Biological Approach:
- Canli et al.
- Dement and Kleitman
- Schachter and Singer
Describe Assumptions:
- Emotions, behaviour and cognition are controlled by biological systems and processes,
such as evolution, genes, the nervous system and hormones.
- Emotions, behaviour and cognition can be investigated by manipulating and measuring
biological responses, such as eye movements, brain activity and pulse rate.
- Behaviour, cognitions and emotions can be explained in terms of the working of the brain
and the effect of hormones
- Similarities and differences between people can be understood in terms of biological
factors and their interaction with other factors
- Behaviour can be explained via the brain, for example the amygdala is involved in the
processing of emotion and memories associated with fear
Outline two assumptions, including any example in your answer:
- Behaviour, cognitions and emotions are controlled by biological systems and processes.
For example, Schachter and Singer looked at the role of the biological hormone
adrenaline in emotion.
- Similarities and differences between people can be understood in terms of biological
factors. For example, the study by Canli looked at memory of emotional stimuli, and
there were similarities and differences between memory scores which could be explained
by the biological factor of amygdala activation.
Canli et al.
Psychology being investigated:
- Emotions: do more strong emotionally intense scenarios/scenes increase the likelihood
the event will be remembered?
- Amygdala - the amygdala was investigated in relation to its links with memory. They
particularly investigated whether highly emotionally intense scenes were likely to be
remembered more than barely emotionally intense scenes.
The amygdala was investigated about its links with memories; It is part of the brain in the
temporal lobe / part of the limbic system; The amygdala has different functions in
different hemispheres of the brain.
- Brain Scans - an fMRI is a non-invasive technique / measures brain activity; Radio waves
are coupled with a strong magnetic field to create the scan output; This allows a
, researcher to look at blood flow in the brain during mental activities / processing of
information
- Memory: is memory of an event enhanced when it is strongly emotionally intense?
Background:
- Two types of scans - functional & structural. Structural scans take detailed pictures of the
brain structure, whereas, functional scans show activity levels (patients are placed in a
scanner that sends a strong magnetic field through their head, the magnetic field causes
the nuclei in hydrogen molecules in the brain to spin in a particular way and the scanner
picks this up).
- The role of the amygdala in enhancing declarative memory for emotional experiences has
been investigated in a number of animal, patient, and brain imaging studies.
- LaBar and Phelps (1998) suggested that emotional experiences are often better recalled
than non-emotional ones
- Emotional arousal appears to increase the likelihood of memory consolidation during the
storage stage of memory
- Brain imaging studies have shown that amygdala activation correlates with emotional
memory in the brain
- Canli et al. (1999) showed that participants who had a strong amygdala activation in
response to a set of emotional stimuli showed superior memory for those stimuli
Aim(s):
- To investigate if the amygdala is sensitive to varying degrees of emotional intensity to
external stimuli and whether the level of intensity enhances memory for the stimuli
- To investigate whether the degree of emotional intensity affects the role of the amygdala
in enhancing memory for emotional stimuli
- To show that emotive images will be remembered better than those that have little
emotional impact on an individual
Hypotheses:
- Emotionally intense stimuli will cause greater activation of the amygdala and lead to
better recall than less emotionally intense stimuli
Procedure:
- Participants gave informed consent and were aware of the nature of the experiment
- Participants were placed inside an fMRI scanner. During scanning, participants viewed a
series of 96 scenes that were shown by an overhead projector and a mirror to ensure
participants could see the image.
- The order of scenes were randomised across the participants
, - Each picture was presented for a period of 2.88 seconds. Then, there was an interval of
12.96 seconds where participants focused on a fixation cross
- When the fixation cross appeared participants were to indicate their emotional arousal by
pressing a button with their right hand.
- They could choose from 4 buttons ranging from 0 (not emotionally intense at all) to 3
(extremely emotionally intense)
- Brain activity data was collected by a 1.5 Tesla fMRI scanner
- Three weeks later, participants were tested in an unexpected recognition test in the lab.
- They viewed all 96 previous scenes and 48 foil scenes (matched the previous images in
valence and arousal characteristics)
- Participants were asked whether they had seen each scene before (options were: not
remembered/forgotten, familiar, and remembered).
Findings:
- Participants’ experience of emotional intensity correlated well with average rating of
emotional valence and arousal.
- Amygdala activation was significantly correlated with high ratings of individually
experienced emotional intensity - provides evidence that amygdala activation is related to
the subjective emotional intensity and the perceived arousal is associated with amygdala
activation.
- Follow-up memory task indicated memory performance was significantly better for
highly emotionally intense scenes.
- Scenes rated mild to moderate (0-2) had similar distributions of items that were forgotten,
familiar, or remembered. Whereas, images rated as highly emotional were recalled better
- more were remembered/familiar.
- Left amygdala activation predicted whether individual stimuli would be forgotten, appear
familiar, or be remembered. Little amygdala activation was associated with the
participant forgetting stimuli, and high amygdala activation was associated with
familiarity/remembered.
- Amygdala activation was significantly bilaterally correlated with emotional arousal (as
emotional intensity increased, amygdala activation increased; as emotional intensity
decreased, amygdala activation decreased).
Key Quantitative:
- The average correlation coefficients between participants’ intensity ratings and normative
valence and arousal were -0.66 and 0.68 respectively. Participants’ ratings of emotional
intensity reflected the valence and arousal characteristics of the stimuli.
- Ratings of emotional intensity were similarly distributed across four categories (0 = 29%;
1 = 22%; 2 = 24%; 3 = 25%)
