Neuroanthropology: Brain Enculturing

Neuroanthropology: Brain Enculturing
 Through the lens of the Capoeira Angola  

Neurobiologists have long endeavored to discover whether or not culture has a physical implication (causes reconstruction) of the brain.  Through the use of the concept of embodied cognition, whereas brain activities such as motor skills, perception, and above all, equilibrium, are stressed, a new observation can be made providing support for the concept that the brain can, indeed, be restructured due to cultural implications.  This observation is made through the careful analysis of a specific group of Brazilian martial artists, called capoeiristas, who undermine the concept of a set form of equilibrium: their techniques and assaults are often completed from an inverted headstand or handstand.  Recent studies have shown that, over long periods of time and practice of a certain skill, the equilibrium of an individual and the adaptation of motor skills can be changed.  This change seems to result in a reconstruction at the neuronal level in the nodular equilibrium system and, perhaps, the motor cortex.  Let us delve into the concept of brain plasticity and culture’s specific implication.

Some aspects of human culture, such as art and verbal communication, are shared by all cultures. Other aspects are specific to particular cultures, each of which has its own customs and ritualistic behaviors.  For this paper’s analysis, it is necessary to call upon the specific cultural implication of the Capoeira Angola, the traditional style of the Afro-Brazilian martial arts practiced solely in parts of Brazil.  This form of martial arts, which can be resolved to be an important form of culture in Brazil, involves fighting techniques in an inverted posture of headstand and handstand (2).  These practitioners of Capoeira, called capoeiristas, move skillfully about in this inverted position, engaging in seemingly-impossible martial arts assaults.  If the Capoeira does produce reconstruction of the brain, a connection between cultural association and brain structure becomes increasingly plausible.

In recent years, neurobiologists have concentrated on a new wave of brain science, called embodied cognition.  This term highlights other brain activities, such as motor, perceptual and regulatory functions, and the influence of embodiment on thought itself (2).  Capoeiristas claim that their arduous training regimens produce perceptual, psychological and physiological transformations of their brain (2).  If this thought has neuronal backing—that is, if the brain’s plasticity does indeed allow restructuring to incorporate embodied cognition changes such as the ones capoeiristas insinuate—observations can be made regarding the differing structure of brains with emphasis on culture. 

In the past, brain theorists have argued that equilibrium, specifically, is a pre-programmed part of the brain (2).  However, we see that in the art form that the capoeiristas practice, the concept of equilibrium is drastically changed: the participants often engage in martial arts while balancing upon their head.  The ethnological miscellany of equilibrium training, and the plasticity of a certain ‘nodular’ system, undermines the argument that a pre-programmed equilibrium module is unaffected by outside information, such as training (2).  This demonstrates, instead, that even this basic and largely unconscious neural function can be encultured (2).

Let us examine the neurology of plasticity with regard to equilibrium and this nodular system.  Although psychologists typically say that the organ of balance is the vestibular system (located in the inner ear), equilibrium can also be regarded as a sensory system (2). In daily activities, people maintain their upright posture by using a number of senses and largely unconscious postural adjustment strategies (2).  For example, the upright posture is maintained by sensations from the vestibular system, the semicircular canals in the inner ear and the otoliths; but also by proprioceptive receptors (2).  These receptors in our muscles tell the brain the position of joints, the amount of tension and pressure present, et cetera (5). Using this information, our brain works out the positioning of our joints and limbs, and understands how they relate to each other (4). 

In other words, the ‘sense’ of balance is actually a amalgamation of diverse inputs and often-unconscious patterns of compensatory behavior (2).  This theory of equilibrium can be simplified such a concept: confronted with challenges that vary according to situation, the equilibrium system must ‘re-weight’ the various inputs, sort out disparities between sensory flows, discount or completely disregard misleading proprioceptive, vestibular or visual information (2). 

Let us bring this concept into the Capoeira with emphasis on their headstand, called a bananeira.  Although comparable laboratory data on the bananeira is not available yet, ethnographic observation offered by Greg Downey, scholar of Capoeira, may provide useful observations. Downey conceptualizes that, with the head position fully inverted with emphasis on the fact that vision is essential to tracking an adversary, both vestibular and visual information are severely compromised for balancing purposes (2). The only other candidates to maintain equilibrium in the bananeira are touch, proprioception and righting behaviors.  Downey suspects that capoeiristas maintain inverted balance by relying more heavily on proprioception and sensitivity through the hands, coupled with a very quick, refined learned pattern of hand-stepping reflexes (2).  It is thus plausible that these proprioceptive and sensitive equilibrium states have evolved through long-term training and task re-weighting.

This provides a strong observation that the equilibrium system can be manipulated physically and is not a pre-programmed entity.  Given the evidence of variable  inputs, trainability, cultural variation, and task-specific re-weighting, the equilibrium system looks more ‘nodular’ than ‘modular’; that is, rather than being pre-programmed by evolution, the equilibrium system acts as a malleable network of sensory inputs differently weighted, neural resources that can learn to interpret different information streams and trainable behavioral patterns (2) at the neuronal level.  This nodular modeling of the equilibrium system helps us also to see the many ways that cultural regimes, patterns of experience, explicit coaching, conscious training, and unconscious conditioning might affect the system of an individual according to situation (2).

In order for the brain to be nodular, a restructure at the neuronal level is necessary.  Restructuring can arise in a number of different places in the network.   For example, extensive training might strengthen connections between distinct kinds of visual inputs and the body’s network of perceptual and reflex actions that maintain equilibrium; or the network dedicated to equilibrium could be trained to provide stimulation to the hands, shoulders, arms and other parts of the body necessary to maintain a bananeira, rather than just the legs in typical bipedal posture (2). The enculturation could result in modified weighting by the vestibular nucleus, or it may occur in more immediate peripheral modifications to the nervous system (2).

It is the active interaction that provides physical changes in the structure of the brain (1).  It is only in the last decade or so that we are able to demonstrate that these changes have taken place at the level of neurons (1) by usage of neuroimaging, for example.

To add to these previous observations and subsequently plausible conclusions, one can regard this equilibrium adaptation that capoeiristas master as a form of motor adaptation: that is, with practice, the body learns the concept of a specific task.  This effect of motor adaptation, combined with a study by Li et al., hypothesizes that learning-related improvements in these tasks are possible because of plasticity, not only in the nodular system of balance, but also in the motor cortex (3) at the neuronal level.

Studies in monkeys have shown that, after training on specific tasks, the organization of the motor cortex can alter such that trained limbs acquire a disproportional representation within the cortex (3). Although there may be separate neuronal mechanisms underlying short-term and long-term motor learning (like learning to drive a new car versus the inverted skill of the capoeiristas), the concept of change in the motor cortex sheds new light on implications of culture upon specific parts of the brain (3).

In conclusion, we have adequately provided a consistent and strong observation through the use of capoeiristas to offer evidence that the culture physically affects the neuronal structure of the brain—in other words, that the brain can be ‘encultured’.  The ability of our brains to adapt to circumstances is important not just for acquiring new skills, like martial arts and changed equilibrium, but for recovery from brain injuries such as stroke (which often involves a reorganization of the cortex such that duties originally performed by damaged areas are assumed by healthy tissue). 

In light of the concept of a bi-partite brain, we understand that the storyteller (cognitive conscious) is influenced by the rest of the cognitive unconscious and the cognitive unconscious is influenced by the body and nervous system.  The body is in turn influenced by the outside world, such as culture.  It is therefore plausible that traces of that culture can be found in unique brains.  Specifically referring to the above mentioned observations, these traces of culture can be conceivably evident in the motor cortex and nodular equilibrium system. 

 References 

1.      Ashley, M (2004). Traumatic Brain Injury: Rehabilitative Treatment and Case Management. CRC Press. 

2.      Downey, Greg (2008, November 30). Balance between cultures: equilibrium training. Retrieved May 6, 2009, from Neuroanthropology Web site: http://neuroanthropology.net/2008/11/30/balance-between-cultures-equilibrium-training/ 

3.      Jackson, A & Lemon, R.N., (2001). Motor control: Forcing neurons to change. Science Direct, Current Biology, Retrieved May 4, 2009, from http://download.cell.com/current-biology/pdf/PIIS0960982201004158.pdf?intermediate=true 

4.      Mo, (2006, October 27). Culture on the Brain. Retrieved May 6, 2009, from Neuroanthropology: Neurophilosophy Web site: http://neurophilosophy.wordpress.com/2006/10/07/neuroanthropology-culture-on-the-brain/ 

5.      Pritt, Alan (2006). Proprioreception Exercise. Retrieved May 6, 2009, from Improve Human Intelligence Web site: http://www.improvehumaniq.com/proprioception-exercise.html