VI. Life’s Cerebral Cognizance Becomes More Complex, Smarter, Informed, Proactive, Self-Aware

2. Laterality: A Bicameral Brain Emerges with the Nested Scales

Schnell, Alexandra, et al. Lateralization of Eye Use in Cuttlefish: Opposite Direction for Anti-Predatory and Predatory Behaviors. Frontiers in Physiology. December, 2016. Normandie University, Caen and Woods Hole Marine Biological Laboratory researchers find the same cross-hemisphere referral of left finer focus and right wide view in this Cephalopoda class as human beings do. Again these common, bicameral modes are found to hold across every animal realm. (Their unified reciprocity could well serve as a natural model for bipartisan politics.)

Vertebrates with laterally placed eyes typically exhibit preferential eye use for ecological activities such as scanning for predators or prey. Processing visual information predominately through the left or right visual field has been associated with specialized function of the left and right brain. Lateralized vertebrates often share a general pattern of lateralized brain function at the population level, whereby the left hemisphere controls routine behaviors and the right hemisphere controls emergency responses. (Abstract excerpt)

Seoane, Luis. Evolutionary paths to lateralization of complex brain functions. arXiv:2112.00221. A Centro Nacional de Biotecnologıa (CSIC), Madrid and MIT biologist (search) propose novel theoretical reasons why life’s cerebral encephalization arrayed itself with a double faculty where each side contributes vital halves half of the thought process.

At large, most animal brains present two mirror-symmetric sides; but closer views reveal a range of consistent asymmetries. The complexity of a computational task might play a role in breaking bilaterally symmetric circuits into fully lateralized ones; yet a mathematical theory of how this might work is missing. Here we provide an example from basic assumptions and extend it to biologically and computationally scenarios. The implications of these results for evolution, development, and rehabilitation of damaged or aged brains is discussed. (Abstract)

Tommasi, Luca. Mechanisms and Functions of Brain and Behavioural Asymmetries. Philosophical Transactions of the Royal Society B. 364/855, 2009. An introduction to this dedicated issue whose papers could represent a synthesis of research areas not possible earlier. For some years the study of brain hemisphere attributes with regard to humans or non-humans proceeded somewhat on their own. Sufficient findings are now in place to join a deep evolutionary continuity with the generic propensities of the left side for close detail, and the right side for integral image. A synoptic contribution by Michael Corballis is noted above.

Asymmetries in behavior exhibited by birds, fishes, amphibians, rodents and primates have since provided a strong argument for functional lateralization being a universal and evolutionarily ancient trait of the vertebrate brain. (856)

Vallortigara, Giorgio and Lesley Rogers. A Function for the Bicameral Mind. Cortex. Online December, 2019. The University of Trento, Italy and University of New England, Australia senior scholars continue to advance understandings of the pervasive presence and advantages across all phyla of dual brain hemispheres with opposite but complementary discrete particle (seed, me) or whole image (relations, We) attributes. This deep evolutionary benefit is most manifest in human cerebral activity, but we seem to work against this reciprocity as evident by local and global political conflicts. (Here is an example of a worldwide scientific discovery about a vital neural anatomy across animal kingdoms which a male (dots only) academia is unable to comprehend.)

A lateralized brain, in which each hemisphere processes sensory inputs and carries them out in different ways, is common in vertebrates, and it now reported for invertebrates too. As shown in many animal species, having a lateralized brain can enhance the capacity to perform two tasks at the same time. Why is this the case? Not only humans, but also most non-human animals, show a similar pattern of directional asymmetry. For instance, from fish to mammals most individuals react faster when a predator approaches from their left side. Using mathematical theory of games, it has been argued that the population structure of lateralization may result from the type of interactions asymmetric organisms face with each other. (Abstract excerpt)

Vallortigara, Giorgio and Lesley Rogers. Survival with an Asymmetrical Brain: Advantages and Disadvantages of Cerebral Lateralization. Behavioral and Brain Sciences. 28/4, 2005. Over the past decade, many studies have quantified that a bilateral brain with complementary hemispheric functions, once thought to be uniquely human, is present throughout the animal kingdom. On an evolutionary scale, this archetypal anatomy can be traced from primates to birds, rodents, reptiles, amphibians and fish. In general, the left brain is associated with the right visual field, and vice versa. This article notes a liability for creatures if predators approach from a side whose hemisphere is less apt in their notice. But as a whole, with a typical left brain for fine local discrimination (seeds among pebbles) and the right for spatial perception and emotions, it is of advantage to have this division of cognitive effort.

Vallortigara, Giorgio, et al. Separate Geometric and Non-Geometric Modules for Spatial Reorientation. Journal of Cognitive Neuroscience. 16/3, 2004. From the Universities of Trieste and Padua, a contribution that asymmetrical, hemispheric cerebral faculties can be found amongst primates, mammals, birds, amphibians, and fish. In this case, studies of the chicken avian brain typically find a characteristic left side penchant for detail with a right half attention to contextual wholes. Metazoan evolution then seems to proceed by the merger of initially separate modules toward a manifest integral synthesis in humans.

The results suggest separate mechanisms for dealing with spatial reorientation problems, with the right hemisphere taking charge of large-scale geometry of the environment and with both hemispheres taking charge of local, non-geometric cues when available in isolation, but with a predominance of the left hemisphere when competition between geometric and non-geometric information occurs. (390)

Vauclair, Jacques, et al. The Study of Hemispheric Specialization for Categorical and Coordinate Spatial Relations in Animals. Neuropsychologia. 44/1524, 2006. This extensive article sorts out several prior studies of brain hemisphere attributes in mammals and birds to arrive at a general correlation of fine focus, particular attention with the left side and a broader, more holistic survey with the right brain. As a result, these qualities or functions, most pronounced in humans, are found to have a long evolutionary heritage. Not quantified a decade ago, here is still another novel indicator of a universal creative complementarity.

The left hemisphere seems to focus on smaller portions of a pattern, does not care of the configuration of these portions, and is rather effective in acquiring a category that can be transferred to novel pictures. Contrary, the right hemisphere is more globally driven, uses relational information and is less effective in transferring to new exemplars. (1530) Typically, the RH is faster and more accurate to identify global components of the input and the LH is faster and more accurate to identify local components. (1531) ….a local- versus global distinction that results from left- and right-hemispheric mechanisms, respectively, can be found in nonhuman primates and pigeons. (1531) Thus, an asymmetric local/global distinction could be a very old feature of vertebrate brains. (1531)

Yamazaki, Y, et al. Lateralized Cognition: Asymmetrical and Complementary Strategies of Pigeons. Cognition. 104/2, 2007. Over the last decade researchers have quantified that our human brain bicameral attributes of a left particulate focus and right integral context, now agreed upon, similarly occur across the animal kingdoms. This subject article explains how pigeons discriminate and observe their environment in such like manner. Now from this vantage, a salient discovery ought to be noted. A cerebral complementarity is found to distinguish and emerge with creaturely evolution, coming to full capacity in reflective persons. This achievement further reveals the manifest presence of a universal archetypal reciprocity.

The results suggest that the left hemisphere employs a category strategy and concentrates on local features, while the right hemisphere uses an exemplary strategy and relies on configuration. These cognitive dichotomies of the cerebral hemispheres are largely shared by humans, suggesting that lateralized cognitive systems already defined the neural architecture of the common ancestor of birds and mammals. (315-316) On the basis of these findings, it is likely that the RE/LH (right eye) analyzes objects in detail, whereas the LE/RH attends to broader parts of the stimuli as well as to their configuration. (318)

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