PAPEZ - 1937 - CIRCUIT THEORY OF
BRAIN AND EMOTION - emotional
responses have a network of brain
regions, such as the hypothalamus,
anterior thalamus, cingulate gyrus and
the hippocampus
MACLEAN - 1949 - extended
this emotional network to include
the amygdala, orbitofrontal
cortex and portions of the basal
ganglia. the LIMBIC SYSTEM as
the emotional brain
EARLY
ATTEMPTS
tended to
view emotion
as a unitary
concept that
could be
localised to
one specific
circuit, such
as the limbic
system
LATER
ATTEMPTS
we no longer think
that there is only one
neural circuit of
emotion. there are a
number of regions
that play a role in
different emotional
tasks.
AMYGDALA - in the
medial temporal lobe.
amygdala damage
influences subtle deficits
in fear processing
IMPLICIT
EMOTI0ONAL
LEARNING
FEAR CONDITIONING - form of
classical conditioning where the
unconditioned stimulus is
aversive. light paried with foot
shock, light presented alone will
eventually starle the rat. can
become UNPAIRED AGAIN,
called EXTINCTION
damage tp the amygdala
impairs conditioned fear
response. the amygdala
serves as a convergence
area for information from
multiple brain regions,
allowing for formations
underlying fear
conditioning.
patients with amygdala
damage fail to demonstrate an
indirect CR. patient S.P. had
bilateral amygdala damage,
had her right amygdala
removed to relieve epilepsy.
S.P. UNABLE TO
RECOGNISE FEAR
LE DOUX - 1996 - low road,
pathway in which sensory
information about a stimulus is
projected to the thalamus,
sneds a signal directly to the
amygdala. ALSO.. high road,
sensory information projected
onto the amygdala through
another cortical pathway
referred to as the high road.
DOUBLE DISSOCIATION betwen
patients who have amygdala
lesions and patients with
hippocampal lesions highlights the
fact that the amygdala is
necessary for implicit expression of
emotional learning, but not all
forms of emotional learning and
memory
EXPLICIT
EMOTIONAL
LEARNING
AND
MEMORY
the amygdala interacts with
other memory systems, such
as the hippocampal memory
system, when there are
emotional events or
information.
the amygdala can
enhance the strength of
explicit or declarative
memories for emotional
events my modulating the
storage of these
memories
the amygdala is critical for the
ability to show a conditioned
fear response during fear
conditioning. the amygdala is
critical for the indirect
expression of a fear response
when the emotional learning
occursd explicitly
an arousal response
influences the ability to
store declarative or
explicit memories.
memory is enhanced
by arousal
SAPOLSKY - 1992 -
extreme arousal or
chronic stress may
actually impair
performance of the
hippocampal memory
system
SOCIAL
RESPONSES
the human amygdala is
responsible for normal responses
to social stimuli, for example, facial
expressions. amygdala involved in
processing the facial expression of
fear with S.M.
ADOLPHS ET AL. - 2005 -
S.M. didn't derive
information from the eyes.
the amygdala appears to be
an integral part of a system
that automatically directs
visual attention to the eyes
when encountering any
facial expressions
IMPLICIT
ASSOCIATION TEST
- GREENWALD -
1998 - measures the
degree to which social
groups are
automatically
associated with
positive and negative
evaluations
PHELPS ET
AL. - 2000 -
amygdala was
activated
when white
americans
viewed
unfamiliar
black faces
subjects who showed more
racial bias measured by the
IAT showed more amygdala
activity during the
presentation of black faces.
HOWEVER, It might be
critical for the indirect
evaluation of race, important
for same vs. other race.
OTHER
BRAIN
AREAS
AND
EMOTION
ANGER
BLAIR ET AL. - 1999 - the
RIGHT ORBITOFRONTAL
CORTEX active with angry
but not sad faces
SADNESS
BLAIR ET AL - 1999 -
LEFT AMYGDALA
AND RIGHT
TEMPORAL POLE
associated with the
intensity of sad
expressions
DISGUST
CALDER ET AL -
2000 - INSULA is
essential to both
detection and
experience of disgust.
insula damage unable
to detect disgust
SUMMARY
earlier research and theories viewed
emotion as seperate from cognition, it
became clear that they could be studied
and understood seperately