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

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

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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