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matt j rosano
Matt J Rosano
Southeastern Louisiana University

Matt J. Rossano received his doctorate in Psychology from the University of California at Riverside in 1991. He is a Professor of Psychology at Southeastern Louisiana University in Hammond, LA. He is the author of Supernatural Selection: How Religion Evolved, released in June 2010 by Oxford Press. His interests include: Evolution and human nature, evolutionary psychology, consciousness, evolution of the mind/brain, religion and science, and evolution of religion.


Around 100,000  years before present(ybp), anatomically modern humans (AMH)(these are not the same as Neanderthals and other hominids at the time) went back to the place from whence they emigrated, Africa; however, their retreat did not last as they were expanding again into the Eurasian landmass again 60,000 ybp and showing evidence of a much more sophisticated social structure and developed levels of cognition. This might have been due to ecological conditions in Africa at the time that created an extinction environment for AMH. From this, a level of social complexity partly based in religion emerged.tobatoba

According to Stanley Ambrose, a professor at the University of Illinois, during this period of difficulty for AMH, there was an eruption that caused a 6-10 year volcanic winter followed by a 1000 year winter winter(an ice age). This served to bottleneck AMH’s population to about only 2000 individuals, which luckily is the closest humans have ever come to extinction. This problem set the stage for a series of developments for human cognition’s development into what it is today.

The Social Solution

Around 75,000 ybp, we see evidence of trade going on around Africa: stashes of beads and sets of tools are found together, and we know they have intrinsic value as the beads are all the same type and the tools have a sophistication that man should not have accomplished at this time. These tools were a “social response to ecological stress.” The eruption made it so that AMH had to band together and trade resources or risk extinction. This solution (social solution) remained a part of human interaction even after AMH escaped extinction and is a critical part of today’s horticulture society.

Another aide to the development of society was the usage of ritual: a rule-governed pattern of formalized, attention-demanding behavior. The main usage of ritual in mammals is to confront tense or awkward situations in a way that releases tension. It draws attention away from threatening cues and defensive responses and so creates conditions for extended social interaction. Ritual behavior is also the basis of many other social and cognitive skills and so no matter how few rituals were observed, the fact that they happened at all served as a keystone to the development of social bonds.

Origins of Modern Cognition

Archaeologists have suggested that modern cognition is based on the use of symbols to organize behavior. Put another way, symbols help us organize our society by having a set standard (think of the alphabet). The symbols have purely arbitrary value decided by the culture that uses them. The reason we are able to use these symbols as social cues is because of the increase in working memory during this period. We gained the ability to hold goal-relevant information while completing other tasks. This increased memory combined with the development of symbols, humans began to master the concept of shared intentionality, which is just a fancy way of saying we can understand what another person is doing or thinking and so we can create shared meanings and communicate.

This working memory was also extremely important in the establishment of more complex rituals as these rituals needed increasing levels of self-restraint. The ability to ignore an intuitive response to complete a ritual takes a level of mental fortitude that AMH developed.  Evidence shows that rituals in place to develop group trust and solidarity are the most demanding of self-control and focus. Three main types of social rituals were key in building group alliances and trust: trust building and reconciliation, initiation, and shamanistic.

trust fall
an example of a ritual that we use today where we have to hold back our inhibitions

Rituals of Trust-Building and Reconciliation: These types of rituals likely saw a rise in polarity as AMH started grouping up more and more. Individuals had to show that they could restrain their instinct when it came to interactions with the group to show that they were indeed members who embodied the group’s best interests. The individuals who could not inhibit these instincts were probably left to survive alone as outcasts.

Rituals of Initiation: Even today, over 70% of traditional societies have rites of passage from adolescence to adulthood. As society during this period become more and more complex, the initiation practices became more intense. The ability to have self-control during these rites is a hallmark of the increased working memory needed for symbolic thought.

Shamanistic Healing Rituals: Shamanism combined supernatural authority to social norm which led to increased within group cohesion. Groups that were bonded by these emotionally taxing rituals would more likely exhibit altruism during times of scarcity and this gave the group a fitness advantage over other hominids. These shamanistic rituals were also heavy on their usage of mind altering drugs ad most of the practices during the rituals served the gual of achieving an altered state of consciousness. This process of ritual healing shows evidence of being viable at the time for increasing survival rate and the rituals might have even played a roll in increasing working memory necessary for modern cognition with the mind altering drugs.

The Fortuitous Mutation

Stanford archaeologist Richard Klein’s theory on human development is that the difference between AMH  and other hominins was genetic mutations that restructured AMH’s brains in a way to conduce social interaction resulting in a cognitive advantage. In 1896, three researchers studied the process known as the Baldwin effect which provided a mechanism for allowing environmental phylogenic traits to become genetically expressed through processes of natural selection. Acquired traits do not necessarily affect the genes, but they might create an advantage in these individuals that could contribute to this gene becoming expressed in future generations. Complex cognitive skills could have emerged as a necessity of the environment and as that necessity persisted, the traits required for cognitive abilities were genetically expressed and become stabilized in the gene pool.

Baby Rituals

When we observe rituals in mammals, we can see all of the elements associated (attention-demanding, formalized, rule governed) in interactions between infants and adults. Within an hour of birth, human babies start imitating facial expressions indicating these reactions are more than just reflexes, they are genetically coded and expressed. Even in later infancy, we notice a pattern in mother-child interactions:

  1. Initiation- engage attention
  2. Mutual orientation- excitement calms and voices soothing
  3. Greeting- infant moves limbs, mother more animated
  4. Play Dialogue- take turns making sounds (protoconversation)
We see that this baby has learned the action, so why does she laugh every time we play peek-a-boo?

These elements show that there is a specific order followed, and even if this ritual is not used to confront an awkward situation, it teaches the baby the process of ritual behavior. Why does a baby laugh every single time you play peek-a-boo? It’s not like it has not leaned what is going on, it is part of the ritual of the game (you would be hard pressed to find a baby that doesn’t laugh at peek-a-boo).  These interactions with adults and especially mothers teach infants the critical skills of how to regulate emotions based on interactions, how to use social partners as cues for emotion and as a source of information, and how to use the ritual context to interpret a situation and the emotions attached to it.

The parents of AMH 70,000 years ago did not share this level of intricacy in parent-infant interactions, but ones that showed increased  levels of it were more likely to reproduce and this possibly became a part of genetic code through the Baldwinian process.

Unique Culture Produces Unique Cognition

After all of this, we only have one question: why us? There were other hominids like the Neanderthals that shared many features with us, but did not show this level of cognition. The only differences were the wide ranged trading patterns of AMH and supernatural beliefs associated with shamanistic rituals. Basically, increased social rituals were the only differences that allowed humans to develop cognition and developed highly complex social rituals because of this. The reason humans are so unique, no matter how corny it sounds, is because we worked in groups as a species due to survival needs.



In his essay, "Shamanism as Neurotheology and Evolutionary Psychology," author Michael Winkelman looks at various instances of shamanism across cultures to find similarities that reveal "universals" about the practice.

Dr. Michael Winkelman Associate Professor Arizona State University
Dr. Michael Winkelman
Associate Professor Arizona State University

Winkelman recently retired from his post as an associate professor in the School of Human Evolution and Social Change at Arizona State University to begin studies in Brazil. Winkelman focuses his research on shamanism as medicine, applied medical anthropology, and cross-cultural relations. His knowledge of cross-cultural relations allow him to find these shamanistic "universals" that he argues are the basis of the practice's modern resurgence. After receiving his Bachelors degree from Rice University, Ph.D from the University of California at Irvine, and Masters Degree from the University of Arizona, Winkelman made strides in researching shamanism's ability to heal substance abuse issues as well.

To preface his research, Winkelman starts by noting that shamanism is "humanity's most ancient spiritual, religious, and healing practice" and is currently having a resurgence because it is rooted in the basic functions of the "brain, mind, and consciousness." In the past, this rooting provided shamanism with a functional role in survival and cultural evolution in hunter-gatherer societies. Since shamanistic rituals date back to human prehistory, they produced what Winkelman characterizes as an "evolved psychology" that gives shamanism relevance in a modern society.

In order to have a resurgence however, there must have been a decline somewhere along the line. Confusion about the true nature of shamanism created skepticism because of the variety of shamanistic rituals that span contrasting countries and cultures. Winkelman also adds that the practice's origin outside of the western world and association with altered states of consciousness helped to create a stigma. However, treatments for "spiritual emergencies" and substance addictions have helped prove the worth of shamanistic ritual in modern society.

Modern research, like that done by Winkelman, has helped to empirically prove an association between shamanistic practices and opioid releases in the brain that "enhance serotogenic function." In order to do this, practitioners use a plethora of shamanistic activities and symbols designed to elicit "physiological, psychological, and emotional" responses. When these responses are quantified they form the biological bases of the shamanic "universals." These include shamanistic healers, altered states of consciousness, analogical thought, and community rituals.

Winkelman found in his cross-cultural study that Shamanistic healers are a "universal" in shamanistic  cultures and that they even share many similar characteristics across cultures. The healers share a common background in alternated states of consciousness, which forms the basis for their "universal institutionalization of mechanisms for altering consciousness and healing through integrative brain functioning." Shamans also share many other characteristics such as interpreting illnesses as being caused by spirits, symbolic manipulations for healing, and attributing illnesses to the work of other shamans. Their work focuses on achieving a state of "religious ecstasy" that is a form of altered consciousness. This state causes a natural nervous system reaction that triggers a sense of relaxation and brain synchronization. Lower brain structures are stimulated to create a "synthesis of behavior, emotion, and thought"

Another "universal" in shamanistic healing that has already been mentioned is altered states of consciousness. Rhythmic activities employing music, dance, and mimetic control are frequently used to achieve altered states through theta and alpha wave brain patterns. Rhythmic activities are also beneficial when trying to promote group cohesion. Large groups are able to connect easily through music because it promotes "synchrony, coordination, and cooperation among group members." (Hint: get ready for tomorrow) Visionary experiences are also important in shamanistic healing as the symbolic method as opposed to activity method employed by the rhythmic activities. Winkelman's research finds that these visionary experiences are "a natural brain phenomenon" that occurs when the brain "releases the normal suppression of the visual cortex."

Combining ritual songs and dance is one of the most common ways to achieve an altered state of consciousness
Combining ritual songs and dance is one of the most common ways to achieve an altered state of consciousness


Analogical thought is also often present in shamanism as Winkelman finds that innate processing modules for natural history of intelligence nand mental attributions regarding "others" manifest themselves in shamanism through analogs. Animism, animal allies, and examples of self-representational death and rebirth all reflect preverbal brain structures dating back thousands of years. Animism involves the attribution of of human mental and social capabilities to animals, nature, and the unknown. According to Winkelman's research, organisms model their own mental states to other organisms mind and behavior. Animal allies also employ the natural history model that animism employs, but involve representations of "sacred others" and attribute more specific brain capacities to specific animals. Soul Flight as well as death and rebirth experiences are also universally manifested in shamanism. A common example of this is a near death experience where the soul goes on a momentary "journey."

Community rituals are also highly important to shamanism as attachment and affectional bonds are also helpful in releasing the natural brain opiates necessary for healing. These opioids are known for stimulating the immune system, providing senses of euphoria, certainty, and belongingness, enhancing coping skills, maintaining homeostasis, reducing pain, decreasing stress levels, and allowing for greater environmental adaptation. Community rituals are important in treating "soul loss" which is one of the main shamanic illnesses. Shamans also use cultural symbols that the community helps to reinforce in order to manipulate physiological responses. Symbols can manifest themselves unconsciously, allowing shamans to heal through advanced methods of engagement with "neurocognitive structures to produce therapeutic changes."

Can anyone guess what some of these pre-verbal shamanistic symbols are?
Can anyone guess what some of these pre-verbal shamanistic symbols are?

Through these "universal" processes, shamanistic healing allows for the restructuring of ego and identity in the person. The "universals" that Winkelman found in his research also help to create a special mode of consciousness that creates synchronized brain wave discharge patterns. These patterns help to coordinate the hierachical functions of the brain in a more positive manner. Through better coordination of the functional levels of the brain in this state of consciousness, the self is better able to induce personal, cognitive, and social integration as a means of healing.

Overall, the main points to take away from Winkelman's research are...

  • Shamanism has experienced a resurgence in modern society as it reflects basic concepts of human nature
  • Shamanism's healing powers come from creating an altered state of consciousness that release natural opiates stimulating serotonin flow.
  • Shamanistic healing rituals alter physiological, psychological, and emotional responses by using activity (dancing, music) and cultural symbols.



Mark Schaller is a psychological scientist and Professor of Psychology at the University of British Columbia.  He graduated from the University of North Carolina in 1984 and obtained a PhD in Psychology at Arizona State University in 1989. He's been at his current position at the University of British Columbia since 1996. Schaller's research looks into the cognitive processes that contribute to stereotypes and prejudices, as well as the implications of evolutionary fundamental human motives on social behavior, the psychology of kin recognition, and the psychological consequences of fame. The reason that he's important for our class at this very moment has to do with his research into and coining of the term "behavioral immune system."

Mark Schaller Department of Psychology  University of British Columbia
Mark Schaller
Department of Psychology
University of British Columbia

So, to talk about the Behavioral Immune System, first we have to talk about the immune system. You know, that pesky little piece of your body that throws out fevers, sweating, swelling, et al. to deal with the stress you put your body through? Well, this system is actually very metabolically costly in its attempts to keep the body healthy. To mitigate the risk of these costs ever being incurred in the first place, human immune systems have also developed behavioral mechanisms that can prevent contact with foreign and harmful pathogens. We call this system of preventative behaviors the Behavioral immune system. Any time that you feel the need to stay away from people with known illness, you're experiencing the most obvious results of this system.

Other examples of this kind of proactive avoidant behavior can be seen in nature: Schaller lists tadpoles, mice, and chimpanzees as animals that are known to actively avoid other members of their species that are noticeably ill. The primary emotion that is associated with studies of this system is disgust, and Schaller seeks to examine how these feelings can effect social cognition and interaction within a given social ecology.

So, the Behavioral Immune system can be subdivided into two sorts of behaviors- detection and response. Detection primarily depends on smell and sight to find possible risks of infection around you. This includes both objects and behaviors of those around you who may be a vector of disease. The objects that subjects experience revulsion towards seem obvious-- fecal matter, vomit, etc. When it comes to how you react to those around you, however, that's where the research gets interesting. Test groups not only responded with avoidant behavior to those who were obviously sick or clearly unhygienic, but also to those who seemed visibly different from the cultural norm. The reasoning seems to be that those who are from outside of the local culture pose a threat not only because they may carry unusual pathogens, but also because they haven't been taught the local methods of hygiene. The findings don't stop there, however; there is also revulsion associated with those who are a part of the culture but differ from the "healthy" norm: the obese, the very old, the disabled. This can all be explained by the vast array of symptoms that may be signs of disease; the system over regulates because a false positive is less likely to cause harm than a false negative assumption of disease.

This guy's probably CRAWLING with unnatural diseases
This guy's probably CRAWLING with unnatural diseases

Interestingly enough, test groups didn't always experience these feelings of xenophobia or revulsion. Subjects who were more cognizant of the risks of disease were more likely to want to avoid outsiders and less likely to even be friendly within their own social groups. In one experiment, groups who were exposed to a video warning about the dangers of disease and foreign pathogens were much less likely to want to recruit workers from less well known or "unsafe" countries than those who watched a video about workplace accidents. In the real world, this translates into stronger feelings of xenophobia and fewer allowances for those who are "free thinkers" or otherwise non-normative in cultures which have historically higher rates of pathogen activity and greater diversity of pathogens, such as in equatorial regions.

So, funnily enough, the guy with the butt tattoo is statistically more likely to revolted by this meeting. To be fair, they ARE British.
So, funnily enough, the guy with the butt tattoo is statistically more likely to revolted by this meeting. To be fair, they ARE British.

This sort of predisposal towards those that the behavoiral system interprets as safe can also be seen in mate selection. Part of Schaller's findings showed predispositions towards less sexually promiscuous and more attractive partners that followed the same sort of increase in areas where pathogenic activity is high. This stems both from the increase in possible vectors of infection when partners are sexually active with multiple persons as well as the perceived genetic purity of those with symmetric faces. 

Schaller concludes the article with a look into the portions of the system that are as yet not well understood. The Behavioral immune system does not exist in a vacuum, and many of the systems and behavioral cues that the system encourages also serve to help other, older systems. An easy target is the fact that the eyes and olfactory system obviously didn't evolve purely to spot pathogens. However, even disgust and revulsion, the primary forces of the system, were most likely coopted from the need to vomit and expel harmful substances once ingested. Additionally, though xenophobia, regulatory behavior within a social circle, and distrust of non-normative behavior are all tools of the system, there are other behaviors thought to play a role. People like doctors, soldiers, and youth and aged caretakers are all constantly participating in behaviors that increase the risk of pathogen infection, yet they enjoy positions of respect in most cultures. The sorts of assumptions of personal risk in exchange for lowered risk for the larger culture are still not very well explained by the Behavioral Immune System model.


Rebecca Seligman is a medical and psychological anthropologist at Northwestern University. Seligman received her PhD from Emory in 2004. Her current research looks into both the mental and physical health of Mexican Americans, specifically between diabetes and depression.  Her work on dissociative experience and cultural neuroscience, with Laurence Kirmayer, was published in 2008. Kirmayer is a MD of transcultural psychiatrist and currently a professor of psychiatry at McGill University.

All dissociation falls into one of three classifications: a neurological reaction brought on by stress or trauma; social performance or ritual; and fluctuations in everyday consciousness, which generally go unnoticed.  It is often thought that even though these three forms of dissociation are caused by three different things, the psychophysiological mechanisms that induce these altered states are the same. Unfortunately, we don't know enough about the underlying functions of dissociation to draw any conclusions. Through our desire to learn more about dissociation, two different approaches or paradigms have been developed.

The first is a psychiatric paradigm which is derived from clinical research on stress and trauma induced dissociation. Psychiatric dissociation is referred to as "adaptive" and it postulates that dissociation is a biological function and a natural mechanism of our subconscious triggered by emotional feedback. Fugue states, amnesia and identity disturbances are examples of neurological issues psychologists focus on when referring to dissociation. Many researchers in the psychiatric paradigm believe stress and trauma reactions were evolutionary precursors to dissociation. Dissociation allowed our early ancestors to enter a trance state to reduce anxiety and stress during traumatic events, similar to trance states experienced by many animals before death. The trauma survivors go into what's referred to as "dissociatiave coping" which minimizes or even eliminates memories of traumatic experiences that could be triggered by almost anything and cause extreme emotional reactions. When we don’t completely dissociate post-traumatic stress disorder can frequently develop.

 The second discipline is the anthropological paradigm which was built on research of social dissociation which is generally confined to religious and spiritual practices or healing ceremonies.  This social idea is known as "discursive" (as opposed to this blog which some might call "distyping"). From the anthropological aspect discursive dissociation is a social behavior that requires people to become immersed in cultural practices designed to distance them from preconceived thoughts and notions.  Social dissociation cultures frequently use spirit possession as a way to show status or power, and advance socially. Standards, customs, and rituals vary so drastically from culture to culture that few anthropologists attempt to define dissociation as a whole, but rather attempt to understand it within the constraints of a specific cultural group.

The two paradigms seem to share few similarities on the surface, which has created what Seligman and Kirmayer refer to as a "false dichotomy". The problem with this is that many people feel compelled to side with one of the two disciplines. Due to this many people either feel dissociation is adaptive and all dissociative symptoms are due to neurological mechanisms responding to emotional stimuli, OR dissociation is purely a social byproduct and it allows people to communicate feelings, establish communal hierarchy and follow cultural expectations. But like most things in the world, the process of dissociation is not black and white. Seligman and Kirmayer suggest that significant progress in each respective fields could be achieved if the two sides worked together. Many aspects of both the psychiatric and anthropological definitions are not mutually exclusive, in fact Seligman and Kirmayer say we need an integrative view of dissociation if we want to fully understand the meaning and mechanics.

The psychiatric-adaptive discipline is the most widely held view point and is considered the dominant paradigm, encompassing all stress and trauma related dissociation. Most of this dissociation is normal and we’ve probably all experienced it, maybe without even realizing it. But a small amount of this is considered pathological dissociation which covers fugue states and amnesia like mentioned before, but also includes PTSD and many other stress and trauma related disorders. These can affect everyday perception, cognition and attention, as well as disorganize and compartmentalize memories. Depersonalization and derealization are also serious problems of dissociative coping. The prior causes you to feel like you’re only watching your life but someone else is controling it (which sounds absolutely horrifying), and the latter makes you question if you, your friends, the world and everything else around you even exists.  These ailments are predominant in Euro-American countries where trance states and social dissociation are rare, yet people are always told to “talk about your feelings”.  In the Eastern world (and many still developing areas across the globe) dissociation, meditation, and social performances are common. In these areas stress and trauma related disorders are rarely reported or observed dissociative researchers. A great example of this was a study done by Wikan in 1990. The Balinese have been taught to avoid extreme emotion, and use dissociation as a coping method for stress almost daily. They maintain a smooth demeanor and show little emotion to not disturb spirits and upset the Gods. The Balinese believe that if emotion is displayed at the death of a loved one the spirit will be harmed in passing and may never find its final resting place.  During these times they partake in religious and performance dissociation practices, and have been recorded with lower levels of stress during this time as well.

According to Seligman borrowing ideas and knowledge from the opposite paradigm could have significant benefits, and should always be looked into. Take the Balinese in the story above for example; a social dissociative culture that developed stress reducing methods has had many psychiatric practitioners observe and research their culture and habits in the same fashion an anthropologist normally would. Similarly, many anthropologists could benefit from psychiatric work when modeling based on hypnosis to compare to the cognitive functioning of a research group. Developing future understandings of cognitive mechanisms and evolutional background will create an atmosphere in which social and psychological ideas will be more interchangeable, but the two paradigms working together may be the only way that happens and we truly understand dissociation.