Fear and Anxiety Flashcards
What is anxiety
Anxiety is what we feel when we are worried, tense or afraid - particularly about things that are about to happen, or which we think could happen in the future.
Anxiety is a natural human response when we perceive that we are under threat. It can be experienced through our thoughts, feelings and physical sensations.
~6% of people in the UK report experiencing generalised anxiety disorder (GAD), Phobias (2.4%), OCD (1.3%) and Panic Disorder (0.6%)
It is experienced by many people in stressful situations = normal, becomes a problem when affects our lives
Research bases for studying fear conditioning and anxiety in humans?
Duit et al., 2015- meta-analysis
- Fear and anxiety are grounded in a defence motivational circuits
- Fear in studies on animal models BUT in human fear conditioning the same neural circuits are found to be active
- HYPERactivity of amygdala and insula is found in phobic disorders, and in (PTSD)
- HYPOactivation in ventromedial prefrontal cortex (vmPFc) during extinction learning
Freezing
The interruption of all locomotion and gross body movements during the presentation of the CS
Conditioned emotional response
Suppression of ongoing instrumental behaviour (e.g. press lever get food)
Startle potentiation
Amplification of the startle reflex that is elicited by a loud auditory probe
Defense system
Gets activated by cues that signal threat (according to the defensice-activation hypothesis); the threat of shock activates them, regardless of the cue’s prior hedonic valence (the unpleasant thing will elicit startle reflex no matter if it was paired with threat or safety cue) Bradley et al (2005)
Can be measured by blinking, heart rates, skin conductance (sweating)
Visual analogue Scale (VAS)
People (unlinke animals) can tell us their subjective reports of fear.
Startle reflex
In humans- blinking
Present when cues which predict immediate painful shock are presented.
Grillon and Davis show it:
blinking more frequent in conditonig when cues presented are indicating electric shock vs. in cues which predict no shock.
Strong vs. weak situations
A strong situation is one in which the stimuli that are encountered by an individual are unambiguous and predict or constitute a clear hedonistic event. —> All people are likely to react in the same way casue it’s obvious that the threat will come.
A weak situations are situations characterized by high ambiguity or uncertainty. –> Can provide more insight about the individual differences of fear learning patterns.
Fear vs anxiety
Fear: Used to cope with danger; an intense urge to defend oneself, primarily by getting out of the situation.
Increased heart rate, feeling more alert after it passes release of hormones to relax= shakes. (post-stimulus)
Anxiety: feeling of intense worry, tension or being afraid; doesn’t come from direct danger (more generalised cues); makes coping with situations harder. General state of distress, general arousal but no specific physiological cue (pre-stimulus)
The main difference: Fear has an identifiable stimulus which caused it.
ÖHMAN, A. (2008).
Individual differences in the aetiology of anxiety
Only a small percentage of people who experience a traumatic event develop anxiety disorder (Engelhard et al., 2008).
Stress-diathesis model of psychopathology:
- Genetic differences in SNPs coding for serotonin and dopamine system functions (Londsdorf et al., 2010)
- High threat-related amygdala reactivity (Hariri, 2009)
Issues with fear conditioning? to be deleted IGNORE
- Fear conditioning is adaptive
Why is fear conditioning adaptive?
In accordance with the adaptive nature of fear conditioning, in laboratory studies mostly everyone will learn to exhibit fear upon confrontation with a cue (CS) that reliably predicts the occurrence of an aversive outcome (US); it is a rather robust and reliable phenomenon.
Fear is good and in line with the theory of evolution. It makes sense to fear fearful stuff and to want to avoid them and learn about them fast.
Pathological fear and anxiety are (by definition) characterized by behaviour that disproportional to the actual danger.
Issues with fear conditioning?
- Fear conditioning is adaptive
- Current work on fear conditioning in humans tends to ignore behaviour: this is a problem because anxiety is a behavioural dysfunction.
- Moslty the ‘strong’ situations ar measured ignoring the ‘weak’ ones.
Why is the ignorance of behaviour (avoidance) an issue in fear conditioning studies explaining anxiety?
Emotional disorders are essentially behavioural dysfunctions: A tendency towards avoidance behaviour is one of the diagnostic criteria for many anxiety disorders.
