*E-mail: zhcho36@gmail.com
Human Cognition and Language Processing with Neural-Lexicon
Hypothesis
Zang-Hee Cho1†, Sun-Ha Paek 2, Young-Bo Kim 3, Taigyoun Cho4, Hyejin Jeong1, Haigun Lee 5†
1Neuroscience Convergence Center, Institute of Green Manufacturing Technology, Korea University, Seoul, South Korea
2Department of Neurosurgery, School of Medicine, Seoul National University, Seoul, South Korea
3Department of Neurosurgery, School of Medicine, Gachon University, Incheon, South Korea
4Department of Industrial Design, Hong Ik University, Seoul, South Korea
5Department of Material Science, Institute of Green Manufacturing Technology, Korea University, Seoul, South Korea
†These authors contributed equally to Co-Corresponding author
ABSTRACT
Cognition and language seem closely related to the human cognitive process, although they have not been studied
and investigated in detail. Our brain is too complex to fully comprehend the structures and connectivity, as well
as its functions, with the currently available technology such as electro-encephalography, positron emission
tomography, or functional magnetic resonance imaging, and neurobiological data. Therefore, the exploration of
neurobiological processes, such as cognition, requires substantially more related evidences, especially from in-
vivo human experiments. Cognition and language are of inter-disciplinary nature and additional methodological
support is needed from other disciplines, such as deep learning in the field of artificial intelligence, for example.
In this paper, we have attempted to explain the neural mechanisms underlying “cognition and language processing”
or “cognition or thinking” using a novel neural network model with several newly emerging developments such
as neuronal resonance, in-vivo human fiber tractography or connectivity data, Engram and Hebbian hypothesis,
human memory formation in the high brain areas, deep learning, and more recently developed neural memory
concepts, the neural lexicon. The neural lexicon is developed via language by repeated exposure to the neural
system, similar to multilayer signal processing in deep learning. We have derived a neural model to explain how
human “cognition and language processing” or “cognition and thinking” works, with a focus on language, a
universal medium of the human society. Although the proposed hypothesis is not fully based on experimental
evidences, a substantial portion of the observations in this study is directly and indirectly supported by recent
experimental findings and the theoretical bases of deep learning research.
Key words: Neural Network Modeling, Neural-Lexicon, Neural Resonance, Cognition and Language
Processing, Cognition and Thinking
1. INTRODUCTION
Human cognition and language are the two most
difficult subjects due to their wide variely and the
lack of evidence especially on their neural basis.
Nevertheless, it is worthwhile to study based on
contenparary neuroscience perspective with the
modern logic behind deep learning.
For this study, we have chosen “cognition” and
“language,” or slightly differently “cognition” and
“thinking,” as the central topics. We attempted to
answer the questions from neuroscience
perspectives while leveraging AI tools, specifically
deep learning with multiple signal processing layers,
which we modified with neural bases and termed as
neural lexicons. Neural lexicons are memory units
believed to be developed via languages and other
related neuroscience developments such as newly
developed fiber tractography or connectivity data
neuronal Resonance, Hebbian neural processes, or
the Engram1–6. Language, in particular, appears to
play a major role and is a unique human property
with which we have postulated and developed neural
lexicons, which are similar to the signal processing
layers in deep learning7–15. A general sketch of the
proposed neural pathways or the network for
“cognition and language” or “cognition and thinking”
is provided in Fig. 1, where three neural Lexicons
and two memory units are shown together with
connecting fibers from the sensory areas to the
motor areas. We have provided details of the neural
circuit shown in Fig. 1 subsequently.
We begin with the basic neuronal process as shown
in Fig. 2. With this process, a conceptual neuronal
activity involving previously excited and newly
excited neurons, especially the neurons that are
excited at the same time by the external stimulation,
such as the Hebbian neurons, seem to play
significant a role in the early stages of the neural
signal processing of the sensory cortex.
As a simplified example, the neuronal signal, which
we coined as the “sensogram” is assumed to
represent the total number of activated neurons at a
given moment, which is shown as (see also Fig. 2(a)),