Fear & Anxiety Flashcards
How do you define affective (emotional) experiences?
conscious states that are accompanied by particular changes in autonomic and somatic motor activity
William James said. . .
every object that excites an instinct excites an emotion
Instinctive behaviour are not just facial
expressions but also behavioural dispositions and actions.
Particular intepretations can be seen by animal drawings depicted (1) facial expressions and (2) autonomic reactions (appearing bigger, aggressive, ready to run)
Why do we fear what we fear?
- Emotional systems develop and change, exhibiting different contingencies during development
(i.e. what you were afraid of when you were 4 may completely differ to what you fear at 10/11) - What is the importance of knowing that emotional systems develop?
show that fear, though innate in a sense, is plastic but how?
also wanting to find neural basis of fear but also substrates
Explain the ‘sham rage’ study
Objective: Early experiments aimed to locate the origins of fear responses in the brain.
Method: Researchers performed brain surgeries where they selectively cut off parts of the brain in animals.
Findings: They discovered that “sham rage” (an intense and inappropriate rage response to non-threatening stimuli) occurred when the hypothalamus and thalamic regions were left intact. This indicated that these regions play a crucial role in generating rage responses.
Which brain regions are responsible for generating rage response?
hypothalamus and thalamic regions
Where is the amygdala located?
In the medial temporal lobe, specifically in the limbic lobe
Where is the amygdala located?
the amygdala is crucial for processing fear and assessing potential threats
the amygdala becomes active when making judgments about people, esp in determining if someone poses a threat or is untrustworthy
Distinguish b/w the functions of left and right amygdala
LEFT AMYGDALA: shows a general response to both implicit (subconscious) and explicit (conscious) threat assessments
RIGHT AMYGDALA: shows significantly more activity during explicit threat assessments compared to implicit
How does fear (experience and response) become associated with predictors?
the mice & rat study
Experiment was when you hear a tone =
followed by foot shock such that electrical shock was unpleasant.
Simple Pavlov conditioning to pair shock with the tone such that the tone will eventually induce fear (characterised by autonomic and physical (freeze reaction).
Found that they activate cortical regions that give rise to somatomotor and autonomic activity when foot-shock such that the tone will give the same response.
Sensory information converges and crosses pathways at the AMYGDALA.
Associative LTP for fear conditioning
Inputs of neutral sensory stimuli (like audio tone or visual) and primary reinforcers (pain, electrical shock, taste, touch) are strengthened such that they become associative
2 types: specificity & associativity
Distinguish b/w specificity & associativity
Specificty: ONLY those synapses tetanically active have LTP induced
Associativity: those synapses tetanically active that have LTP can also affect OTHER synapses not actie at the time so neuron becomes more responsive to more input
Results of specificity vs associativity
Specificity: Ensures that only the synapses involved in a specific learning event (e.g., tone paired with shock) are strengthened, leading to precise and targeted learning.
Associativity: Allows for the linking of stimuli, so that even weak or neutral stimuli can gain significance when associated with strong, salient stimuli (e.g., a tone becomes associated with a shock).
How does los of amygdala affect emotional responses?
Found that brain-damaged controls (unconnected to amygdala) had normal emotional response whereas amygdala (patient S.M) had identical performance on everything but the afraid person - real inability to recognise fear in facial expression. Also couldn’t really imagine it as well = no conception of what fear was like
Some approaches used to nomalise fear responses
1.re-learning the (mis)associations
2.Pharmacological intervention
What is the relationship between GABA and fear disorders?
Fear disorders are associated with decreased activation of GABA receptors. Despite GABA being a widespread neurotransmitter in the nervous system, GABA agonists (or more precisely, positive allosteric modulators of GABA receptors) can produce an anxiolytic effect, alleviating anxiety without significantly disrupting other bodily systems.
