Lecture 10: The Self

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Lecture 10 The Self
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Recap on Lecture 9.

• What is the Self?
• Is it subserved by a special process?
• 3. Is it subserved by a specific brain region?

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What is the self?
Kihlstrom Klein (1997) state the self
represents our own knowledge of ourselves, and
therefore should be considered in terms of the
manner in which knowledge is represented.
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What is the Self ? The Self as Self-Knowledge

• A Concept
• (The self is actually a fuzzy set of
  context-specific selves).

• A Narrative
• (which we construct, rehearse and relate
  to others).

3. An Associative Network (episodic and semantic
memory) Self-Semantics
4. An Image (a percept-based representation of
face, body and gestures) Self-Recognition
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What is the Self ? The Self as Self-Knowledge
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What is the self?
The Self and Memory Am I beautiful? Is George
Bush stupid?
Memory advantage for traits encoded in relation
to the self (Symons Johnson, 1997). However
only for traits and non-intimate other
comparisons.
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Is self-referential processing special?
The Self-Referential Effect in Memory
The self is a unique cognitive entity with
special mnemonic powers (Rogers et al.,
1977). It is powerful, but ordinary
(Greenwald Banaji, 1989) the memory
enhancement afforded to self-referential
processing can be explained as an extension of
the Levels of Processing effect (Tulving).
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Is self-referential processing special?
LOP differences associated with activation
in Left Prefrontal Cortex (LPFC)
If nothing special about self then just greater
activation in LPFC.
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Is self-referential processing special?
Kelley et al. (2002)
Showed a self-referential effect in trait memory.
Left Inferior Prefrontal
No difference between Self and Bush in region
associated with Level of Processing effect.
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Is it subserved by a specific brain region?
Kelley et al. (2002)
MPFC
Significant difference in MPFC for
Self. Self-Referential processing linked to a
specific brain region.
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Is MPFC Activity Related to Memory?
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Summary of Self-Reference Effect in Memory

• 1. Not a Level of Processing effect.
• 2. Greater activation in MPFC.
• Evidence for Special Cognitive Entity Specific
  Brain Region.
• BUT.
• Strongest effect for item memory when traits
  used
• the referent other is non-intimate.
• Traits may already be highly organized in
  relation to
• the self.
• May therefore just be measuring LTM differences.

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• What are we measuring in MPFC?
• In trait studies we are more likely to endorse
  positive traits than negative traits as being
  self relevant (Taylor Brown, 1988).
• Therefore, MPFC activation could reflect
• Self-referential processes.
• Item valence (positive vs. negative)
• An interaction between a. b.

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Moran et al. (in press) JoCN.

• Subjects responses with 4-point
• Likert scale to assign self-relevance
• to the trait word
• Not at all like me
• Through to
• 4. Most like me.

lazy
1250ms
750ms
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Results
MPFC
MPFC
vACC
MPFC activation linked to self-relevance. vACC
activation linked to valence. Greater for
positive, self-relevant items.
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Do you have to directly self-reference to
activate MPFC?
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Are You Like Me?
How pleased?
Use knowledge about self to infer the mental
states of similar others
How symmetrical?
How pleased?
How symmetrical?
Mitchell et al. (2005) JoCN.
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Similar v. dissimilar targets
Mitchell et al. (2005), JoCN.
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Summary of Evidence for MPFC Involvement in
Self-Referential Processing
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Sumary Evidence that the self is a special
cognitive entity. Self-Reference Effect in
Memory. Not just a LoP effect. Evidence that
self-referential processing engages a distinct
neural system in the ventral portion of the
medial prefrontal cortex. This region
differentially processes relevance (MPFC) from
affect (vACC). Caveats General problem with
methodology Directed question. Shouldnt self
be engaged for unconscious processing as well
(Mitchell et al., 2005)?
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The Self as a Percept - Self-Recognition
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What is the Self ? The Self as Self-Knowledge
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What is the self?
Damage to different neural structures leads to an
altered Self
Feinberg (2001)
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• Self as a Percept
• Body Recognition
• Face Recognition

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Asomotognosia - lack of body recognition
Mirna Woman in her 70s with stroke damage to
large portion of her right hemisphere, including
motor and somatosensory cortices.
Mirna suffered from hemispatial neglect. This
condition is manifest in neglect of information
present in one hemispace. Mirna neglected
information in the left visual field.
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In addition to neglecting the left side of space,
she also neglected the left side of parts of her
own body. Mirna denied that her left arm belonged
to her. An example of her interaction with her
neurologist Dr. Feinberg Feinberg Take a good
look. What is it? tapping the back of her
hand. Mirna The back of your hand. Feinberg
Suppose I told you it was your hand. Mirna I
wouldnt believe you. Mirna goes on to claim
that the hand actually belonged to her dead
husband!
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In most patients with asomatognosia the good
hand can trace the connection of the limp arm
back to their own shoulder and yet remain
convinced that is it not their arm! One patient
explained this as my eyes and my feelings
dont agree, and I must believe my feelings. I
know they look like mine, but I can feel they are
not, and I cant believe my eyes. Feinberg
(2001), pp11.
Interestingly, Feinberg notes that of over 100
cases of asomatognosia, none had been caused by
damage to the left hemisphere. Why?
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The Interpreter Module in the Left Hemisphere
According to Gazzaniga the left hemisphere
interprets information received from the senses
and uses this to explain events and to attribute
their underlying causes. Insertion of an
interpreter into an otherwise functioning brain
creates many by-products. A device that begins
by asking how one thing relates to another, a
device that asks about an infinite number of
things, in fact, and that can get productive
answers to its questions cannot help but give
birth to the concept of self. Gazzaniga, 2000,
p.130).
In asomatogonosia the left hemisphere receives no
input from the damaged right hemisphere and so
attempts to construct a version of reality based
upon what it knows, even if this is bizarre.
Therefore, I cant feel it or move it so it
cant be mine! Similar explanation for Capgras
delusion.
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Self-Recognition
Self-recognition occurs in humans around the age
of 18 months to 2 years. This ability has
also been investigated in other species
(Dolphins, Macaques Chimps.. and McGeorge)
using the Mirror Test (Gallup).
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Where in the Brain does this Occur?
MPFC (Kelley et al.)
Interpreter Module (Gazzaniga)
Right FFA (Gauthier et al.)
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How to Clarify this Issue
Callosotomy patients provide and excellent
mechanism to test lateralized processes.
Dark area Represents where Corpus Callosum
should be
JW
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Morphed Face Stimuli
Generate a set of images from JW - MG at 10
intervals from 0 to 100
Percent of Self in the Image
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Morphed Sequences Used
Self
Familiar Other
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Testing Self-Recognition in a Split-Brain Patient
Image Presented for 250ms
Lateralized Response
Lateralized Response
Yes
Yes
No
No
Conditions Is it You? Is it
Mike?
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Results
Left hemisphere self-recognition - gt40 Right
hemisphere self-recognition - gt80
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Conclusion

• Self-Recognition is possible in both
  hemispheres
• BUT
• LH important in execution of self-recognition
• Also suggests that self-recognition is
  functionally
• dissociable from general face processing.

Turk et al. (2002) Nature Neuroscience, 5 (9),
841-842.
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But what about MPFC and self-recognition? Split-B
rain study not sensitive enough to ascribe
regional function to self-recognition. What
about fMRI Research? Study by Uddin et al. (2005)
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Results
SelfgtOther Contrast Classed 60, 80 100
images as self Classed 0, 20, 40 images as
other. Used this to define ROI then looked at
activation in these ROIs as a function of self.
Self Appears to be Lateralized to the RH. No MPFC
Activation for Self.
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• Problem Blocking different levels of self to
  generate ROIs.
• Blocking the data in this way assumes that brain
  regions associated with self-recognition are in
  some way activated linearly as a function of the
  amount of self in the image.
• Is 60 self more like self than other?

Split-Brain data suggest that in RH
self-recognition occurs only if at least 90 self
is presented.
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Another (Unpublished) fMRI Study Turk et al.
(2006) Conference presentation.
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SelfgtZero
-3, 57, 12
Self-Recognition appears to match with RH
split-brain data (gt80 self). Also shows
differential activation in MPFC for recognition.
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• Summary of Self
• Issue of Definition of Self (Semantics vs.
  Recognition).
• Self-Semantics appears to reflect unique
  cognitive entity in specific brain region.
• Self-Recognition may also activate this region
  (but see Uddin study?)
• See Feinberg (2001) for a notion of a distributed
  self.
• Also the idea of LH interpreter drawing
  information from a distributed network to create
  a sense of self.

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Refs Feinberg T (2001) Altered Egos How the
brain creates the self. OUP. Turk et al. (2003)
Annals of NY Acad. Sciences, Vol. 1001. Uddin et
al. (2005) NeuroImage, 25, 926-935.