Monday, August 19, 2013

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Supports for the Hypothesis of Higher Brains Re-iterating the Functions of the Lower Ones - implies that the function of the higher ones could be induced by understanding the functions of the lower ones and extending them

It's about proposals that I've initially published there:

Wednesday, March 9, 2011
Proposal for Directed/Guided Evolution of a Cognitive Module/Algorithm by Step-by-Step Modification of a Basic One - from Archicortex to Neocortex

And later in a comment after:

Tuesday, October 18, 2011
Rationalization and Confusions Caused by High Level Generalizations and the Feedforward-Feedback Imbalance in Brain and Generalization Hierarchies

From that article:

-- CITE from Nature Neuroscience BEGIN --

"Surprise! A unifying model of dorsal anterior cingulate function?"
Tobias Egner
Nature Neuroscience 14, 1219–1220 (2011) doi:10.1038/nn.2932
Published online 27 September 2011

Few brain regions' functions have been debated as intensely as those of the dorsal anterior cingulate cortex. A computational model now suggests that seemingly diverse cingulate responses may be explained by a single construct, 'negative surprise', which occurs when actions do not produce the expected outcome.

-- END --

([About] My hypothesis from the "Guided evolution of ..." - newer brains [regarding the Triune theory] actually do the older brains' job and are supposed to have a lot of functional similarities. Newer brains intrinsically are "tweaks" of old ones, have significantly more computational resources/room for scaling complexity and extend older brain design to allow for higher resolution and scope.)

An opinion of B.K. about that, from the comments:

"B: OK, reacting to "negative surprise" really means more planning. That's what prefrontal cortex does too, & the difference might be in temporal scope, which would be person & situation -specific."

Another paper which in my opinion suggests that [dorsal] anterior cingulate's functions are similar to the functions of the prefrontal cortex (PFC):

Nature. 2012 Aug 9;488(7410):218-21. doi: 10.1038/nature11239.
Human dorsal anterior cingulate cortex neurons mediate ongoing behavioural adaptation.

Sheth SA, Mian MK, Patel SR, Asaad WF, Williams ZM, Dougherty DD, Bush G, Eskandar EN.
Source ... Nayef Al-Rodhan Laboratories, Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.

(...) The dorsal anterior cingulate cortex (dACC), which lies on the medial surface of the frontal lobes, is important in regulating cognitive control. Hypotheses about its function include guiding reward-based decision making, monitoring for conflict between competing responses and predicting task difficulty. (...) Our results demonstrate that the dACC provides a continuously updated prediction of expected cognitive demand to optimize future behavioural responses.

Yet another article, that suggests that the posterior cingulate gyrus has functional similarities to neocortex areas which are more closer to some of the sensory cortices, the visual and somatosensory (postcentral gyrus), which are located posterior as well:

Neural representation of abstract and concrete concepts: a meta-analysis of neuroimaging studies


(...) Abstract concepts elicit greater activity in the inferior frontal gyrus and middle temporal gyrus compared to concrete concepts, while concrete concepts elicit greater activity in the posterior cingulate, precuneus, fusiform gyrus, and parahippocampal gyrus compared to abstract concepts. These results suggest greater engagement of the verbal system for processing of abstract concepts and greater engagement of the perceptual system for processing of concrete concepts, likely via mental imagery.

-- END --

Regarding abstract concepts and cognition - Broca's Area, whose impairment causes non-fluent aphasia, is located in the inferior frontal gyrus.
Notice also the parahippocampal gyrus and the fusiform gyrus (the "face cells").

Abstract concepts are related to natural language, which in humans usually is introduced, trained, exercised etc. through speech. That involves a location which is both: high enough (gets the audio and other multi-modal input processed and integrated), and near enough M1 and other motor areas, the tongue, mouth etc. neurotoppical mappings:

and to other executive function areas - such as the orbifrontal cortex, - which are specific by their broad connections to the entire brain, and that they are highly affected by the reward system  (dopamine-related), which is about guiding behavior and decision making.

Faces are not that abstract. There are words for "square face", "triangle face" etc., but recognition of specific faces require some more detail, that has to be still in the system when processing - it happens lower in the chain. Another simpler clue that it's supposed to be so is the fact that infants recognize the face of their mother (to fake artificial faces, 2D pictures or other people) as early as the first year.

The parahippocampal gyrus is near the hippocampus and connected to it, as its name suggests, and the hippocampus is the human homologue of the archicortex, the oldest brain in Triune theory.

The bottom line of my hypothesis and propsal is that the functions of the higher brains (in the Triune theory system: Neocortex - Limbic System - Reptilian complex) could be induced by understanding the functions of the lower ones from the chain, which are supposed to be simpler, more transparent and closer to direct sensory processing, and then extending their scope - computational resources, time-span, resolution, memory capacity, generalization steps.

Also vice verse - understanding the higher cognition and gradually simplifying it, going from abstract functions and finding more specific and more "localized", specialized, smaller span/area of application (as inputs and possible reactions); more direct, undistilled processing, should eventually lead to reducing to the functions of the lower brains - the whole systems - or homologous higher-lower areas - such as anterior cingulate to prefrontal cortex.

Of course, this is a general hypothesis, it has to get more specific.


Regardin IFG, see also:

Neuroimage. 2010 Apr 15;50(3):1313-9. doi: 10.1016/j.neuroimage.2009.12.109. Epub 2010 Jan 4.

The role of the right inferior frontal gyrus: inhibition and attentional control.
Hampshire A, Chamberlain SR, Monti MM, Duncan J, Owen AM. Source
Medical Research Council Cognition and Brain Sciences Unit, Cambridge, UK.

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