The Evolution of Altruism And Its Relationship to Personality

Altruism, put simply, is helping others or cooperating with others, even if it is costly to self. Of course, something like that cannot evolve, unless there are benefits too, associated with such acts of apparent selflessness.

Evolutionary theory mandates that there be some genetic payoffs in terms of either inclusive fitness or future benefits to self (reciprocity) for any kind of altruism/ cooperation to evolve.

I recommend reading Wikipedia articles on reciprocity, kin selection, and evolution of cooperation if they are not familiar to you or you need a refresher.

Cooperation, to start with, can evolve based on three forms of reciprocity: direct, indirect and network. All are based on the fact that there re repeated interactions between group of people- dyads, triads or many more. Reciprocity can typically be measured in the lab using the repeated Dictator/ Trust game.

Direct reciprocity was proposed by Robert Trivers as a mechanism for the evolution of cooperation. If there are repeated encounters between the same two players in an evolutionary game in which each of them can choose either to “cooperate” or “defect”, then a strategy of mutual cooperation may be favoured even if it pays each player, in the short term, to defect when the other cooperates.

Here, in direct reciprocity A trusts/helps B and hopes that when time comes B will reciprocate/help A. The top-of-the-mind factor is whether or not to trust somebody and whether or not to reciprocate someone’s trust. Trust and exploitation may be relevant issues here. In the Dictator/ Trust game this trust/exploitation manifests as the amount that is split and given to the other person vs kept with oneself.

In the standard framework of indirect reciprocity, there are randomly chosen pairwise encounters between members of a population; the same two individuals need not meet again. One individual acts as donor, the other as recipient. The donor can decide whether or not to cooperate. The interaction is observed by a subset of the population who might inform others. Reputation allows evolution of cooperation by indirect reciprocity.

This is partially correct that reputation for being trustworthy helps in indirect reciprocity; however that is only true for the downstream version; for the upstream version feelings of gratitude/happiness/awe/elevation in persons receiving the help/ witnessing the act also lead to more pro-social behavior by those receiving help/ witnessing. Thus feelings of gratitude/ awe/elevation mediate this kind of upstream indirect reciprocity. See below for upstream and downstream variants.

Individual acts of indirect reciprocity may be classified as “upstream” or “downstream”:

  • Upstream reciprocity occurs when an act of altruism causes the recipient to perform a later act of altruism in the benefit of a third party. In other words: A helps B, which then motivates B to help C.

  • Downstream reciprocity occurs when the performer of an act of altruism is more likely to be the recipient of a later act of altruism. In other words: A helps B, making it more likely that C will later help A.

Before touching upon network reciprocity, I will take a quick detour about kin selection. I believe kin selection or inclusive fitness is also a type of reciprocity (that between related individuals sharing genes) and may be rechristened genetic reciprocity. After all if A is likely to help B because they share x % of genes, the reverse is equally true and applicable. And of course this is mediated by emotional attachment to the kid/kin.

As per one definition of kin selection:

A biological theory stating that a gene that causes an organism to exhibit behavior detrimental to its survival will increase in frequency in a population if that behavior benefits the organism’s relatives, which will pass the gene on to subsequent generations.

If I slightly change words form above definition, I can now define a neighbor selection process as a cultural theory stating that a meme that causes an organism to exhibit behavior detrimental to its survival will increase in frequency in a population if that behavior benefits the organism’s neighbors, which will pass the meme on to subsequent neighbors.

We are now ready to look at network reciprocity:

Real populations are not well mixed, but have spatial structures or social networks which imply that some individuals interact more often than others. One approach of capturing this effect is evolutionary graph theory, in which individuals occupy the vertices of a graph. The edges determine who interacts with whom. If a cooperator pays a cost, c, for each neighbor to receive a benefit, b, and defectors have no costs, and their neighbors receive no benefits, network reciprocity can favor cooperation.

Basically, what I understand from the above is that if you help your neighbors sometimes such that the cost is not too high but benefits to neighbors are high and if  cost to benefit compares favorably with average number of neighbors/ neighborly interactions you have, then in the long run you will benefit and this form of cooperation can evolve.  To me the effects are mediated by the number of neighbors or sociability of a person.

Of course, even if you have all these mechanisms in place, cooperation may not evolve, as you may have free-riders. One important mechanism that has evolved to keep the free-riders in check is that of punishment. And once punishment is part of the picture you don’t even need repeated interactions, one-off games may be sufficient. I call this phenomenon Direct Punishment. One way it has been measured is with the Ultimatum game.

In the Ultimatum game, the second player can inflict costly punishment on first player by refusing to accept the division; this costly punishment is dyadic in nature and the aggression/hostility/vengefulness of the second player ensures that cooperation in even one-off encounters happens.

Basically instead of trusting and helping B, A starts by exploiting B and B retaliates by punishing A at cost to oneself.

Of course one can then surmise that there can be a phenomena of indirect punishment. This again may happen in two ways:

  1. Indirect punishment upstream: A is exploitative in nature; A exploits B; B punishes A, who then feels guilt/ gets reformed and stops exploiting C or even starts helping C.
  2. Indirect punishment downstream: A is exploitative in nature: A exploits B, B punishes A; B gets a reputation for being tough/competent and stops getting exploited by others say C or C may now even help B.

The Indirect reciprocity effects can be seen in Public goods/ trust game.

I will now take a detour and introduce the HEXACO model of personality which set me thinking about this in the first place.

HEXACO is an alternate personality model that is based on the same principles as the Big Five/FFM; i.e. it uses factor analysis of lexical terms in various languages to arrive at major personality traits.

The six factors are generally named Honesty-Humility (H), Emotionality (E), Extraversion (X), Agreeableness (A), Conscientiousness (C), and Openness to Experience (O). The personality-descriptive adjectives that typically belong to these six groups are as follows:

  • Honesty-Humility (H): sincere, honest, faithful, loyal, modest/unassuming versus sly, deceitful, greedy, pretentious, hypocritical, boastful, pompous

  • Emotionality (E): emotional, oversensitive, sentimental, fearful, anxious, vulnerable versus brave, tough, independent, self-assured, stable

  • Extraversion (X): outgoing, lively, extraverted, sociable, talkative, cheerful, active versus shy, passive, withdrawn, introverted, quiet, reserved

  • Agreeableness (A): patient, tolerant, peaceful, mild, agreeable, lenient, gentle versus ill-tempered, quarrelsome, stubborn, choleric

  • Conscientiousness (C): organized, disciplined, diligent, careful, thorough, precise versus sloppy, negligent, reckless, lazy, irresponsible, absent-minded

  • Openness to Experience (O): intellectual, creative, unconventional, innovative, ironic versus shallow, unimaginative, conventional

The factor H is a new factor not present in Big Five/FFM. The E though looking similar to N of big Five, is conceptually different; it no longer contains anger/hostility which are instead present in HEXACO A. similalrly there are important differences between HEXACO A and Big Five A. the other 3, C, O and X (extarversion) are similarly conceptualized and defined in both systems and have same loadings when tested together.

Ashton and Lee, the proponents of the HEXACO model, have themselves related evolution of altruism to these traits [pdf] and I am building on their work.

Basically as per them,

To begin, we have proposed that the Honesty- Humility and Agreeableness factors represent two complementary aspects of the construct of reciprocal altruism (Trivers, 1971). Honesty-Humility represents the tendency to be fair and genuine in dealing with others, in the sense of cooperating with others even when one might exploit them without suffering retaliation. Agreeableness represents the tendency to be forgiving and tolerant of others, in the sense of cooperating with others even when one might be suffering exploitation by them. (For a discussion of two broadly similar, although not identical, constructs, see Perugini, Gallucci, Presaghi, & Ercolani, 2003.) Presumably, high levels of Honesty- Humility are associated with decreased opportunities for personal gains from the exploitation of others but also with decreased risks of losses from withdrawal of cooperation by others. In a similar manner, high levels of Agreeableness are associated with increased opportunities for personal gains from long-run reciprocal cooperation with others, as well as with increased risks of losses from exploitation by others. (Note that we use the term altruism in terms of a dimension of altruistic versus antagonistic tendency, which involves both a willingness to help or provide benefits to others and an unwillingness to harm or impose costs on others.)
In addition, we have proposed that Emotionality represents tendencies relevant to the construct of kin altruism (Hamilton, 1964), including not only empathic concern and emotional attachment toward close others (who tend to be one’s kin) but also the harm-avoidant and help-seeking behaviors that are associated with investment in kin (see also Lee & Ashton, 2004). Presumably, high levels of Emotionality are associated with increased likelihood of personal and kin survival, as well as with decreased opportunities for gains that are often associated with risks to personal and kin survival.
To me, this looks like equating direct reciprocity with H and direct punishment with A.  With this in mind I now list the personality trait (HEXACO)/ evolution of altruism linkages.
1. Kin Selection/ Genetic Reciprocity : mediated by emotional attachments etc and related to Emotioanlity.
2. Neighbor Selection / Network Reciprocity: mediated by sociability and related to sociability aspects of Extrarversion.
3. Direct Reciprocity : mediated by trusting others and being honest and related to Honesty-humility.
4. Direct Punishment:  mediated by punishing others and being aggressive/ hostile when needed and related to Agreeablness.
5. Indirect Reciprocity upstream:  mediated by feelings of gratitude/ awe/ elevation and possibly related to Openness to Experience
6. Indirect Punishment upstream: mediated by feelings of guilt/responsibility and related to Conscientiousness.
 7. Indirect Reciprocity downstream: mediated by signaling and being trustworthy; need a new personality dimension for this.
8. Indirect Punishment downstream: mediated by signaling and being competent/ tough and possibly related to Surgency dimension of Extarversion.
I am more and more convinced, looking at the above model that we evolved to be cooperative/ altruistic rather than otherwise.

Altruism as a result of sexual selection

First published in Fun, Nov 1872. Original cap...
Image via Wikipedia

There is a new article in BPS, that has found some evidence for the fact that altruism may have evolved by the process of sexual selection.

There are many mechanisms that underlie exactly how and why sexual selection takes place- one is the ‘handicap’ /’costly honest signal‘ theory according to which a trait that is actually disadvantageous or a handicap for the host evolves to signal exactly that fact- that despite this handicap I am able to function well and must therefore be of better genetic quality; the most common example being the evolution of peacocks tail which is a handicap and makes the male peacock carrying a big tail more vulnerable for predation, but also is attractive to females and preferred by them.  Another theory is that of ‘runaway selection’ i.e . a trait may evolve in a direction due to some genetic drift and the preference for it may also evolve in tandem such that there is  a slight leaning or preference towards that trait. Now, in a competition, those, typically males, who have that trait will be selected by the females and their progeny will have an advantage as they are more likely to display that trait and be favored by subsequent generations; thus an arbitrary trait may get fixed by this runaway selection where all members of the species want to be part of the new fashion/club in town. I know I am drawing very loose analogy, but just to give an idea. Nakedness or loss of hairs in humans is predicted to have followed this pattern.

Of course sexual selection also differs on whether it is largely intrasexual, driven by competition (selection pressure) between males for eg  having big antlers to defeat and subjugate another male; or is driven by mate preferences and has intersexual selection dynamics- like the peacocks tail.

What the authors of this paper hypothesized was that sexual selection is behind the evolution of altruism or selfless concern with non-kin and that this being the case and this sexual selection dynamics being driven by inetrsexual dynamics, there are bound to be genetic underpinnings to both the trait altruism as measured in males/females and the mate preferences for altruistic trait in both females as well as males. The reason they didn’t anticipate any differences in male sand females was that parental investment, as per them, is roughly equal in case of humans and so both males and females exert equally strong sexual selection pressure son each others traits and ‘choose’ their mates equally.

However, in this study they looked only at females and their genetic basis for altruistic traits as well as mate preference for altruism. The altruistic traits and mate preferential weer measured using self-report instruments.  the genetic components underlying these were estimated using classical twin studies paradigm where correlation between mono-zygotic twins and di-zygotic twins are compared to estimate the genetic contribution. They also calculated the phenotypic correlation between mate preference for altruism and altruistic trait in individuals and tried to calculate how much of this correlation again was genetic in nature or in other words was a result of  mating between those who had the trait and those who preferred the trait. . They hypothesized that in the ancestral environmental this type of mating for trait altruism would have taken place and thus these would be genetically correlated.

This is exactly what they found; they found that both altruistic personality and mate preference for altruism had genetic components and that they both co-varied and that covariance again had genetic component.  the pare itself is full text open access and is written very well, so go ahead and read it yourself. this is an important paper that has come timely when the whole kin-selection paradigm for evolution of eusociallity is being challenged by E o Wilson and team and provides a fresh and alternative perspective of why altruism may have evolved.

Here is a tit-bit from the discussion:

We believe that the sexual selection hypothesis for the evolution of human altruistic traits should now be considered alongside other more established theory (Bshary & Bergmu¨ller, 2008; Lehmann & Keller, 2006), particularly as there is the possibility that multiple mechanisms might underlie a complex behaviour such as altruism. Empirical testing of contrasting theories might even be possible. For example, reciprocal altruism (Trivers, 1971) does not strictly predict the genetic correlation between MPAT and ‘altruistic personality’ found here as ongoing reciprocation towards others would not necessarily result in such a selective process. Indirect reciprocity (Leimar & Hammerstein, 2001) concerns reputation directed towards all other group members while the sexual selection hypothesis focuses solely on altruistic displays that can be evaluated by potential mates (Phillips et al., 2008). A study that examined ‘costly signalling’ of altruistic behaviour through personal donation to a children’s charity found a significant effect on male behaviour when witnessed by a female observer while no such effect was found when male participants were observed by same sex others (Iredale et al., 2008), a finding that could be seen to be at odds with indirect reciprocity. Additional studies could further elucidate the effects of altruistic reputation when directed towards same sex others as opposed to potential mates, thus testing the relative claims of indirect reciprocity against the sexual selection hypothesis.

Tim Phillips1, Eamonn Ferguson2, & Fruhling Rijsdijk (2010). A link between altruism and sexual selection: Genetic influence on altruistic behaviour and mate preference towards it British Journal of Psychology DOI: 10.1348/000712610X493494

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The Varieties of Altruistic Experiences

Altruism is a very heavily loaded word  in evolutionary psychology/ biology and I would not add to the confusion by defining the term myself. Suffice it to say , that I will use it in all of its various intuitive and theoretical usages.

The evolution of biological Altruism is generally considered as a challenge to Darwinian evolution and there are thought to be two main theories of how Altruism is possible or has evolved. These are Hamilton’s Kin-selection and inclusive fitness theory and Trivers’ Reciprocal Altruism theory, though some prominent people disagree that there are indeed two separate phenomenon at work and try to argue that they are one and the same phenomenon

I would argue instead that there are more varieties of Altruism than the above two- and that it may also be beneficial to decompose the phenomenon of kin selection and reciprocal altruism into their sub components and to to derive/ elucidate the proximate mechanisms that are involved in these phenomenon as opposed to a single-minded focus on the ultimate explanations of why and how such models can give rise to altruism.

To that effect I would like to separate the parental-investment and parent-child ‘kid-selection’ effects from other genetic relatives or ‘kin-selection’ effects. The reason I believe they are separate is because having a child or Kid involves bringing in a new relative with 0.5 relatedness in this world , so the cost to bring in to the parent can be very high as post facto (childbirth) the inclusive fitness becomes 1.5 +0.5b-c (cost) while earlier it was only 1.  Thus, the act can be undertaken if 0.5 +0.5b>c.  In the kin selection case however the inclusive fitness is 1-c +0.5+ 0.5*b after the altruistic act vis-a-vis 1.5 before the act ; so  the act can only be undertaken if 0.5b>c . the addition of a constant 0.5 to the first equation changes the dynamics to a large extent and thus my idea to keep the two phenomenon separate.

Also, reciprocal altruism can itself be broken into some differing phenomenons. The first phenomenon is generalized reciprocity (which is even found in rats , see also this) and others are direct, indirect and strong reciprocity. To summarize form an earlier post:

As per what is know about the evolution of Altruism, it is surmised that co-operation in groups emerges based on four types of reciprocity- direct, indirect, strong and generalized.

In direct reciprocity, one helps another person/animal because the other animal has helped oneself in the past. This requires cognitive capacities to recognize different individuals and require social memory as to which member of the group had helped and which had defected or free loafed. While some animals like the Elephant have good social memories and the ability to remember and recognize different individuals, most animals fall short on these traits.

In indirect reciprocity, one helps another because one has observed the other guy to have helped someone else. This again requires cognitive capacities to recognize and also to remember This is more so based on a reputation system, wherein you start trusting someone more if you observe him doing good deeds. In return you are likely to help the do-gooder , when he is in time of need.

In strong reciprocity, people punish the defectors or free-loafers or non-cooperators. This requires sophisticated cognitive abilities to recognize the defectors and a willingness to undergo cost to oneself while punishing the defector. This too, along with the above two, has rarely been observed in animals apart from humans.

Finally, generalized reciprocity happens when one indulges in good deeds towards a stranger just based on the fact that one has in the near future received such help from other strangers/ con specifics. There are variations on this theme, whereby if people have been put in a good mood (which is a substitute for having received a good deed) they are more likely to indulge in altruistic acts like picking up books dropped by a confederate. This type of reciprocity does not make very strong cognitive demands as one just has to remember the summary of whether the environment is cooperative or not, to produce the right kind of behavior.

So based on above I would like to differentiate between two clusters of reciprocity: Generalized reciprocity not requiring sophisticated cognitive mechanisms, but requiring global assumptions about the social environment; and strong, direct and indirect reciprocity – all involving sophisticated cognitive mechanisms but not dependent on assumptions about the global social environment.

With this I would now like to move to my main thesis. I argue that altruism is a social and group phenomenon and to understand all the proximal mechanisms that are involved in altruistic acts we have to appreciate the mechanisms and drives that lead to group formation, group cohesion and expansion and finally group thriving or differential success from other similar groups based on selection of members belonging to the group such that their is non-zero sum benefits of being in the group.

I would argue that all of the above can be understood in the eight stage framework, with the first three stages related to group formation; the next two related to investment in group (expanding or making it cohesive) and the last three related to populating the group with better individuals/ creating a suitable group that has maximum payoffs for all.

To start with , let us revisit the eight basic adaptive problems as elaborated here and here.

  1. The first problem to be solved ‘foe’ is also the first primary driver for the evolution of groups. Groups or herd evolve per se, because a solitary creature is more vulnerable to predation than as part of a group. This is how herding evolved. The proximate mechanism working at this level is that of merging with a group. 
  2. The second problem to be solved ‘food’ is the secondary driver for evolution of groups. It is envisaged that hunting/ gathering as part of a group leads to better  and bigger catches than are individually possible. this provides the incentive to work with other group members to hunt/ forage. This introduces the problem of who would eat the catch when one of them kills, but others are part of the raid party. The solution to the above problem is achieved using the mechanisms of sharing of the spoils. Thus, the proximate mechanism working at this level is a tendency to share the food / resources when begged for by those who are of the same band/ herd/ raiding party.  
  3. The third problem to be solved is ‘friends’ or con-specifics themselves. As all the group members  are competitors in the same niche, they have to learn to form alliances and co-operate in non-zero sum games with other partners when such co-operation does not entail a price and leads to mutual benefit.the example here would be that of grooming. A bird cannot remove lice from the top of its own head , but can do so easily if another friend removes the lice for her. This is a nonzero sum game. by co-operating both gain and nobody loses. The grooming can happen simultaneously so there is no reciprocity or memory involved. The proximate mechanism here is that of grooming or befriending (spending time with other just to make the alliance better).
  4. The fourth problem to be solved is that of ‘kids‘ and how to help those vulnerable, but related individuals. The kid-selection and parental investment concerns dominate here and lead to emergence of altruism directed towards ones offspring. Now the proximate mechanism devised to help in kid selection is that of care or empathy and this extends to all those who are sick,  vulnerable, infirm or unable to fend for themselves. The care ethic is born and is most visible in contexts where the mother-child or provider-infirm relationship can be activated. Help in rearing infants by related aunts etc is an example of this mechanisms.
  5. The fifth problem to be solved is that of ‘kin’ or all the other related individuals in the group. Kin selection comes into picture, but for it to work one has to properly identify ‘like’ people, who are likely to share genes. It is presumed that selection favored those who can judge likeness of phenotype from likeness of genotype and a a simplistic scenario could be that all the group members are considered as like and one tries to identify with them. This is as opposed to trying to differentiate from them and treating them as not-like. Thus, the proximate mechanism involved could be that of loyalty to the group and identification with the group as opposed to rebelliousness/ unconventionality/ differentiation from the group. The drive to find ‘like’ and ‘related’ individuals could easily lead to the ethic of community/ loyalty towards the self identified group. Also, forgiveness instinct towards those considered part of group and hence pertaining to valuable relationships that should be maintained despite small annoyances.
  6. The sixth problem to be solved is that of ‘selecting’ a partner/ partners with which one could indulge in altruistic games. Here the payoff to another would be at a cost to oneself and hence it is not a simple case of co-operation or mutualism in which both parties would benefit. Ideally, when partners have not been determined a priori and one has to discover the characteristics of the majority of the partners (or the population)  and at the same time not harm oneself by unconditional altruistic costs, the viable strategy would be to play with many diverse individuals and play using a generalized reciprocity scheme. At the end of many iterations, one can look at ones strategy and depending on how much altruistic or selfish it is, determine the characteristics of the population. This requires minimal cognitive demands as in not requiring the ability to remember individual interactions. In simple words this can be dubbed as Trust. You trust other people as you do not really know them, except in so far as they are part of the group and hence likely to have a majority group characteristic.  thus, a typical example would be ultimatum game. though the person with which you may playing may be stranger, you know a few things from your generalized reciprocity interactions with other individuals to know that majority of them are fair (make offers at 50 %) and also punish small splits. Thus, based on how you yourself have been given endowments in the past (and how others have rejected endowments given by you) you can reasonably play an ultimatum game with a stranger with same population wide results. Thus, the proximate mechanism here is that of Trusting others to be like the general population stereotype. thus, in humans, most of us are ‘altruistic’/ ‘good’ and hence we trust well rather than be suspicious.             
  7. The seventh task is that of seducing or attracting the right kind of partners so that the payoff the group, and hence yours, increases. Three separate mechanisms are at work here. Direct reciprocity harnesses our ability to remember individuals to pay them back in the future. Gratitude is the proximal mechanism that ensures that we do indeed pay back when time comes. Strong reciprocity ensures that we pay back, in another sense of the term, to the free-riders / defectors. By having punishment in the system one can ensure that the group is not overtaken by free-riders and defectors. The proximal mechanism active here is that of vengeance and not letting the culprits go off scot free. Indirect reciprocity on the other hand works on third party interactions and is based on respect , that is a generalized reputation of an agent to be ‘good’/’bad’ and acting towards them based on their reputations rather than their immediate behaviors. The proximate mechanism active here is respect/ authority. 
  8. The eighth task is to secure the group or keep the group well-knit and isolate form other ‘corrosive’ groups. One problem that poses a hurdle to group securing is unexpected payoffs (like war loot) and how they are handled by the group. They may be distributed to everyone equally, distributed as per a hierarchy or consumed by a few dominant individuals.Here the ethics of fairness and equality is the proximate mechanism that is used to settle matters. Another important factor here is not to let other group members infiltrate the successful group and subvert it from within. This gives rise to the ethic of purity and sanctity : the group is considered pure and sanctimonious and only other pure individual are allowed to join the group. The perverts within the group may be destroyed/ redeemed/ salvaged.                     

Thus, in my view, altruism involves all these proximal mechanisms: merging, sharing, grooming and befriending, caring, loyalty (identifying and forgiving), trusting; justice as in gratitude (positive justice),vengeance (negative justice) and respect (generalized justice); and finally the ethics of fairness/equality and purity /sanctity. Some of these can be easily mapped to Haidt’s five basic moral foundations.

In a follow-up post I will try to show how these eight altruistic proximate mechanism are reflected in personality traits especially with reference to HEXACO personality model to which one of my readers pointed me to.

Autism / Psychosis: Agency and Joint Attention

A recent study by Tomosello’s group indicates that children with autism, can help a stranger pick a pen (and thus can apparently infer goal and intentional states of others), but cannot indulge in co-operative behavior that may involve shared goals and shared attention.

As per Translating Autism blog:

This fresh-off-the-press article comes to us from Dr. Michael Tomasello’s group at the Max Planck institute in Germany. The authors present the results of two studies looking at helping and cooperation in children with autism. The first study compared 15 children with ASD (14 with Autism and 1 with PDD-NOS) with 15 children with other non-ASD developmental delays (40 months of age average). During this study the children were place in situations that either called for helping behaviors (such as picking up a pen that the researcher dropped and could not reach) or a similar situation that did not necessarily call for helping behaviors (such as when the researcher threw the pen on purpose and did not attempt to pick it up). Both groups (children with Autism and children with other developmental delays) showed more helping behaviors when placed in the situation that called for such behaviors. That is, when the experimenter was “trying” to reach an out-of-reach object, both groups were more likely to help than when the experimenter was not trying to reach for the object. The authors concluded that these behaviors showed that both groups understood the adult’s goals and were motivated to help her. In the second study, the same children were placed in situations that called for “cooperative” behaviors, such as a task requiring them to work with the researcher by simultaneously pulling at two cylinders to reach a toy. The results showed that children with autism were less likely than kids with other developmental delays to successfully complete the cooperation tasks. Furthermore, the children with autism were less likely to initiate additional attempts to complete the task when the task was interrupted. The authors concluded that, at least at this developmental period, children with autism seem to understand the social components of situations that call for “helping” behaviors and engage in helping behaviors, but only when such help does not require interpersonal cooperation. However, when cooperation is required to complete the task, these children are less likely to correctly engage with another partner, possibly because the unique “shared” component of cooperation. That is, cooperation requires shared goals, shared attention, and a shared plan of action, processes that seem to be affected in children with autism.

Here is the abstract of the Tomosello paper:

Helping and cooperation are central to human social life. Here, we report two studies investigating these social behaviors in children with autism and children with developmental delay. In the first study, both groups of children helped the experimenter attain her goals. In the second study, both groups of children cooperated with an adult, but fewer children with autism performed the tasks successfully. When the adult stopped interacting at a certain moment, children with autism produced fewer attempts to re-engage her, possibly indicating that they had not formed a shared goal/shared intentions with her. These results are discussed in terms of the prerequisite cognitive and motivational skills and propensities underlying social behavior

From the above it is clear that children with Autism lack shared attention: a pre-requisite for language and their language impediments may also be due to this fact. If we contrast this with Schizophrenia/ Psychosis ( and assuming they are at opposite ends) it is not hard to see that with too much shared goals/ intentions/ attention, one may likely confuse between one’s own goals and those of others and in a joint scenario be more susceptible to delusions of control/ though insertion, wherein the shared space has become so vast that one seems to be controlled by the other or intruded by the other. thus , I propose that children susceptible to psychosis should show enhanced cooperating behavior indicating an overactive shared goals/ attention module.

Another interesting study I would like to discuss is the recent reporting of a dysfunctional ‘self’ module/model in a Trust game as compared to the ‘other’ module/ model. Here is how the Science Daily describes the Trust game that was used in the game.

In the trust game, one player receives an amount of money and then sends whatever amount he or she wants to the other player via computer message. The amount sent is tripled and the player at the other end then decides how much of the tripled amount to send back. The game has several rounds.

The ‘self’ module was identified as the brain areas (cingulate cortex) involved when making the decision to share the initial amount of money with another person. The ‘other’ module was defined as network region activated when the decision of the other player was revealed to them.

It was found that autistics showed lowered activity in the ‘self’ module. The authors construe this as evidence that they have a defective self concept.

“To have a good self concept, you have to be able to decide if the shared outcome is due to the other person or due to you,” said Montague. “If people can’t see themselves as a distinct entities at deeper levels, there is a disconnect.”

I beg to differ. In my view the findings can be explained using the joint attention / goal/ outcome defect outlined above. Although I believe that their explanation that people with autism may have a diminished sense of self or Agency also makes intuitive sense and I have argued the same previously. I contrast that with the Psychotic case where one attributes too much agency- even to inanimate objects or animals for example. However, in this case a more parsimonious explanation can be that the autistics were not able to model the others goal as their own (the familiar simulation argument) and could not indulged in joint goal intention and thus failed to optimally use the ‘self’ module i/e failed to take whatever actions were needed for a co-operative and trustful behavior .

The Friths adequately sum that up:

In a preview in the journal Neuron, Chris and Uta Frith wrote, “This is an exciting result because it suggests that some mechanisms of social interaction are intact in these high-functioning cases. What is the critical difference between the self phase and the other phase? We believe that the simple distinction of self versus other is not adequate. “It involves higher-order mentalizing: you care what another person thinks of you, and even further, you care that the other person trusts you. You would not do this when playing against a computer. In autism there is no difference,” wrote the Friths, who are at University College London.

Neural correlates of trust

This is the title of a new paper in PNAS by Krueger et al, that tries to find the neural correlates of conditional and unconditional trust using the sequential, reciprocal trust game. The authors premise is that conditional trust is more costly strategy compared to unconditional trust and might utilize different brain areas as well.

Conditional trust assumes that one’s partner is self-interested and estimates the expected value of one’s strategy with respect to the benefits of cooperating, the risk of defection, and the future value of past decisions; it causes less balanced goodwill and results in greater variance in cooperative decisions and, therefore, is cognitively more costly to maintain. In contrast, unconditional trust assumes that one’s partner is trustworthy and updates the value of one’s partner with respect to their characteristics and past performance; balanced goodwill occurs more quickly, allowing the partners to attain high levels of synchronicity in their decisions and, therefore, is cognitively less costly to maintain. In this work, an examination of functional brain activity supports the hypothesis that the preferential activation of different neuronal systems implements these two trust strategies.

The results of their experiments supported their initial hypothesis and they found that while Para Cingulate cortex (PcC) activation was necessary for menatlizing and initial building of trust; later unconditional and conditional trust strategies deployed different brain areas viz Septal Area (SA) and Ventral Tegmental Area (VTA) respectively.

Unconditional trust assumes that one’s partner is trustworthy. During the building stage, first movers in the nondefector group showed higher activation in the PcC compared with first movers in the defector group. Through mentalizing, partners of this group verified their prior trustworthy assumption, updated the value of one’s partner’s strategy with respect to their past performance, and maintained a balanced goodwill toward each other, allowing them to avoid defections. By developing “better” mental models in this early stage, partners in the nondefector group accumulated sufficient mutual goodwill to become socially attached to each other and adopted an unconditional trust strategy.

During the maintenance stage, the nondefector group showed a higher activation in the SA compared with the defector group. Across groups, pairs who showed the highest trust-reciprocate history in their decisions also showed the highest activation in this region. Furthermore, analyses of pre- and postscan behavioral ratings confirmed that only nondefector pairs felt significantly closer to each other and ranked themselves as being more of a partner to the other person after the experiment. Through early mentalizing, partners in the nondefector group must have balanced goodwill more quickly, allowing them to become synchronized in their decision patterns. Brain-to-brain correlations only increased in the SA region for the nondefector group across stages, and only partners in the nondefector group became synchronized in their SA BOLD amplitudes as first movers in adjacent trials of trust games. Synchronization in the SA led to social attachment associated with a significant decrease in activation in the PcC during the maintenance stage. By adopting this cognitively less costly strategy, decision times became significantly faster for the nondefector group across stages of the experiment.

Conditional trust assumes that one’s partner is self-interested. During the building stage, first movers in the defector group showed less activation in the PcC compared with the nondefector group. Through less mentalizing in the building stage, partners in this group produced higher errors in the inferences of second movers’ goodwill toward them, resulting in less balanced goodwill and, therefore, in less overall trust compared with the nondefector group. More importantly, they started to trust more in the low-payoff games and less in the high-payoff games. This decision pattern implies that defectors were adapting a conditional trust strategy by evaluating the expected value of one’s strategy with respect to the risks and benefits of cooperation.

During the maintenance stage, the defector group showed higher activations in the VTA compared with the nondefector group, a region linked to the dopaminergic mesolimbic reward system providing a general reinforcement mechanism to encode expected and realized reward . Across groups, pairs who shared the lowest trust-reciprocate history in their decisions also showed the highest activation in this region. By adopting a cognitively more costly strategy, partners in the defector group showed a significant increase in activation in the PcC over the experiment. Through more mentalizing in this late stage, first movers in the defector group tried to develop more accurate models about the likelihood of their partner’s choices so that they could make a more advantageous decision about when to trust. The conditional trust strategy paid off less over time as total earnings decreased for the defector group (but increased for the nondefector group) across stages.

Thus, it seems that SA, based on oxytocin and vasopressin and social bonding is a more cost-effective strategy than the VTA based on dompainerigic system based on reward monitoring.

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