalisation also occurred to other furry animals, and Santa’s white beard.

  • They did not get a chance to extinguish the response.

Operant conditioning

Behaviour is shaped by the learner’s history of experiencing rewards and punishments for their actions.

• According to Skinner – our behaviours are shaped by our history of experiencing rewards and punishments as consequences.

The Skinner Box

Pressing the lever was the target behaviour, which could be

strengthened through reinforcement and weakened through punishment.

• a controlled environment in which to study the behavior and learning of laboratory animals

• For example, the rat might receive a food pellet each time it presses the lever. In this case, we would say that the lever-pressing has been positively reinforced by receiving a rewarding consequence.

Reinforcement

A behaviour is reinforced (strengthened) whenever a desirable outcome is the consequence.

• Behaviours that are reinforced are more likely to be repeated.

• A reinforcer is any consequence of a behaviour that makes that behaviour more likely to recur in future.

• Reinforcers can be either positive (+) or negative (-).

Positive reinforcement

An animal will learn to reproduce a behaviour if the consequence is receiving something pleasant.

• Positive reinforcer is something pleasant that is added to increase behaviour

Negative reinforcement

An animal will learn to reproduce a behavior if the consequence is that something unpleasant will stop.

• Negative reinforcer something unpleasant that is removed to increase behaviour

Continuous reinforcement vs partial

• Continuous reinforcement rarely occurs in natural environments

• Behaviour is usually reinforced on a partial “schedule”.

Partial reinforcement

Partial reinforcement leads to more persistent learning because the learner becomes accustomed to reinforcement occurring on some occasions and not others.

Continuous reinforcement

Continuous reinforcement leads to rapid extinction once the reinforcer is withheld.

Extinction of reinforced behaviour

• Extinction of an operantly conditioned behaviour occurs when reinforcement is withheld.

• Not immediate - sometimes there is a brief increase in responding referred to as an extinction burst followed by decrease in trained behaviour.

• The figure shows that responses that have been reinforced on a partial schedule will be slower to extinguish than those reinforced continuously

Shaping

Shaping reinforces successive approximations to the desired behaviour (reinforcing small steps).

• Start by reinforcing a high frequency component of the desired response.

• Then drop this reinforcement – behaviour becomes more variable again.

• Await a response that is still closer to the desired response – then reintroduce the reinforcer.

• Keep cycling through as closer and closer approximations to the desired behaviour are achieved.

• Enables the moulding of a response that is not normally part of an animal’s repertoire.

• for more complex behaviours

Punishment

• A behaviour is punished (weakened) whenever the learner experiences an undesirable consequence for that behaviour.

• Behaviours that are followed by punishment are less likely to be repeated.

• A punisher is any consequence of a behaviour that makes that behaviour less likely to recur in future

• Punishers can also be either positive (+) or negative (-).

Positive punishment

An animal will stop producing a behaviour if the consequence is the presentation of an unpleasant stimulus.

• Positive punisher
  • An unpleasant stimulus that weakens behaviour when added as consequence of the behaviour

Negative punishment

An animal will stop producing a behaviour if the consequence is that something desirable is taken away.

• Negative punisher
• A pleasant stimulus that weakens behaviour when removed as a consequence of the behaviour

When is punishment effective

Contingency – the relationship between the behaviour and the punisher must be clear

Contiguity – the punisher must follow the behaviour swiftly (occur close tgt in time)

Consistency – the punisher needs to occur for every occurrence of the behaviour (not sustainable)

Drawbacks of punishment

• Positive punishment rarely works for long-term behaviour change.

• It tends to only suppress behaviour.

• It does not teach a more desirable behaviour.
  • Produces negative feelings in the learner, which do not promote new learning.
  • Harsh punishment may teach the learner to use such behaviour towards others (social learning).

If the threat of punishment is removed, the behaviour returns. Why?

Reinforcer drives behaviour so if punishment is partial , then partial reinforcement can occur and competes so behaviour is maintained

• eg. crossing red light

More effective alternatives to punishment

• Stop reinforcing the problem behaviour (extinction).

• Reinforce an alternative behaviour that is both constructive and incompatible with the undesirable behaviour.

• Reinforce the non-occurrence of the undesirable behaviour.

• Generate your own examples for each of these.

Controlling and predicting ‘voluntary’ behaviour

Learners pay attention to the stimuli that predict when rewards and punishments will occur signal likelihood of rewards/ punishment

• They learn to recognise the antecedents’ (pre cursors or cues) to reward or punishment

• They learn that the rewarding or punishing outcome is contingent on (depends on) producing a particular behaviour.

• This can be leveraged to control when a learner will produce a behaviour.

• For example, if a green light reliably signals the availability of reward, there is no point pressing the lever if the green light has not been illuminated. (assoc. bw GL (antecendent) and lever (CC))

• The relationship between the green light and it’s associated reward is classically conditioned.

• The relationship between pressing the lever and receiving the food is operantly conditioned.

ABC model

“ABC model” of operant conditioning
• Antecedent →Behaviour →Consequence

Antecedent

a formerly neutral stimulus that becomes a conditioned stimulus through its association with the rewarding consequences.

Behaviour

operantly conditioned through the consequence

Discriminant stimuli

An antecedent becomes a discriminative stimulus when it signals which of two or more behaviours is appropriate in a particular context.

• eg. in a Skinner Box, a green light may signal food availability whereas a red light may signal foot-shock.

• Learning the relationship between the discriminant stimuli and the unconditioned stimuli is based on a classically conditioned CS-UCS association.

• Producing the correct behaviour in response to the correct stimulus context is operantly conditioned through reward (positive reinforcement), shaping and extinction of incorrect responses.