TJ&DM Flashcards
‘Gastrophysics’ borrowed its name from…
Psychophysics - the field that investigates the relationship between objective qualities of stimuli and experienced sensory qualities
Preconceived perceptions (gastrophysics)
Pre-conceived perceptions can enhance the experience of food, but it can backfire if it doesn’t meet expectations
Taste (gastrophysics)
○ Basic tastes come from the tongue: sweet, sour, salty, bitter (maybe umami = delicious?)
○ What about fruity, smoky, herbal, burnt, and all the many others?
○ These are flavours, and they emerge when smell is added
○ The classical tongue mapping is probably not true - there are relative differences, but great variability between people
Oral referral
Smell adds to the taste experience, but we do not realise this but “project” the experience to the tongue
- orthonasal
- retronasal
Orthonasal
Sniffing external aromas
Retronasal
Aromatic odour is received through the back of the mouth into the back of the nose during food consumption
- this is where the rich perception of aroma comes from
Key Gastrophysics message
® There are still individual differences and some people will prefer black and some will prefer white
® But when there appears to be a generalised trend that replicates, it can be useful in the real world
Is the science of gastrophysics sound?
Pay attention to the methods and statistics:
§ What kind of statistical tests are used, and are they appropriate?
§ How many tests are conducted, and do the authors control for multiple comparisons?
§ How many participants were tested, and what is the reported effect size (if any is reported)?
§ Do the results replicate across studies?
What other factors could have biased participants (and the results)?
Making decisions after consuming (Bode)
® Idea that if you are waiting for a large reward you will be impatient and think it is 2 secs quicker
Actually found that after a large reward, the estimate is longer but after a small reward it is shorter
□ Turns out high calorie consumption actually led to less patience, which is not what they expected
Anxiety vs Fear response
They share many common physiological features, but they can be differentiated:
Fear responses are elicited by specific stimuli and tend to be short lived
Fear responses decrease when a threat has been removed or dissipated
Anxiety may be experienced in the absence of a direct physical threat and typically persist over a longer period of time
Extinction of a conditioned fear response
e.g. presenting the tone repeatedly without the shock, resulting a gradual decrease in the conditioned fear response
Extinction is the basis for graded desensitisation training in psychological practice
Systematic desensitisation
Developed in the 1950s by Dr Joseph Wolpe
attempts to replace an anxiety or fear response with a relaxation response through a classical conditioning procedure
You gradually associate, through repeated pairing, a fear-arousing stimulus with a state of relaxation, in a series of graded steps
Really important that you replace the anxiety or fear with relaxation response before upping the stimulus
3 ways conditioned fear returns
§ After the passage of time (Spontaneous recovery)
§ Changes in context (Renewal effect)
§ Stress (Reinstatement effect) - one of the more common ones
interpreted as evidence that the original ‘fear memory’ is not deleted, or erased, but rather inhibited during the extinction phase of conditioning experiments
Fear conditioning neural network structures
Include the amygdala, hippocampus, ventromedial PFC, dorsolateral PFC, and striatum
Cognitive regulation (neurology and 2 strategies)
the dorsolateral prefrontal cortex (dlPFC) regulates fear expression through projections to the vmPFC, which in turn inhibits amygdala activity
Strategies include:
§ Reinterpret the significance of an event (cognitive reappraisal)
§ Focus attention on the less fearful aspects of a situation (selective attention)
Active coping (basic idea)
argued to be the most commonly used ‘untaught’ method we use to regulate our emotions
strategies involve an awareness of the stressor, followed by attempts to reduce the negative outcome
Learning an action to avoid a fearful event or diminish the fear response
Active coping (neurology)
○ During active coping, info from the LA (lateral nucleus) is routed not to the CE (central amygdala), which drives fear expression, but to the B (basal amygdala), which in turn projects to the striatum. The striatum is thought to reinforce instrumental action taken during escape- from- fear or avoidance learning
Reconsolidation period
○ Diminishes conditioned fear expression through alteration of the original CS-US association stored in the LA
Linked to the idea that immediately after learning there is a period of time where a memory is fragile, less permanent
○ During the consolidation period, you actively seek to disrupt the formation of the memory
○ Or, if you are past the consolidation period, you look to modify or inhibit, but not eliminate, the memory, by actively retrieving the memory
○ The act or retrieval makes the underlying memory trace fragile again, called the reconsolidation period
- potentially allowing you to block the memory completely
Kindt et al. (2009), Schiller et al. (2010) and Debiec and LeDoux (2004)
were the first to show that in humans you could use propranolol to block the return of fear
Still not clear what the mechanism for propranolol’s effects are
Anxiety and Fear
Several prominent theories of Anxiety Disorder propose that dysregulation of the neurocircuitry of conditioned fear may be central to the disorder
trait anxiety is associated with heightened amygdala activation and elevated fear expression
Anxiety also impairs extinction learning and retention, as well as the regulation of emotional responses via cognitive strategies
○ These deficits appear to stem from impairments in the regulation by prefrontal cortex of the amygdala ○ For example, anxious patients exhibit reduced prefrontal activation during or before fear extinction, and require heightened prefrontal recruitment to successfully reduce negative emotion with cognitive reappraisal
Cognitive effects of Anxiety (info processing biases)
two key cognitive information processing biases:
- A bias to attend toward threat-related information
- A bias toward negative interpretation of ambiguous stimuli
Anxiety and Attention Threat Study (ambiguous faces + homphones)
For stimuli with more than one potential interpretation, people with anxiety have a tendency toward a more negative perception
§ Ambiguous facial expressions (Richards et al., 2002)
§ Face-voice pairings
§ Verbal homophones
□ Die or Dye
When evaluating the probability of future life events, individuals with anxiety will judge the probability of negative outcomes as far more likely than non-anxious controls
Anxiety and economic decision making
hyperactivity of the amygdala, while attending to, evaluating or anticipating negative stimuli, contributes to heightened cognitive and affective responses to a potential threat stimuli
Prefrontally mediated cognitive and affective regulation processes also appear to be impaired in anxiety, reducing the ability to modulate these pre-existing tendencies
Uncertainty
Across species, stimuli that are unpredictable will elicit greater anxiety
people with anxiety will show threat-related information processing biases that alter their decision making
Humans as a general trait will be risk averse
For all, the amount of attention given to the aversive choice option predicts the likelihood of avoiding that option
Importantly, when the decision paradigm requires the anxious participant to make a choice for another person, they are less risk averse
Risk (Dohmen et al. 2011)
§ Analysed the relationship between the response to the 10 point risk question and other variables in 22,000 participants
§ Women were less likely to take risks than men
§ Increasing age was associated with less risk tolerance
§ Greater height was associated with greater risk tolerance
§ Having a mother with higher academic achievement, and to a lesser extent a father, increased risk tolerance
Anxiety and risk avoidance (physiology)
Evaluating your own physiological response to a risky choice appears to be critical to risk avoidance in anxiety
If your evaluation of an option includes increase sympathetic nervous system responses (e.g. BP, HR, SCR increases), then anxious participants are more likely to avoid these option
Hence why casinos sometimes give free alcohol to increase likelihood of risky decisions
Ambiguity
multiple possible outcomes with unknown probabilities
§ Like with the attentional bias effect, decisions between ambiguities options will illicit greater anxiety, and people with anxiety will show greater avoidance of ambiguous decision making - e.g. choosing a clear urn to an opaque one
§ In ambiguous decision making situations, people with anxiety will overestimate the probability of negative outcomes, and their subjective cost
Car vs Train example
Framing & Anxiety
§ Anxiety, train and clinical, is associated with greater framing effects in their decision making
§ Argued to be driven by loss aversion, where the increased sensitivity to the certain loss engenders an avoidant response, increasing risk taking behaviour
Loss Aversion
§ The degree to which avoiding losses is prioritised in comparison to achieving equivalent gains
§ Anxiety, of all forms, is associated with increased loss aversion
Emotions shape decisions via the depth of thought
negative emotions increase the depth of information processing, signalling when a situation demands additional attention
§ Not always a good thing
Increased focus on anchoring effects
relative to neutral state participants, angry participants allocated less to welfare recipients, and sad participants allocated more
- an effect that could be eliminated when given greater unrelated cognitive demands
Intervening to reduce emotion effect (4 strategies)
Time delay (simplest)
Suppression (ineffective)
Reappraisal (one of the best strategies)
Increasing awareness of misattribution (can often be quite difficult)
Burden of health transition
□ 90’s - most burden was from communicable diseases
□ 00’s and towards 20’s - burden is shifting from communicable disease to more non-communicable/behaviour-related diseases
® Behaviour is a huge component
Habit (definition)
§ The exhibition of a learned behaviour that was insensitive to changes in regarding outcomes
Common features of habit learning (human and animal)
§ Repeated responding that forms context-response associations in memory
§ Automatic habit performance that is relatively insensitive to changes in the value of the response outcome
- important distinction to consider is that humans engage in much repetition of behaviour
§ E.g. High levels of repetition in daily activities
□ Probably about 40% of what we do every day is habitual
Habit creation (vs. repetitious behaviour)
Typically arise due to an interface with goal-related behaviour
§ Goals direct human action by providing a definition of a desired outcome
§ Repetitious behaviour is usually, but not necessarily, goal related and can be distinguished from habit behaviour because it does not persist when the value of the repeated behaviour is absent
Automaticity
○ All habits have a level of automaticity, but not all automatic responses are habits
§ E.g. Startle reflex is an automatic response, but not a habit
§ E.g. Nail biting - negative reinforcement by self-soothing or distraction
□ Also alcohol at social functions easing social anxiety
Difference between habits and other automatic processes
§ Priming
§ Classical conditioning
§ Non-associative learning
○ Habit automaticity is specific to a particular response or behaviour
Implementation intentions
Often referred to as automated goals
Will only influence behaviour insofar as they are consistent with someone’s motivation level or intention
§ Getting people to commit/set an intention will increase the likelihood of otherwise non-habitual behaviours
□ E.g. The dentist asking you when you would like to have your next appointment
□ Don’t work with automatic/frequent behaviours like seatbelts
Habit representation
Perception of the relevant context cue automatically activates the mental representation of the habitual response
Habits can be triggered/cued in deliberate or inadvertent ways
It is generally easier to break a habit if you are conscious of it
A habitual response is the cueing of mental representation that contains both the features of your response, but also the features of perceptual information that cues your response
Habit insensitivity
Habit performance is characterised by the insensitivity to outcomes
One consequence for this finding is that repeated behaviour over time will become more habitual and less goal dependent
Habit strength will also interact with behavioural intentions
Dual Process models argue that habitual behaviour exists because it offers a greater level of efficiency
Habits are a ready default setting for behaviour that allow us to respond, unless we are particularly motivated and able to engage in more deliberate and specific goal pursuit
Habit formation
Habits develop through instrumental learning
§ Reward responses will be repeated - Thorndike
Habitual responding continues to be influence by motivational processes
- Pavlovian Context Cues
- The motivational effect of these cues is not related to the value of the outcome
Habits develop most readily when rewards are provided on an interval schedule
- Most ‘checking’ behaviours are like this - e.g. Checking your phone for messages
- Also gambling and ‘arguably’ social media algorithms - interval schedules
Habit formation pt II
○ Repetition will not always lead to habit formation
§ If the repetition of a behaviour includes decision making, it will generally prevent, or slow, the formation of habitual behaviour
§ Deliberative decision making protects against habit formation even when you respond repeatedly to the exact same cue
Human Research has typically not seen a relationship between the extent of training (or repetition) and greater expression of habits
Habit circuit
converging evidence indicates that habitual behaviour is mediated by circuits that link cortical brain areas and the basal ganglia
§ The basal ganglia is a subcortical structure, that houses a collection of subcortical nuclei
§ Dorsolateral striatum appears critical to acquiring new habits
§ Dorsomedial striatum appears critical to goal-directed control
□ This info comes from animal research
Habits > Goal Pursuit (balance factors)
The balance between habits and goal pursuit can be influenced by a number of situational factors
§ Distraction
§ Time pressure
§ Task ability (or lack thereof)
§ Self-control
Habits will trump goal-directed behaviour when they lack the ability and motivation to engage in deliberative decision making
Acute and chronic stress will increase the reliance on habits
§ Time pressure, reduced self-efficacy = more likely to rely on habits
Habit and Awareness
○ People have some awareness of their habitual responses, but they have poor awareness of the cueing mechanism that activates the habit
One aspect of this lack of awareness is that participants with stronger habits will have a greater tendency to infer that behaviour was guided by their behavioural intentions (or goals)
Over time, goals can be formed as a consequence of habitual behaviour, rather than preceding it
Changing Habits (2 aspects)
○ Behaviour change techniques have difficulty changing habitual behaviour because the responses do not reflect a persons stated intention or desire
○ The major challenge is that habitual behaviour continue to be activated automatically by recurring environmental cues
○ In response, behaviour change techniques have focused on two aspects
1. Impede the automatic cueing of old, unwanted habits
2. Encourage the repeated use of new, desired behaviours to the point they become habitual
Behaviour change techniques to reduce interference from old habits
- Invoked thinking
- Inhibitory plans
- Attempting to link specific inhibitory plans to time or environmental cues that are linked to the habitual behaviour
- Exposure Management or habit discontinuity
Robbins et al. 1973, 1993 - Vietnam Vets
Of those who had reported being dependent, only 5% had relapsed within 10 months of return
® For context, normal heroin relapse rates are around 70%….
§ Taking them out of the environment to a completely different one with removed cues and stressors was highly effective (just naturally)
Encouraging Formation of Desired Habits (past)
○ Behaviour change techniques to encourage the formation of desired habits have not always been built upon the concepts of habit formation: repetition, stable context, appropriate reward schedules
- Repetition required can be extensive
- Reminders can reduce automaticity
Neuroimaging is…
- Expensive
- Complicated
- Correlational
○ Prior to doing a brain imaging experiment, ask yourself if you have questions about the brain, behaviour, both, or something else