Ground Zero: Dehumanization

Photo by Gerd Altmann

Welcome to the Jungle!

It is impossible to find a reliable source of accurate information in the information jungle. The number of sources grows exponentially. Their reliability decreases at approximately the same speed. The only solution remains to independently verify the accuracy of all information received from any source irrespectively of how reliable that source was in the past.

Chapter One. The Miracle

In this chapter, we will learn that the brains of our ancestors were growing very rapidly for three million years, most probably for the reason that expansion of the surface area of the cerebral cortex locked into a positive feedback loop with the cultural evolution of the human species.

About three million years ago the brains of some hominid species began to gain volume much faster than the brains of all mammals including other primates. Since then those hominids had become human species and had tripled the size of their brains that became over six times larger than the brains of any other mammals of similar body size.

Summary

The brains of our ancestors began to rapidly increase about three million years ago. Since then and until about ten thousand years ago the unprecedented growth continued. Humans needed wider contacts with stranger clans to gain access to information they didn’t know. The brain capacity to carry wide cognitive maps was required to be in accord with strangers and to understand dissenting knowledge that strangers possess. In the face of frequent and severe environmental fluctuations, cumulative cultural evolution became the crucial condition for the survival of the human species and stimulated individual brains to grow.

References:

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  4. Alexander S. Balankin, Didier Samayoa Ochoa, Israel Andrés Miguel, Julián Patiño Ortiz, and Miguel Ángel Martínez Cruz, Fractal topology of hand-crumpled paper, Phys. Rev. E 81, 061126 — Published 17 June 2010, https://doi.org/10.1103/PhysRevE.81.061126
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  10. Claude Lévi-Strauss (1985). The View from Afar, Chapter 1, Race and Culture, page 24

Chapter Two. The Grand Reversal

In this chapter, we will discover that an abrupt reversal in the direction of the change in the human brain’s volume took place about ten thousand years ago and will search for its cause.

After three million years of growth, the miracle vanished in the blink of an evolutionary eye. Measurements of fossil skulls from all inhabited continents clearly show that our brains have become about 10% smaller in the past 10,000 years.

Summary

The rapid shrinking of human brains began about ten thousand years ago. Although there’s no decisively plausible explanation of the process, the growth of the population density beyond a particular threshold linked to the switch from the hunter-gatherer style of life to the one of an agricultural settler coincided with the u-turn of brain volume dynamics. Rendering of the rapidly changing objective reality is the most computationally intensive function of our brains. The brain of an average person was less in use once the reality became settled with recurring predictable changes.

References:

  1. Bridget Alex, The Human Brain Has been Getting Smaller Since the Stone Age, Discover Magazine, April 9, 2019
  2. John Hawks (2011) Selection for smaller brains in Holocene human evolution
  3. Mummert, Amanda & Esche, Emily & Robinson, Joshua & Armelagos, George J., 2011. “Stature and robusticity during the agricultural transition: Evidence from the bioarchaeological record,” Economics & Human Biology, Elsevier, vol. 9(3), pages 284–301, July.
  4. Henneberg, M. (1988). Decrease of Human Skull Size in the Holocene. Human Biology, 60(3), 395–405. http://www.jstor.org/stable/41464021
  5. Kathleen McAuliffe, If Modern Humans Are So Smart, Why Are Our Brains Shrinking?, Discover Magazine, January 20, 2011
  6. Charles Q. Choi, Humans Still Evolving as Our Brains Shrink, Live Science, November 13, 2009
  7. Jonathon Keats, Has social living shrunk our brains? NewScientist 14 May 2014
  8. A film by Mike Judge, Idiocracy (2006)
  9. Gerald R. Crabtree, Our fragile intellect. Part II, Trends in Genetics, November 13, 2012, DOI: https://doi.org/10.1016/j.tig.2012.10.003
  10. Gerald R. Crabtree, Rethinking our intellectual origins: response to Kalinka et al., Trends in Genetics, February 18, 2013, DOI:https://doi.org/10.1016/j.tig.2013.01.013
  11. Fu, W., O’Connor, T. D., Jun, G., Kang, H. M., Abecasis, G., Leal, S. M., Gabriel, S., Rieder, M. J., Altshuler, D., Shendure, J., Nickerson, D. A., Bamshad, M. J., NHLBI Exome Sequencing Project, & Akey, J. M. (2013). Analysis of 6,515 exomes reveals the recent origin of most human protein-coding variants. Nature, 493(7431), 216–220. https://doi.org/10.1038/nature11690
  12. Tia Ghose (November 12, 2012) Are Humans Becoming Less Intelligent?
  13. Jaleal S. Sanjak, Julia Sidorenko, Matthew R. Robinson, Kevin R. Thornton, Peter M. Visscher, Contemporary directional and stabilizing selection Proceedings of the National Academy of Sciences Jan 2018, 115 (1) 151–156; https://doi.org/10.1073/pnas.1707227114
  14. Chao Liu et al. (28 January 2014) Increasing breadth of the frontal lobe but decreasing height of the human brain between two Chinese samples from a Neolithic site and from living humans https://doi.org/10.1002/ajpa.22476
  15. Claude Levi-Strauss (1962) The Savage Mind
  16. In Russian. А. Н Колмогоров. Автоматы и жизнь, Математика — наука и профессия. (Библиотечка “Квант”, вып. 64.) М. — Наука, 1988, с. 43–62.

Chapter Three. Dead Reckoning

In this chapter, we will find out how the huge improvement in the efficiency of human performance has been achieved at the expense of the reduction of the raw human brainpower.

There are no such directional instructions as ‘turn left’ or ‘turn right’ in several languages of Australian aborigines, the language of Maya in America, and some rural languages in Asia. Those languages use an absolute rather than relational reference frame, as linguists name it. Left and right are relational to the orientation and position of a person using them as a reference. West and east remain the same irrespectively of the person’s orientation. Therefore the former frame of reference is named relational or egocentric while the latter is absolute or allocentric.

Summary

We structure the environment around us from the first day of our existence. The objective reality as we perceive it in our consciousness is itself a product of that structuring. Humans achieve the best result with the lowest energy cost by following already existing patterns. Structuring the environment or navigating it anew consumes much more energy and is way less efficient than the utilization of an already existing structure. However, such a huge efficiency improvement comes at a cost: our brain shrinks and we become less smart.

References:

  1. Toni Gomila, Verbal Minds: Language and the Architecture of Cognition, Elsevier, 2012, https://doi.org/10.1016/C2010-0-67019-2
  2. Asifa Majid, Melissa Bowerman, Sotaro Kita, Daniel B.M. Haun, and Stephen C. Levinson (2004) Can language restructure cognition? The case for space, Trends in Cognitive Sciences. 8 (3): 108–114. doi:10.1016/j.tics.2004.01.003
  3. Penelope Brown (2012) Time and Space in Tzeltal: Is the Future Uphill? Frontiers in Psychology. doi: 10.3389/fpsyg.2012.00212
  4. Ramesh C. Mishra, Sunita Singh, Pierre R. Dasen (2009) Geocentric Dead Reckoning in Sanskrit- and Hindi-Medium School Children, First Published August 17, 2009, https://doi.org/10.1177/1354067X09343330
  5. Lorelei R. Howard, Amir Homayoun Javadi, Yichao Yu, Michelle M. Loftus, Laura Staskute, Hugo J. Spiers. The Hippocampus and Entorhinal Cortex Encode the Path and Euclidean Distances to Goals during Navigation. Open Access Published: June 05, 2014, DOI: https://doi.org/10.1016/j.cub.2014.05.001
  6. New research explains how we use the GPS inside our brain to navigate, 9 June 2014, UCL News
  7. Eleanor A Maguire, Katherine Woollett, Hugo J Spiers. London taxi drivers and bus drivers: a structural MRI and neuropsychological analysis. Hippocampus 2006;16(12):1091–101. DOI: 10.1002/hipo.20233
  8. Poulter, S., Lee, S.A., Dachtler, J. et al. Vector trace cells in the subiculum of the hippocampal formation. Nature Neuroscience (2020). https://doi.org/10.1038/s41593-020-00761-w

Chapter Four: The Blessing and the Curse of Artificial Environment

In this chapter, we review the paradox of human adaptation to the artificial environment that, on the one hand, makes us more fit as a species and, on the other hand, reduces demand for our individual natural intelligence.

“The world we live in today is much more a man-made, or artificial, world than it is a natural world. Almost every element in our environment shows evidence of human artifice,” Herbert Simon, the American scientist who was awarded both the Nobel Prize in Economics and The Turing Prize in Artificial Intelligence wrote in his seminal book The Sciences of the Artificial. He believed that the human mind and brain belong to the family of symbol systems, which “are almost the quintessential artifacts, for adaptivity to an environment is their whole raison d’être. They are goal-seeking, information-processing systems, usually enlisted in the service of the larger systems in which they are incorporated.”

Summary

Human brains are shrinking because of their evolutionary advantageous ability to adapt to the environment better than the brains of other animals. Humankind has created for itself an artificial ecological niche that, on one hand, is enhancing our chances for survival and successful reproduction but, on the other hand, is leading to the decrease of our intellectual abilities. Brain shrinking happens because our brains are adapting to the well structured artificial niche without the need to structure the raw signal from the natural environment.

References:

  1. Herbert Simon (1969) The Sciences of the Artificial
  2. Aida Gómez-Robles, William D. Hopkins, Steven J. Schapiro, and Chet C. Sherwood, Relaxed genetic control of cortical organization in human brains compared with chimpanzees, PNAS December 1, 2015, 112 (48) 14799–14804; first published November 16, 2015; https://doi.org/10.1073/pnas.1512646112
  3. George Washington University, Nature and nurture: Human brains evolved to be more responsive to environmental influences, Phys.org, November 16, 2015

Chapter Five. The Hippocampus Is Shrinking in Our Brains Right Now

In this chapter, we find out how switching to narrow cognitive maps in navigation through the well structured and labeled artificial environment leads to the decrease of use of the hippocampus, the brain area responsible for rendering and support of broad cognitive maps.

In the very depths of the temporal lobes of the brain, a pair of seahorses is lurking — the left one and the right. The sixteenth-century Venetian anatomist Julius Caesar Aranzi was highly imaginative. It was with his light hand that seahorses settled in the brain. It’s good that not silkworms. At first, Aranzi thought that the hippocampus extracted from the brain looked more like them.

Summary

The hippocampus and cortical areas anatomically connected to it create, render, update, and objective reality and other wide cognitive maps in our brains. The hippocampus is shrinking in the brains of modern humans because the need for wide cognitive maps in day to day life of modern humans is diminishing.

References:

  1. Anand, K. S., & Dhikav, V. (2012). Hippocampus in health and disease: An overview. Annals of Indian Academy of Neurology, 15(4), 239–246. https://doi.org/10.4103/0972-2327.104323
  2. Salpekar J. A. (2019). Reality Is in the Posterior Hippocampus: Who Knew?. Epilepsy currents, 19(5), 305–306. https://doi.org/10.1177/1535759719868459
  3. Howard Eichenbaum. The role of the hippocampus in navigation is memory. Journal of Neurophysiology, Vol. 117, №407, APR 2017, https://doi.org/10.1152/jn.00005.2017
  4. Lisa Nobis et al. Hippocampal volume across age: Nomograms derived from over 19,700 people in UK Biobank. NeuroImage: Clinical, Volume 23, 2019, 101904, https://doi.org/10.1016/j.nicl.2019.101904
  5. John O’Keefe and Lynn Nadel (1978) The Hippocampus as a Cognitive Map
  6. Veronique D. Bohbot et al. Virtual navigation strategies from childhood to senescence: evidence for changes across the lifespan, Frontiers in. Aging Neuroscience, 15 November 2012, https://doi.org/10.3389/fnagi.2012.00028
  7. Chet C. Sherwood et al. Aging of the cerebral cortex differs between humans and chimpanzees, PNAS August 9, 2011, 108 (32) 13029–13034; first published July 25, 2011; https://doi.org/10.1073/pnas.1016709108

Chapter Six. Reduction of the Hippocampus Shrinks Objective Reality and Damages Health

You will learn more about the major cognitive functions of the hippocampus in Section Four of this book.

In brief, the hippocampus, densely interconnected with the cortex and other major parts of the brain, supports the flexible use of information in all possible contexts. Damage to the hippocampus can produce inflexible and maladaptive behavior in such diverse areas as memory, navigation, exploration, imagination, creativity, decision-making, character judgments, establishing and maintaining social bonds, empathy, social discourse, and language use.

Summary

As you can see now, the hippocampus is a very sensitive and very dynamic area of the brain. The comfortable and highly efficient artificial environment is our major competitive advantage in the adaptation to the natural environment given to us in an unstructured and unpredictable form of natural (not artificially structured) sensations. That artificial environment protects us from structural (unexpected) uncertainty that has shaped our brain and hippocampus. Structuring of the objective reality keeps our brain and hippocampus in particular in good shape because they were designed for that purpose.

References:

  1. Rachael D. Rubin et al. The role of the hippocampus in flexible cognition and social behavior. Frontiers in Human Neuroscience, Published online 2014 Sep 30. doi: 10.3389/fnhum.2014.00742
  2. Aaron Barriga (Feb 21, 2019) What Alzheimer’s Has to Say about Your Eyesight
  3. Russell W. Chan et al. Low-frequency hippocampal–cortical activity drives brain-wide resting-state functional MRI connectivity. PNAS August 15, 2017, 114 (33) E6972-E6981; first published July 31, 2017; https://doi.org/10.1073/pnas.1703309114
  4. Guo-Ping Peng et al. Correlation of Hippocampal Volume and Cognitive Performances in Patients with Either Mild Cognitive Impairment or Alzheimer’s disease. CNS Neuroscience & Therapeutics 21 (2015) 15–22
  5. Melanie Ring et al. Structural learning difficulties implicate altered hippocampal functioning in adults with autism spectrum disorder. Journal of Abnormal Psychology, 126(6), 793–804. https://doi.org/10.1037/abn0000277
  6. B Cao et al., Hippocampal subfield volumes in mood disorders. Molecular Psychiatry 22, 1352–1358 (2017). https://doi.org/10.1038/mp.2016.262
  7. Nils Opel et al. Hippocampal Atrophy in Major Depression: a Function of Childhood Maltreatment Rather than Diagnosis? Neuropsychopharmacology. 2014 Nov; 39(12): 2723–273. doi: 10.1038/npp.2014.145
  8. Katherine L.Narr et al. A Twin Study of Genetic Contributions to Hippocampal Morphology in Schizophrenia. Neurobiology of Disease, Volume 11, Issue 1, October 2002, Pages 83–95. https://doi.org/10.1006/nbdi.2002.0548

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