studies and reviews Flashcards
dapretto et al 2006
fMRI where children observed and imitated facial expressions
Children with autism: less activity in the frontal part of the mirror-neuron system (inferior frontal gyrus ~ F5 ~ pars opercularis, Brodman area 44) when imitating or observing facial expressions. Especially in the right hemisphere.2. Activity in this area was inversely related to severity of social symptoms as measured with ADOS and ADI.
avanzini et al 2012
Mu rhythym reductions in EEG when observing others actions – ev becauses TT would not predict this as it claims the others mental states are represented theoretically, not embodied. Also shows differences between asd v nt
children with autism had less mu rhythym disruption in action observation condition
umilta et al 2001
found subset of MNs are active during action presentation, even when final part of movement is hidden, implies motor representaion of action can be internally generated even without full visual info, supporting hypothesis MN activation could be at the basis of action recognition
umilta et al 2008
Premotor neurons code for the goal of an action, rather than for the action per se.
reverse pliers
The capacity to use tools is based on an inherently
goal-centered functional organization of primate cortical motor areas.
kohler et al 2002
About 15% of mirror neurons responsive to the sight of an action also responded to the characteristic sound of that action
supports hypothesis of action meaning - If mirror neurons mediate action understanding,
then their activity should reflect the meaning of the
observed action, not merely its visual features.
iacaboni et al 2005
found actions embedded in contexts yielded a significant signal increase in the posterior IFG and adjancent ventral premotor cortex where hand actions are represented. This indicates the premotor areas thought to be responsible for action recognition are also involved in understanidng others’ intentions (inferring a new forthcoming goal - an operation the motor system does automatically)
gallesse and goldman 1998
link mirror neurons and simulation theory
rizzolatti et al 2004, 2010
MNS in monkeys and humans:
In monkeys only for action understanding.
Monkeys do not imitate a lot! (A popular misunderstanding)
In humans for action understanding and imitation.
The MNS transforms visual information into knowledge by using one’s own motor repertoire and experience.
The motor theory of speech perception:
brain areas involved in producing speech also participate
when hearing spoken language.
hamilton 2013
review showing current studies are very mixed and studies using weakly localised measures are hard to interpret. the better (fmri) atudies show group differences only when using emotional stimuli. overall, little evidence for global MNS dysfunction in autism. Suggests alternative STORM model where social top-down response modulation is abnormal in autism.
williams et al 2001
argue the MN autism hypothesis
argue in order for MN to become utilised for performing social cog functions inc imitation and ToM abilities, sophisticated cortical neuronal systems have evolved in which MNs are a key elelemnt. argue early dev failures of MN systems are likely to result in a consequent cascade of dev impairments characterised by the clinical syndrome of autism
fan et al 2010
EEG study against BMT. observed and executed hand actions. asd participatns failed to imitate but all MN activity appeared to be intact. Results were affect by experimental conmdition not goup membership and there was no interaction.
oberman and ramachandran 2007
aregue internal simulation mechanisms such as MNS are essential for normal development of recog, imitation, ToM, language, and empathy. argue dysfunctional simulation mechanisms may underlie scial and communication deficits in autosm
faDIGA et al 1995
using TMS
Motor Evoked Potentials (MEPs) recorded from the hand are enhanced during observation of hand actions.
~ MEPs are selectively enhanced in those muscles used to produce the action observed.
~ Listening to words enhances MEPs in the receiver’s tongue
cattaneo et al 2007
even with same goal different types of grasping activate different MNs. so propose a hierarchy action chain model. msny of these action constrained neurons have mirror neuron properties which fire selectively to the observation of the initial motor act. by activatiing a specific action chain from its very outset this mechanism allows the observer to have an internal copy of the whole action before its execution, enabling them to directly understand the targets intention. using electromyographic recordings they showed a similar chained organisation exists in NT children but it was impaired in children with aitism. they proposed that as a conseqwunce of this functional impairment, hfa children may understand others intentions cognitively but lack the mechanism for understanding them experientially
oberman, winkielman and ramachandran 2007
blocked mimicry, found biting pen impaired recognition of happy from neutral faces, supporting theory of internal embodied simulation for recognising emotional expressions
mcintosh et al 2006
using electromyography showed happy and angry faces. found autistic participatns were impaired in automationc mimicry but not voluntary mimicry. argue datra suggests autism is associated with an impairment in basic automatic social emotional process
di pellegrino et al 1992
First discovered in the premotor cortex of the macaque monkey, using single cell electrophysiological techniques
In addition to area F5 (premotor cortex), mirror neurones were also found in the parietal cortex : 1. premotor cortex (F5) 2. inferior parietal lobule (IPL, area FP
meltzoff 1977
imitation in neonates
mukamel et al 2010
Recently single mirror neurons were recorded in human patients.
They found mirror neurons all over the place, about 10% of cells recorded throughout the brain had mirror neuron properties.
gergley et al 2002
why did Meltzoff’s subjects re-enact the head action, when they could just have touched the light-switch with their hands?
The infants must have inferred that because the experimenter declined to use her hands despite the fact that they were free, the head action must offer some advantage in turning on the light.
The infants showed some kind of reasoning! Is it that the infants deliberate choose to imitate, rather than that they imitated involuntary
After watching the adult turn on the light with her head while her hands were free, the children also tended to switch on the light with their head (similar to what Meltzoff had found).
However,
after watching the adult turn on the light with her head when her hands were occupied (holding the blanket), the number of children who imitated the head action dropped significantly to only 21%. The majority used their hands.
argues imitation of goal driected action by preverbal infants is a selective interpretive process rather than a simple re-enactment
csibra 2007
proposes action mirroring is generated by action reconstruction via top down emulation from action interpretation produced outside the motor system. sych action mirroring does not follow but anticipates ongoing actions and enables, beyond predictive tracking, action coordination with others. he argues that the availabe empirical evidence is more compatible with this model than the direct matching account
meltzoff 1988
14 months old infants observe an adult switching on the light with her head.
1 week later, when they are shown the same light switch, they also switched on the light with their head.
= imitation (not emulation) of the unfamiliar head action.
saxe and kanwisher 2003
using tns found: The response (BOLD) in the TPJ-M is
High, when subjects read stories about another’s mental state
Low, when subjects read stories describing people in physical details or stories about non-human objects.
Thus, the authors claimed TPJ-M is specifically involved in reasoning about others’ mental states, and not just about other people.
dinstein 2010
show that individuals with autism exhibited not only normal fMRI responses in mirror system areas during observation and execution of hand movements but also exhibited typical movement-selective adaptation (repetition suppression) when observing or executing the same movement repeatedly.
Movement selectivity is a defining characteristic of neurons involved in movement perception, including mirror neurons, and, as such, these findings argue against a mirror system dysfunction in autism.
friedrich et al 2015
Mu Neurofeedback training to improve social functioning in autism
EEG rhythms can be influenced through feedback training (Kuhlman, 1978)
This method was further developed, and applied to the Mu rhythm and autism, by Pineda in San Diego
datko et al
positive effeccts of neurofeedback on autism symptoms correlate with brain activation during imitation and observation
heyes 2010
argues 3 advantages of the associative hypothesis of MN:
1) straightforward testable explanation of difference between monkeys and humans that have led some researchers to question the existence of the MNS
2) its consistent with emerging evidence that the MNS is involved with a range of social cognitive functions and domains but do not play a prominent specialised role in action understanding
3) supported by recent data showing that, even in adulthood, the MNS can be transormed by sensorimotor learning
associative account of MN
key figures: Bird and Heyes
implies that MNs comes from sensorimotor experience, and that much of this experience comes from interaction with others. Therefore if assoc account is correct, the MNS is a product, as well as a process of social interaction
`baron-cohen et al 2001
developed AQ and showed association between autism and scientists and mathemiticians (broken mirror hypothesis would not predict this strenth)
