Mirror Neuron System

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Transcript Mirror Neuron System

Cognition & Development
3. Development of social
cognition
For info
Biological explanations of social
cognition
- Mirror neurons
Genetic theories
• Kanner (1943) originally suggested that autism
had a genetic component. Rutter (1999) also
proposes that as the rate of autism in siblings of
children with autism was 6% (much higher than
the national average) it is clear that there is a
substantial familial clustering of autism.
Although this could reflect shared environmental
factors, a percentage as high as this points to
the likelihood of a family-related, genetic
component.
Twin studies
Concordance rates for MZ (Monozygoticgenetically identical) twins is far higher than for
DZ (Dizygotic non-identical) twins. So if one
member of a twin is autistic, the probability that
the other will also be autistic depends on
whether they do share all their genes (MZ’s) or
only half their genes (DZ’s). Rutter (1999)
suggests that several genes are involved,
working in combination.
However…
• The prospect of finding autism in one
member of a MZ pair is very remote
(Mitchell, 1997). If autism is not caused
solely by genetic factors then there must
be an environmental component.
• Piven & Folstein (1994) found that 30% of
parents with an autistic child show at least
some autistic mannerisms.
Activity-Copying behaviour
Psychology video camera
and your mobile phone camera
Copying Behaviour... “Naturalistic Observation”
• In pairs go out into the college and use your mobile phone
camera/college flip-cameras to video/photograph examples of
people displaying ‘copying behaviour’ , i.e. copying each
other..
• It may be subtle or really obvious, e.g. yawning, crossing
arms, queuing, etc.
• Make sure you get consent before bringing back the footage
(i.e. ask the participants!)
• When collected return to the classroom and show them to the
• These will then be uploaded and shown to
the class next lesson..
“Mirror Neuron System”
• Research shows that dysfunction of the
Biological ‘mirror neuron system’ in
humans brain might be a core deficit in
autism, the socially isolating condition.
Here, we review the role of this system in
social cognition..
• Ever yawn when seeing somebody else
yawn? Ever in line at a fast food
restaurant and find yourself desiring and
ordering the same sandwich the person in
front of you orders?
Activity: in groupsdiscuss why you think
you yawn/copy other
people’s actions...
Watch video clip explaining connection
between Mirror neuron system &
autism
clip 1 intro
clip2 part 1
clip 3 part 2
clips
• http://www.bing.com/videos/search?q=mirror
+neuron+system&view=detail&mid=8D04BBC
9F9C0FAD6037C8D04BBC9F9C0FAD6037C&fir
st=0
• http://www.youtube.com/watch?v=Sv1qUj3M
uEc
• Maybe there's a good reason these are called
•
"monkey see, monkey do" actions.
Rizzollati (1996) studied macaque monkeys and
discovered a curious cluster of cells in the
ventral pre-motor area of the brain's frontal
lobes (an area part of the larger pre-motor
cortex-see diagram) while probing their brains.
• This area of the brain is
primarily linked to planning
and initiating movements.
These odd brain cells, which
seemed at first to only be tied
to performing actions or
watching others perform the
same actions, for brain scans
showed that this cell cluster
fired during these events.
Mirror neuron cells
The cells seemed to reflect the actions in the
other monkeys almost like a mirror reflects one's
image. They reacted the exact same way when
the monkey grabbed a peanut or watched
somebody else grab a peanut. It even became
easy to predict which specific neurons would fire
based on which specific activity the monkey was
observing and processing. Because of this
reflective property, Rizzollati (1996) dubbed this
cluster of cells "mirror neurons."
Excited by this newly discovered cluster of
cells research (e.g. Ramachandran et al,
1999) has attempted to test the existence
of mirror neurons in humans. They
discovered that not only did the mirror
neurons reflect actions, they were found
to mirror emotions and sensations, which
would give humans the ability to have
empathy for others (see diagram)…
Role of ‘Mirror Neuron System’ In Humans
Mirror neurons
Observation of behaviour (e.g.
emotions) of other people
Social organisation of
behaviour (e.g. empathy)
Copy behaviour
• "Mirror neurons suggest that we pretend to be
•
in another person's mental shoes," said Lacoboni
(1997), "In fact, with mirror neurons we do not
have to pretend, we practically are in another
person's mind."
Since their discovery, research has linked
mirror neurons to mental disorders like autism.
Since autistic people have difficulty displaying
empathy for and communication with-others
around them, perhaps these brain cells are
malfunctioning in these individuals.
‘Mirror Neuron System’ Hypothesis
and Autism
Evaluation
Support
• Ramachandran et al (2000) used an
•
electroencephalogram (EEG) to measure children's brain
waves.
An EEG component called the MU wave is blocked
anytime a person makes a voluntary muscle movement,
such as opening and closing one's hands. The MU wave
is also blocked when a person watches someone else
perform the same action. The researchers watched
for MU-wave suppression to monitor mirror neuron
activity.
Research
• Participants -Their first subject for their experiments was
•
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a high-functioning child with autism without severe
cognitive impairments.
Results - The EEG showed that the child had an
observable MU wave that was suppressed when he
made a simple, voluntary movement, just as in normal
children. But when the child watched someone else
perform the action, the MU wave was not suppressed.
Conclusion - The researchers concluded that the child's
motor command system was intact but that his mirror
neuron system was deficient.
• The researchers later conducted a more
systematic series of experiments in 10 highfunctioning individuals with autism spectrum
disorder and 10 age- and gender-matched
control subjects. They saw the expected
suppression of MU waves when the control
subjects moved their hands and watched videos
of a moving hand, but the EEGs of the subjects
with autism showed MU suppression only when
they moved their own hands. These findings
indicate that people with autism are likely to
have dysfunctional mirror neuron systems.
However… Criticism
• Pineda (2001) repeated the studies with 28 children,
7 to 17 years old, half of whom had autism, the other
half were typically developing children. In the
children with autism, the MU rhythms were
suppressed during both tasks. This may mean that
the mirror neuron system is fully functional but may
be disengaged in some activities.
• Suggested reasons for this include;
• Autistics have developed another coping strategy for
understanding others..
….also….
Oberman (2000) also found
that.. Familiarity is the real issue
…EEG recordings provided the first evidence
of normal mirror activity in children with
autism: People familiar to children with
autism may activate mirror neuron areas
of the brain in normal patterns when
unfamiliar people do not.
Their research…
• Procedure -Six videos were shown to a group of 26 boys, 8 to 12
years old; half had autism. Three videos showed images
representing varying degrees of social interaction: two bouncing
balls (the baseline measurement), three people tossing a ball to
themselves, and three people throwing the ball to each other and
off the screen to the viewer.
• The other set of videos showed people with varying degrees of
familiarity to the subjects: strangers opening and closing their hand,
family members making the same hand movement, and the subjects
themselves doing the same.
• Findings - EEG recordings showed that MU activity was suppressed
most when subjects watched videos of themselves, indicating the
greatest mirror neuron activity. For both groups, the measurements
showed a slightly lower level of suppression when subjects watched
familiar people in the video and the least when watching strangers.
This indicates that normal mirror neuron activity was evoked when
children with autism watched family members, but not strangers.
Summary…
• “This normal mirror neuron activity in
autistic children indicates that mirror
system dysfunction reflects an impairment
in identifying with and assigning personal
significance to unfamiliar people and
things” (Oberman, 2001).
Summary
“ The connection between mirror neuron
dysfunction and autism remains
speculative and it is unlikely that mirror
neurons are related to many of the
important characteristics of autism”
(Dinstein, 2008).
Sample exam questions
• “Critically consider psychological
research into the development of the
child’s sense of self, including theory
of mind (Baron-Cohen)”
(8+16 marks)
“Critically consider psychological
research into the role of the mirror
neuron system”
(10 + 14 marks)
Mirror neuron plan
A01
• Brief description of biological explanation of
autism (Kanner)
• Mirror neuron system – Rizzollati monkeys
• Link to humans-Ramahandran –
Support
• Ramahandran mu wave (2000) study
Criticism
• Pineda/Oberman, etc..
• Summary – really about familiarity
Finally..
• Complete exam question
• Do revision grid
• Complete any other sample exam
questions (see workbook)