PSYC 361 MT2: AROUSAL & GOAL-DIRECTED BEHAVIOUR (2) Theories & Experimental Evidence

Question 1

Activation Theory of Motivation

Answer 1

Activation (Arousal) = part of emotion
- as physiological response that accompanies emotional experience
- as dimension of emotions (dimensional theory of emotion)

Arousal (like drive) hypothesized to energize behaviour
- Duffy: energy mobilization, emphasizing autonomic system arousal
- provided physiological account of drive (drive as “state”)—> diverges from drive theory

Question 2

Reticular Activation System in the Brain

Answer 2

**Reticular Formation* in midbrain
- receives all sensory inputs except olfactory (limbic)
- integrating & coordinating activities in CNS & PNS

Reticular Activating System (RAS)
- Ascending: cortical “preparation”
- Descending: motor/muscular tone-up

Highly neuromodulatory: DA, NE, 5-HT, HIS, acetylcholine, neuropeptides

Some brain stimulation & lesion studies support role for attention/consciousness/arousal

Pharmacological modulation of RAS activity also lends support

Question 3

Reticular Activating System in the Brain- EEG ACTIVITY

Answer 3

Correlates with arousal states
- Alpha wave: awake, relaxed
- Beta wave: awake, activated

Question 4

Optimal Arousal Level

Answer 4

Motivational POV: needs to be optimal level of arousal for behaviour

Inverted-U function of arousal; optimum stress = area of best performance

Question 5

The Yerkes-Dodson Law

Answer 5

Brightness discrimination tasks (BvsW) + levels of shock as punishment
- Easy task: large contrast, best performance with high level of shocks (high arousal)
- Medium task: intermediate contrast, best performance with medium level of shocks
- Hard task: minimal contrast, best performance with low level of shocks (low arousal)

Cognitively difficult/intellectually demanding tasks, may require lower level of arousal for optimal performance to facilitate concentration; tasks demanding stamina/persistence may be performed better with high levels of arousal, presumably to increase & maintain motivation for “boring” tasks

Question 6

Caffeine Increases Arousal & Affects Performance

Answer 6

Activates adenosine receptors (GPCRs) in NS

Anderson: gave undergrads different levels of caffeine & observed performance on easy & difficult language tasks
- found performance of easy task enhanced by higher levels of caffeine & higher caffeine levels impaired performance of difficult task

Support inverted-u function

Question 7

The Easterbrook Hypothesis

Answer 7

Hypothesized arousal levels alter attentional/perceptual processes & affect performance
- attention works like “spotlight”; increased arousal decreases range of attention
- relevant (R) & irrelevant (IR) cues coexist & are simultaneously processed

Performance modulated by arousal levels but also relative to task itself

Research into eyewitness reporting in criminology/forensics

Question 8

Evidence for the Easterbrook Hypothesis

Answer 8

(Anderson & Revelle): undergrads asked to proof-read articles while provided varying caffeine amounts
- 2 types of errors: intra-word (typo/misspell) & inter-word (wrong syntax/grammar)
- test sensitivity to different types of errors with different arousal levels

Aroused individuals = lower detection rate of inter-word errors, required wider range of cue utilization
- detection rate of intra-word errors unaffected by caffeine

Question 9

Drive Theory vs Activation Theory

Answer 9

Both theories attempt to address an intensity dimension of motivation but

Drive Theory: argues that it is optimal to maintain minimal level of drive, since deviation from homeostasis is smallest

Activation Theory: argues that it is optimal to maintain a somewhat intermediate level of arousal, since performance is more reliable at this optimal level & is affected at lower/higher arousal levels

Drive Reduction focuses on meetings biological need; however, arousal may not always be relevant to biological need

Suggests animals under certain circumstances will seek out stimulation to maintain such an optimal level of arousal

Question 10

Environmental Stimulation & Arousal

Answer 10

Lucid Behaviour: activates that we call “recreation, entertainment/idle curiosity—art, philosophy, pure science”; does not have biological function we can clearly recognize

Seeking the following quilting’s in stimuli:
1) Novelty: surprise, incongruity, unfulfilled expectations

2) Uncertainty: amount of info carried by stimulus, ambiguity

3) Conflict: multiple responses aroused at same time

4) Complexity: # of distinguishable elements, dissimilarity of elements

Environmental Load: high vs low; amount of qualities present in these environments

Individual Differences: screeners vs non-screeners

Question 11

Motivated Behaviour & Reinforcement by Arousal

Answer 11

Berlyne: hypothesized different arousal levels due different affects
- Positive affect aroused by stimuli that produce medium level of arousal

• Animals seek out medium arousal stimuli
• Stimuli too far above/below optimal level are aversive
• Motivated approach & avoidance behaviour to stimuli that do not restore homeostasis
• Positive affect also reinforces behaviour without having to restore homeostasis

Question 12

Aesthetics & Arousal

Answer 12

Smith & Dorfman: complexity of visual patterns leads to different dynamic changes in the liking upon repeated exposure (shifts in arousal levels of stimuli produced)

Vitz: aesthetic appreciation of different tone sequences changes with raters’ expertise

Humour & comedy have pleasant arousal-eliciting qualities—why we enjoy them

Question 13

Instrumental Behaviour & Neural Representations

Answer 13

Instrumental behaviour more sophisticated & flexible than SR learning would allow

Question 14

Goal-Directed Action involved Multiple Processes

Answer 14

Purpose of goal-directed behaviour is to achieve desired outcome through performing chosen behaviour, animals must be able to:

• form direct SR associations (instrumental conditioning through reinforcement)
• evaluate value of outcome as an instrumental goal (incentive motivation)
• evaluate hedonic value of outcome (dissociable from incentive motivation)
• decipher & encode action-outcome contingency
• process physiological & environmental cues

Question 15

2 Value-Processing Systems

Answer 15

Hedonic Value System: how much animal is willing to consume the reward
- Hedonic value can be changed by satiation/devaluation etc.
- Changes in hedonic value directly affect consumption of reward
- Reflects how much animal likes reward

Instrumental Incentive Value System: how much animal is willing to work for reward (ie. to what extent outcome of action is a desirable goal)
- Reflects how much animal wants reward
- Animals must learn through experience that a change in hedonic value of food changes its incentive value (ie. food is not worth working for when they are not hungry)

Question 16

Devaluation Changes Goal-Directed Action Performance

Answer 16

In Devaluation, defaulted group expected to associate sugar with illness, devaluing sugar

In Test 1, groups (1&2) not expecting sugar pressed lever equally frequently; Group 3 expecting sugar pressed lever less frequently

In Test 2, re-exposure to sugar led devalued groups (2&3) to press lever less frequently (ie. learned that sugar is not as nice & not worth working for)

Result suggests that during relearning, animals experienced discomfort associated with sugar & that this experience reduced incentive value of the outcome & hence, performance

Question 17

Habitual Responding NOT Affected by Devaluation

Answer 17

Holland: repeated instrumental conditioning reduces impact of devaluation (ie. animal will keep pressing lever for food reward even after it has been associated with illness)

• Devaluation still leads to decreased incentive value but performance unaffected
• Suggests no role for incentive learning
• Repeated instrumental conditioning procedure leads to strong SR connections
• Habit & goal-directed action operate differently

Question 18

2 Systems Also Present in Humans

Answer 18

Devaluation lesions studies in rodent models: instrumental conditioning involve 2 systems distinct neural substrates
- Incentive learning (goal-directed system): PFC + dorsomedial striatum
- SR learning (habits): dorsolateral striatum

Valentin: examined neural substrates of goal-directed component in humans
- Trained participants to acquire food reward with higher probability, then “devalued” reward by satiation
- Participants self-reported less pleasant less for devalued food (hedonic value change) & reduced choice for high-probability reward (incentive value change)
- fMRI found areas of the orbitofrontal cortex showed increase activity before devaluation & decreased activity after devaluation—suggests role for encoding incentive value

Question 19

Liking vs Wanting (Revisited)

Answer 19

2 dissociable constructs
- Stereotyped consumptive behaviour for liking
- Brain damage/manipulation to differentiate the 2
- Animals still “like/dislike” reward following damage to DAergic system, they are no longer motivated to earn reward— no longer goal-directed

Intracranial self-stimulation in rats (ICSS)
- Mesocorticolimbic DA system: VTA DA neurons projecting to frontal cortex & NAcc
- ICSS causes dramatic DA increases within NAcc— key site for reward-related learning & addiction
- DA agonists increase ICSS whereas DA antagonists suppress it
- Lesions of mesocorticolimbic DA system disrupt ICSS

Question 20

What Signals do DAergic Signalling Carry?

Answer 20

Electric recording from DA neurons (monkeys)
- before learning: DA neurons fire when reward (US) occurs
- US unsignalled, therefore unexpected at this point

Once CS-US association established, DA neurons now fire to CS, DA neurons do not fire to reward anymore

If expected award missed, DA neurons pause firing

Da neurons also ram up firing after CS presentation if US delivery is less certain— maximal “ramping” seen when p = 0.5 (maximal uncertainty)

Question 21

What Signals do DAergic Signalling Carry?

Answer 21

DA transmission comes in different timescales that mediate different functions of the brain
- Fast (subsec): DA transmission typically observed in VTA & substantia nigra— shows prediction-error responses to rewards
- Slow (sec-min) & Tonic (continuous): DA transmission modulates many other brain functions & appears to be unrelated to reward processing

Animals must understand their actions result in outcome (ie. detection of causal contingency between pressing lever & food delivered) & outcome is goal that is desired by animal

Fast DA transmission hypothesized to underly brain’s ability to decipher & encode action-outcome contingency

Question 22

The Prelimbic Cortex

Answer 22

In rats: known to receive DA input from VTA

The dorsolateral PFC in humans involved in planning, response selection, control of purposive actions— knowledge of action-outcome contingencies

Damage = reduced ability of animals to detect contingency changes
- rats failed to discriminate between actions & outcomes— if 1 reward presented non-contingently, reduced responding for both rewards
- generalized disruption in task performance = responses not truly goal-oriented

Question 23

Previous Learning can Affect Goal-Directed Action

Answer 23

Pavlovian CC’d stimuli can modulate instrumental performance

In conditioned reinforcement, rat 1st learns light predicts food, then test whether rat will work for light (indicator)

In PIT, rat learns separately light predicts food & lever press = food. Then rat presented with both l ever & light—> rat will press lever more in presence of light even if light has not been previously paired with lever pressing

Question 24

Goal-Directed Behaviour is Complex

Answer 24

Involves:
- form direct SR habits
- value of outcome as instrumental goal (incentive motivation)
- hedonic value of outcome (dissociable from incentive motivation)
- encode of the action-outcome contingency

Influenced by Pavlovian processing including conditioned reinforcement (CRf) & Pavlovian-to-Instrumental Transfer (PIT)

Question 25

Summary of Arousal & Goal-Directed Behaviour

Answer 25

Activation (arousal) can affect range of cognitive (physiological) processes that affect performance

Optimal level of arousal is a somewhat medium level of arousal but also task-dependent

Goal-direction behaviour is complex & involves multiple processes

DA transmission in different brain areas mediate goal-directed learning