VII. Earthomo Sapiens: A Major Evolutionary Transition in Individuality
3. A Complementary Brain and Thought Process
Chai, Lucy, et al. Functional Dynamics of the Language System. Cerebral Cortex. 26/11, 2016. In this section and elsewhere, are entered a growing number of citations about dual, reciprocal brain faculties such as fast and slow (Evans), creativity (Otis, Wolf), autism (Crespi), metastability (Kelso), and more. Here University of Pennsylvania and MIT neuroscientists including Evelina Fedorenko and Danielle Bassett report an iconic instance with regard to the processing of linguistic activities. While a “core” recognition of discrete words occurs in the left hemisphere, the right hemisphere provides the vital “peripheral” mode of content comprehension and meaningful value.
During linguistic processing, a set of brain regions on the lateral surfaces of the left frontal, temporal, and parietal cortices exhibit robust responses. These areas display highly correlated activity while a subject rests or performs a naturalistic language comprehension task, suggesting that they form an integrated functional system. Evidence suggests that this system is spatially and functionally distinct from other systems that support high-level cognition in humans. Yet, how different regions within this system might be recruited dynamically during task performance is not well understood. Here we use network methods, applied to fMRI data collected from 22 human subjects performing a language comprehension task, to reveal the dynamic nature of the language system. We observe the presence of a stable core of brain regions, predominantly located in the left hemisphere, that consistently coactivate with one another. We also observe the presence of a more flexible periphery of brain regions, predominantly located in the right hemisphere, that coactivate with different regions at different times. By highlighting the temporal dimension of language processing, these results suggest a trade-off between a region's specialization and its capacity for flexible network reconfiguration. (Abstract)
Chaiken, Shelly and Yaacov Trope, eds.
Dual-Process Theory in Social Psychology.
New York: Guilford Press,
A large collection which addresses the reciprocal and sequential ways our brains learn, think and respond. Much theoretical writing but throughout these studies of attitudes, perceptions, social cognition and so on, a constant, interactive duality is reported of associative, emotional or rule-based, cognitive modes. As an overall observation, it is indicative of how specific disciplines such as Social Psychology are so isolated that nowhere in the book or index is there any mention of corresponding neural substrates, even though these dual properties align well with the right and left brain hemispheres.
Chiron, C., et al. The Right Brain Hemisphere Is Dominant in Human Infants. Brain. 120/1057, 1997. The right hemisphere traits of visuospatial and emotional abilities develop earlier for purposes of individual and species survival. A child’s left brain begins its growth spurt at about two years of age.
Christman, Stephen, et al. Individual Differences in Risk Perception versus Risk Taking. Brain and Cognition. 63/1, 2007. Right brain hemisphere processes are more sensitive and averse to risk than the left side. Women are thus more likely to avoid perilous situations than men. Interhemispheric interaction, more prevalent in women, is found to enhance ones ability in such regard. We make note of this work as another way to grasp the rash male dominance of our societies and cultures as they rush to violence and war with no thought to reason or consequence.
Cook, Norman. Bihemispheric Language: How the Two Hemispheres Collaborate in the Processing of Language. Proceedings of the British Academy. 106/169, 2002. As understanding of the special functions of the left and right brain hemispheres grows in sophistication, their complementary interaction via the corpus callosum can be properly studied. The LH in general deals with auditory segmentation, denotation, close associations, literality, propositional meaning, explicit events and sequentialisation, while the RH handles intonational decoding, connotation, distance associations, metaphor, affective implications, implicit meaning (gist) and contextualization. What is observed is a left side penchant for more specific detail with the right taking a holistic survey, while in constant interplay.
Cook, Norman. Tone of Voice and Mind: The Connections between Intonation, Emotion, Cognition and Consciousness. Amsterdam: John Benjamins Publishing, 2003. A professor of informatics at Kansai University, Osaka, Japan, discusses the interplay of brain hemisphere propensities with regard to these qualities.
Crespi, Bernard. Oxytocin, Testosterone, and Human Social Cognition. Biological Reviews. Online January, 2015. The Simon Fraser University evolutionary biologist presents a novel biochemical, hormonal basis for these complementary archetypal modes. As the Abstract explains, oxytocin fosters integrative personal relations which mediate and serve group cohesion, it is a feminine “bonding” hormone. Testosterone, the male anti-thesis, is a cause of much oppositional, disruptive behavior. Once again, from another source, these ultimately gender polarities can be identified. Of course, the resolve is always a balanced marriage of yin anima and yang animus See also Life in Groups: The Roles of Oxytocin in Mammalian Sociality by Allison Anacker and Annaliese Beery in Frontiers in Behavioral Neuroscience (7/186, 2013). How then might such palliative knowledge be identified and attributed to an emergent bicameral humankind so as to heal, free, and enhance the fraught creatures it arose from?
I describe an integrative social-evolutionary model for the adaptive significance of the human oxytocinergic system. The model is based on a role for this hormone in the generation and maintenance of social familiarity and affiliation across five homologous, functionally similar, and sequentially co-opted contexts: mothers with offspring, female and male mates, kin groups, individuals with reciprocity partners, and individuals within cooperating and competing social groups defined by culture. In each situation, oxytocin motivates, mediates and rewards the cognitive and behavioural processes that underlie the formation and dynamics of a more or less stable social group, and promotes a relationship between two or more individuals. Such relationships may be positive (eliciting neurological reward, reducing anxiety and thus indicating fitness-enhancing effects), or negative (increasing anxiety and distress, and thus motivating attempts to alleviate a problematic, fitness-reducing social situation). I also present evidence that testosterone exhibits opposite effects from oxytocin on diverse aspects of cognition and behaviour, most generally by favouring self-oriented, asocial and antisocial behaviours. I apply this model for effects of oxytocin and testosterone to understanding human psychological disorders centrally involving social behaviour. (Abstract)
Crespi, Bernard and Christopher Badcock. Psychosis and Autism as Diametrical Disorders of the Social Brain. Behavioral and Brain Sciences. 31/241, 2008. Crespi is an evolutionary biologist at Simon Fraser University, while Badcock is a London School of Economics sociologist. The authors converge their respective research into a well-received synthesis which contends that these mental spectrums represent and ought to be best appreciated as polar extremes. If one may condense a rich article, they fall into archetypal categories of an attention to, or obsession with, either autistic particulate, insular detail or psychotic, manic/depressive associations. Respective genetic paternal and maternal influences can then be noted, while these typical behaviors go on to define an extreme masculine or feminine dichotomy. By virtue of such insights, along with many other contributions herein, the universal gender complements reappear, which again evoke an ever elusive middle balance. The paper merits a long quote from its abstract.
Autistic-spectrum conditions and psychotic-spectrum conditions (mainly schizophrenia, bipolar disorder, and major depression) represent two major suites of disorders of human cognition, affect, and behavior that involve altered development and function of the social brain. We describe evidence that a large set of phenotypic traits exhibit diametrically opposite phenotypes in autistic-spectrum versus psychotic-spectrum conditions, with a focus on schizophrenia. This suite of traits is inter-correlated, in that autism involves a general pattern of constrained overgrowth, whereas schizophrenia involves undergrowth. These disorders also exhibit diametric patterns for traits related to social brain development, including aspects of gaze, agency, social cognition, local versus global processing, language, and behavior. Social cognition is thus underdeveloped in autistic-spectrum conditions and hyper-developed on the psychotic spectrum.
Crespi, Bernard, et al.
Imagination in Human Social Cognition, Autism, and Psychotic-Affective Conditions.
Simon Fraser University and University of Alberta bioneuroscientists advance their insights into a psychological continuum from autistic behaviors unable to make connections to disorders of over-perceived imagery. As much research attests, autism is a male condition which fixates on separate pieces or dots without any object, or personal interrelations. At the other end, schizophrenics are known to obsess over realities not in actual existence. These states appear to exhibit directly-opposite patterns with regard to convergent versus divergent thinking, and restricted interests and insistence on sameness versus novelty, fantasy, goal-seeking in mania, and openness. (184)
Complex human social cognition has evolved in concert with risks for psychiatric disorders. Recently, autism and psychotic-affective conditions (schizophrenia, bipolar disorder, depression) have been posited as psychological ‘opposites’ with regard to social-cognitive phenotypes. Imagination, considered as ‘forming new ideas, mental images, or concepts’, represents a central facet of human social evolution and cognition. Previous studies have documented reduced imagination in autism, and increased imagination in association with psychotic-affective conditions, yet these sets of findings have yet to be considered together, or evaluated in the context of the diametric model. We first review studies of the components, manifestations, and neural correlates of imagination in autism and psychotic-affective conditions.
Crespi, Bernard, et al. Spirituality, Dimensional Autism, and Schizotypal Traits. PLoS One. March, 2019. Simon Fraser University and University of Alberta behavioral biologists consider Crespi’s research model (search) that generic autistic and psychotic states can be seen to represent diametric psychological poles of incoherent, unrelated pieces or overdrawn whole images. In this paper, such persuasions can also be seen to influence a person’s belief or lack thereof about any abiding, numinous meaning.
The relationships of spirituality with human social cognition, as exemplified in autism spectrum and schizophrenia spectrum cognitive variation, remain largely unstudied. We quantified non-clinical levels of autism spectrum and schizotypal spectrum traits and dimensions of spirituality in a large sample of undergraduate students. We tested the hypothesis, based on the diametrical model of autism and psychosis, that autism should be negatively associated, and schizotypal traits should be positively associated, with spirituality. First, in support of the diametric model, total Spirituality score was negatively correlated with Autism Quotient score, and positively correlated with Positive Schizotypal traits, as predicted. Second, these associations were driven by opposite patterns regarding the Search for Meaning Spirituality subscale. Third, Belief in God was correlated with Positive Schizotypal traits, but uncorrelated with autism traits. The opposite findings for Search for Meaning can be interpreted by cognitive models for understanding autism in terms of weak central coherence, and Positive Schizotypal traits in terms of enhanced salience. (Abstract excerpt)
Darlington, Cynthia. The Female Brain. Boca Raton: CRC Press, 2009. In this second edition, the University of Otago, New Zealand, neurophysiologist updates the latest findings over cerebral gender distinctions. The chapter on Laterality is typically succinct and once again confirms that men quite favor the analytical left side, while women’s brains have a faster “interhemispheric transfer time” which results in a more symmetrical thought process. After some four decades of research since Roger Sperry’s breakthrough, we can now know that we indeedhave an archetypal complementarity, a micro yin/yang universe, in our heads. And it begs that our present global mentation, re the recent Copenhagen debacle, seems male half brained in the extreme, in such need of a worldwide whole hemisphere balance, i.e. a woman’s wisdom.
Davis, Simon, et al. Complementary Topology of Maintenance and Manipulation Brain Networks in Working Memory. Nature Scientific Reports. 8/17827, 2018. As the Abstract describes, by way of sophisticated MRI imaging studies, thirteen Duke University neurologists and cognitive psychologists achieve even more evidence that our brains require and avail a best balance of iconic conservative and creative modes of behavior.
Working memory (WM) is assumed to consist of a process that sustains memory representations in an active state (maintenance) and a process that operates on these activated representations (manipulation). We examined evidence for two distinct, concurrent cognitive functions supporting maintenance and manipulation abilities by testing brain activity as participants performed a WM alphabetization task. Maintenance was investigated by varying the number of letters held in WM and manipulation by varying the number of moves required to sort the list alphabetically. We found that both maintenance and manipulation demand had significant effects on behavior that were associated with different cortical regions: maintenance was associated with bilateral prefrontal and left parietal cortex, and manipulation with right parietal activity, a link that is consistent with the role of parietal cortex in symbolic computations. Both structural and functional architecture of these systems suggested that these cognitive functions are supported by two dissociable brain networks. (Abstract)