Evolutionary Psychology Lecture 12: Theory of Mind (ToM).

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Evolutionary Psychology Lecture 12 Theory of
Mind (ToM).
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Learning Outcomes.

• At the end of this session you should be able to
  
• 1. Evaluate the evidence concerning the existence
  of self-awareness and theory of mind in
  animals.
• 2. Discuss evolutionary explanations for the
  development of theory of mind in humans.

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Intentional Understanding

• Humans display an automatic and pervasive set of
  behaviours that revolve around the interpretation
  of the behaviour of the self and others in terms
  of inferences about unobservable mental states.
• Humans assume that other people are intentional
  agents who possess a mind very similar to our
  own, we treat them as having mental states
  opinions, thoughts, fears, emotions, beliefs,
  intentions (Povinelli Preuss, 1995).
• We are skilled at predicting other peoples
  intentions, spotting a liar or cheater, realising
  that someone is unhappy or afraid etc.

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Theory of Mind (ToM).

• We therefore possess the ability to understand
  and act upon the fact that other individuals
  possess a mental state which may differ to that
  of ourselves.
• These mental states are
• 1. Independent of the real world (we can all
  believe things that are not true).
• 2. Independent of the mental states other people
  may have (we all believe, desire and pretend
  different things from one another).
• This mind reading ability is referred to as
  Theory of Mind (ToM) and was originally
  proposed by Premack Woodruff (1978).

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How Important is a ToM?

• Baron-Cohen (1999) pointed out the importance of
  a ToM and lists a series of behaviours that
  depend upon it
• Intentional communication with others.
• Repairing failed communication with others.
• Teaching others.
• Intentionally persuading others.
• Intentionally deceiving others.
• Building shared plans and goals.
• Intentionally sharing a focus or topic of
  attention.
• Pretending.
• Such behaviours are consistently impaired in
  autism and as yet, there is no clear evidence
  that they are consistently seen in our close
  relatives (monkeys and apes).

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The Development of ToM.

• Barresi Moore (1996) summarised the development
  of the understanding of intentional relations in
  humans
• 2 months Infants become interested in social
  stimulation and can engage in social interactions
  (e.g smiling).
• 4-5 months they pay attention to non-social
  objects but do not coordinate person-directed
  behaviour and object-directed behaviour.
• 12-18 months Engage in proto-declarative
  pointing (drawing the attention of someone else
  to an object by pointing at it) and can track
  another persons line of gaze.
• These behaviours indicates that the infant is
  developing a concept of another person as an
  'intentional agent'.

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The Development of ToM (continued).

• 18-24 months The emergence of conceptual
  knowledge of the self emerges and we see the
  following
• Recognition of self in mirrors.
• Symbolic play.
• Simple acts of altruism (giving a toy to another
  child).
• Reciprocal co-operation with others (sharing,
  simple co-operative play).
• Linguistic comments about the failure or success
  of self-generated plans.
• Mastery smiles upon the completion of a task.
• Use of mental state terminology to refer to
  desires.

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Understanding of False-Belief

• Between the ages of 3-5 children understand that
  beliefs are individual mental representations.
• They also understand that someone else may hold a
  belief that differs to their own.
• This ability can be demonstrated using
  false-belief tests such as the 'Sally-Anne test'
  (Wimmer Perner, 1983).
• Baron-Cohen et al., (1985) tested 20 autistic
  children on this task and found that 80 failed
  to appreciate Sallys false belief and said she
  would look in the box.
• In contrast, normal children, children with
  language impairments, and children with Downs
  syndrome succeed on this task.

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The Sally-Ann Test.
From Happé, 1994, p41
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The Evolution of ToM.

• A key question concerns whether ToM has only
  evolved in humans, or whether ToM evolved before
  the divergence of humans.
• If the latter is the case then we would also
  expect to see ToM capabilities in our near
  relatives.
• According to Humphrey (1978), self-knowledge, and
  through it the intuitive knowledge of others,
  have made an essential contribution to the
  reproductive fitness of social animals.
• In complex social groups the ability to
  understand and predict another individuals
  behaviour would be an enormous advantage.
• This complicated skill would require superior
  intelligence (as seen in social animals) and both
  would evolve through natural selection.

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Self-Consciousness.

• Dennett (1996) argued that self consciousness can
  be seen as a hierarchy of intentional systems
• First order having beliefs and desires about
  many things, but not about beliefs and desires
  (most animals, human infants, autistic
  individuals?).
• Second-order having beliefs and desires about
  beliefs and desires, of self and others (humans,
  other primates?).
• Third-order having the capability of such feats
  as wanting another individual to believe that you
  want something (humans, other primates?).
• Fourth-order having the capability to make
  another individual believe you want it to believe
  that you believe something (humans only?).

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2nd Order Understanding.

• The giant leap of being able to generalise about
  other individuals comes between stages 1 and 2.
• An interesting question is How did some social
  animals make this leap?.
• Dennett (1996) points out that a likely candidate
  is communication, and especially in humans the
  emergence of language.
• Communication enables social competition,
  exchange, alliance building, transmission of
  important information, culture, and deception.
• Language was invented so that people could
  conceal their thoughts from one another
• (Charles-Maurice de Talleyrand).

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Baron-Cohen, (1999).

• Unlike Dennett, he believes that a ToM must have
  preceded language, as without ToM being able to
  speak or perceive speech would have been of
  little value.
• For example, autistic children possess language,
  it consists of syntax, vocabulary and semantics,
  but lacks pragmatics - the ability to decipher
  someone's intentions from their speech.
• He further argues that ToM certainly existed
  around 40,000 years ago and it must have been
  present around 100-150,000 years ago during the
  dispersal from Africa, but before then there is
  little firm evidence of its existence.
• He argues that apes clearly show social
  intelligence but this does not necessarily mean
  that they possess a ToM.

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Deception.

• Much of social life is concerned with hiding our
  true intentions.
• A complex social environment led to the need for
  deception, which led to increased social
  intelligence, which led to language and symbols,
  which led to higher-order self-awareness and an
  advanced theory of mind.
• Machiavelli was a Florentine diplomat whose name
  has become synonymous with a strategy of social
  conduct in which others are regarded entirely as
  a means towards a personal end.
• Human social intelligence may have evolved in
  order to understand, predict and manipulate the
  behaviour of other people.

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Psychological Qualities of Machiavellianism.

• Individuals scoring highly on Machiavellian
  traits are called High-Machs and according to
  Wilson et al., (1996) display the following
• Are perceived as being more intelligent, socially
  attractive, and charming.
• Take centre-stage and adopt leadership roles.
• Easily beat 'low-Machs' in bargaining and
  alliance-forming situations.
• Are more likely to use exploitative and
  manipulative tactics in group situations, and are
  more successful in short-term, face-to-face
  interactions.
• Are less likely to empathise with others, or help
  others in an emergency.
• Are more believable liars, maintain greater eye
  contact and confess less often.

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Somatic Marker Mechanism.

• Damasio (1995) referred to the neural mechanism
  for TOM as the somatic marker mechanism (SMM).
• This involves the use of ones emotional
  reactions as indicators of another persons
  mental state.
• E.g if the approach of a stranger induces an
  emotional response of fear, a combined
  emotional-perceptual representation of hostile
  stranger is created in working memory.
• If at a later date these perceptual
  representations are reactivated from memory, the
  linked emotion of fear will also be deployed.

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Do all Humans Possess a ToM?

• Individuals who lack a ToM will be fundamentally
  disadvantaged in social situations as they will
  be unable to predict the intentions of others.
• In some people the ToM mechanism is either absent
  or dysfunctional (autistics) and they show
• Lack of awareness of the existence or feelings of
  others.
• Lack of social, imaginative play, they mainly
  play alone.
• Gross impairment in the ability to make friends.
• They do not understand jokes.
• Abnormal non-verbal and verbal communication.
• Impairment in initiating and sustaining
  conversation.
• They follow routines rigidly and hate change.
• Restricted and obsessive range of interests
  usually object based.

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Evidence for ToM in Primates.

• 1. Self-Awareness.
• If presented with a mirror, most animals (and
  human children below 2) react as if confronted by
  another animal.
• Even if exposed to the experience of seeing a
  mirror on a regular basis, most animals never
  show evidence of self recognition.
• Chimpanzees and orang-utans can learn that the
  reflections are representations of themselves, as
  they use the mirror to inspect parts of their
  bodies that they cannot see.
• Gallup (1998) argued that animals who possess
  self-awareness can use such experiences to model
  the experience of others (empathy).

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Self-Awareness?
From Gallup, 1998, p 70
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2. Empathy.

• Povinelli (1992) devised a task in which one
  human could see which of two handles would give
  food rewards when pulled, but could not reach the
  handles.
• To succeed, the individual has to indicate the
  correct choice to a second individual, who can
  reach the handles but who cannot see which one is
  correct.
• Chimpanzees but not rhesus monkeys could learn
  either role, and switched roles as necessary.
• Povinelli et al., (1994) allowed a chimpanzee to
  choose the advice of one of two human helpers in
  deciding which container is baited with food.
• Only one human saw the baiting, and chimpanzees
  accurately selected the human who had seen the
  baiting as their helper.

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Povinelli et al., (1994) Study.
From Byrne, 1995, p108
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Alternative Explanations.

• Povinelli et al., (1998) provided chimpanzees
  with a choice of someone who could see them and
  someone who could not.
• The animals behaved in a random manner, sometimes
  selecting the sighted helper, but other times
  selecting the unsighted helper.
• In another experiment the experimenters sat with
  their backs to the chimpanzee, but one looked
  over her shoulder at them.
• Again performance was random.
• They also found that chimpanzees may not
  comprehend pointing gestures as referential
  actions.

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Alternative Explanations (continued).

• Povinelli (1998) also provided an explanation for
  chimpanzee success in mirror tasks.
• He argued that success is based on recognition of
  self-behaviour, ie when chimps see themselves in
  the mirror they form an equivalence relation
  between the actions they see and their own
  behaviour.
• They conclude that everything that is true for
  the mirror is also true for their own bodies and
  vice versa thus they can correlate coloured
  marks on the mirror image with marks on their own
  bodies.
• They dont conclude thats me!, rather they
  conclude thats the same as me.