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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>AIC</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>A Critical Look Into Cognitively-Inspired Artificial Intelligence</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sara Mahmoud</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alice Plebe</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Skövde</institution>
          ,
          <addr-line>Skövde</addr-line>
          ,
          <country country="SE">Sweden</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Trento</institution>
          ,
          <addr-line>Trento</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2022</year>
      </pub-date>
      <volume>8</volume>
      <fpage>0000</fpage>
      <lpage>0003</lpage>
      <abstract>
        <p>Nature has been a great source of inspiration for many inventions and theories. One of the major benefits for this inspiration is perceiving the impossible as possible. The inception of the AI field was no exception with cognitively-inspired approaches with a dream of having an intelligent system that thinks as a human. However, this journey of human intelligence into machine intelligence has been rough and more challenging that resulted in the separation of AI from cognitive studies. In this article, we highlight the main challenges and opportunities for cognitive inspiration for AI development. We then break down the source of inspiration into four abstraction levels in which the researcher may place an inspiration from. These levels then contribute into three main stages for modeling the AI system. The two dimensional mapping from cognitive levels into modeling stages and the relation between them aims to assist the process of cognitively-inspired approaches.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Cognitively-inspired systems</kwd>
        <kwd>cognitive abstraction levels</kwd>
        <kwd>Artificial Intelligence</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Computer systems and software can be said to evolve through two main approaches;
conventional and bio-inspired [1]. The former approach develops systems through the engineering
methodology of system development, while the latter approach borrows inspiration from nature
and applies it with the conventional approach. Cognition has been one of the origin sources
for inspiration for developing artificial intelligence systems with an idealistic goal for reaching
general intelligence [2] since the development of the Turing machine and setting the Turing
test for determining the machine’s intelligence. While the 1956 Dartmouth Summer School
on Artificial Intelligence is considered the starting point of developing AI to simulate human
intelligence presented by top researchers at the time [3].</p>
      <p>Many conventional approaches and mathematical formulas were initiated based on theories
and models of cognition and inspiration at the early stage of AI such as neural networks,
natural language processing, recommender systems, deep learning and others. However, the
development of these theories and applications evolved in a conventional progression method
with less involvement from its source of inspiration. As a result, the association between AI
techniques and cognitive inspiration started to fade gradually. AI has since become a heavily
computational with the conventional approach to develop applications that does not require
a cognitive equivalence. With this separation, less focus has been placed for developing clear
methodologies for combining conventional approaches with bio-inspired ones [1]. Besides, the
advantages of this combination started to blur in researchers’ view.</p>
      <sec id="sec-1-1">
        <title>1.1. From challenges to opportunities for cognitively inspired systems</title>
        <p>Developing cognitively inspired systems is a challenging journey. It requires first an
understanding of the underlying cognitive science theories. Cognitive science was originally formulated as
a synergy between the fields of psychology, linguistics, computer science, philosophy,
neuroscience, and anthropology [4].</p>
        <p>Biological inspiration further requires defining the degree of faithfulness to what the scientist
will replicate from the biological system. It also requires flexibility in adjusting the model
from a description of a biological system to what is suitable for an artificial agent [ 5]. This
often involves a translation into a more formal model description [6]. There is still a lack of
clear methodology for transferring a biological system into a technological artifact, or phrased
diferently, we need a bridge between the bio-inspired approach and the conventional approach
[7].</p>
        <p>Despite these challenges, taking the route of bio-inspired approach opens opportunities that
may be dificult to achieve with the conventional one. Among all the gains, taking inspiration
from nature allows the researcher to be a pioneer in leading ideas of development. The initiation
of the concepts of flying was inspired and tested by Ibn Firnas in the 9th century by observing
birds flying [ 8] and set the mathematical foundation for flying which highly contributed to the
invention of airplanes nowadays. Another example, at the same time period, Ibn AlHaytham
studied the anatomy of the human’s eye and set the foundation of capturing an image through
a small hole in a dark room projecting the image into the wall called Qoumra. This theory was
the groundwork for the invention of cameras presently [9].</p>
        <p>In the field of AI, the impact of artificial neural networks and modern day deep learning can
not be overstated [10], and it remains an excellent example of a bio-inspired technology. The
origin of this technique is based on the brain neural networks forming multi-layers of neurons
feeding into each other that collectively process the data and perform advanced cognitive tasks.</p>
      </sec>
      <sec id="sec-1-2">
        <title>1.2. Levels and categorization</title>
        <p>For the bio-inspired approach, the researcher examines the applicable cognitive theory and
models. While an abundance of the literature discusses conceptual descriptions of what a
cognitive system should do, less is discussed on how this translates into a formal model for an
artificial system. This causes confusion for the researcher for how to take the inspiration.</p>
        <p>One of the early works for clarifying the development of cognitive systems was by Marr
and Poggio [11] who argue that a complex systems, especially the ones inspired by cognition,
should be understood at three main and independent levels; the computation that describes the
task, the algorithm that specifies how the task is implemented and the hardware that executes
the implementation and data.</p>
        <p>Newell discussed another perspective of cognitive operation levels that is based on timescale
[12]. This includes biological (such as the neural spike) that takes nano to milliseconds, cognitive
operations (that includes the cognitive architecture for tasks as grasping objects) that takes
tenth of a second to less that ten seconds, and rational operation that requires reasoning (such as
doing the laundry) takes few seconds to minutes. Finally, the social behaviors (with interactions)
that may take hours to days.</p>
        <p>An extended categorization for Newell’s levels of cognition by timescale is presented by Lieto
[13]. In this work, Lieto presents the relation between cognitive systems and AI historically
and shows examples from the literature for cognitively inspired work as well as a view for the
future relation in terms of a roadmap.</p>
        <p>From a cognitive modeling point of view, Guest and Martin [14] propose a framework of six
layers for building computational models for psychological research in which outputs each layer
is fed to the following one and verifies the layer above. The layers top-down are; framework,
theory, specification, implementation, hypothesis and data.</p>
        <p>Lieder &amp; Grifiths [ 15] discussed the rationality theory of human cognition as a higher level of
psychological theory in a computational level (in Marr’s categorization) and then they presented
a resource-rational analysis as a methodology for connecting rational human cognition with AI
and neuroscience.</p>
        <p>Here, we propose a description of the transitioning from cognitive studies to AI systems as
a two dimensional mapping (see Table 1). The vertical dimension defines levels of cognitive
complexity that is the source of inspiration. The horizontal dimension describes the stages for
modeling and developing the system.</p>
        <p>The dimension of cognitive complexity refers to the complexity of the system that inspires the
researcher. We categorize cognitive complexity in four levels, from least cognitive complexity;
the cellular, the architecture, the functional and the behavioral.</p>
        <p>Second, the modeling of a computational cognitive system is carried out in multiple stages as
described by Guest and Martin [14] and Marr and Poggio [11]. Here we determine three main
stages in which the inspiration would mostly afect. Starting from the theoretical stage that
(framework and theory in Guest and Martin). This also includes the computational level for
describing the task and the theoretical description in the algorithmic level in Marr’s
categorization. Then, this feeds into the implementation stage (specification and implementation in
Guest and Martin) including the algorithm description in Marr’s categorization. Finally, the
data level includes the representation and source of the data. This includes the input/output
representation from the algorithm level and the physical representation in the hardware level
in Marr’s categorization.</p>
        <p>
          Table 1 shows the results of inspiration development to two dimensions. Inspiration at the
cellular level (A) refers to the smallest biological component for cognition such as the neuron
as the least cognitive level. (
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) This inspiration feeds into the theories such as artificial neural
networks of spiking neurons [16] and learning by spike-timing dependent plasticity [17, 18].
(
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) Inspiration feeds into implementation with equation formulation for the spiking neurons
such as Bayesian computation by spike-timing dependent plasticity [19] and deep convolutional
models with spiking neurons [20]. (
          <xref ref-type="bibr" rid="ref3">3</xref>
          ) In the data stage, inspiration helps in formation and
processing on low cellular level signals such as neuromorphic cameras [21].
        </p>
        <p>
          On the architectural level (B) the inspiration broadens the ability to build more complex
systems with large architectures including components. (
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) This level feeds into theories such
as neural semantic pointers [22], computational maps inspired by the visual cortex [23] and
convergence-divergence zones [24]. (
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) This is reflected in implementation such as Semantic
Pointer Architecture Unified Network (SPAUN) [ 25] and highly successful object recognition
deep convolutional models [26]. (
          <xref ref-type="bibr" rid="ref3">3</xref>
          ) Besides, it inspires researchers on how the data flows
internally from the perception system to the rest of the processing components such as in visual
cortex sparse representations [27] and Cortical magnification [28].
        </p>
        <p>
          With the functional level (C) inspiration, the researcher is able to look at more complex
systems with mental tasks such as perception and decision making. At this level, the physical
body and the interaction with the external world is highly involved. (
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) In the theory stage
this inspires theories for interacting with the environment such as Local, error-driven and
associative, biologically realistic algorithm (LEABRA) [29] and Reinforcement learning [30].
(
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) The implementation of mental tasks inspires work as AlphaGo [31] and AlphaZero [32]
that are deep implementations of reinforcement learning achieving superhuman performance
in challenging combinatorial games and deep reinforcement learning for robotic dexterous
manipulations [33]. (
          <xref ref-type="bibr" rid="ref3">3</xref>
          ) On the data level it inspires the flow of the data between the system
and the environment as well as the form of data for interaction and decision making such as
Human-like system data parameters [34].
        </p>
        <p>
          At the behavioral level (D), the scientist studies human cognition as examined by an
external observer such as learning by demonstration. (
          <xref ref-type="bibr" rid="ref1">1</xref>
          ) In theory inspiration this includes
resource-rational analysis [15], behavioral cloning [35], apprenticeship learning [36] and
inverse reinforcement learning [37]. (
          <xref ref-type="bibr" rid="ref2">2</xref>
          ) Behavior level inspiration brings many implementation
inspiration such as end-to-end deep learning networks [38] and robots by imitation [39]. (
          <xref ref-type="bibr" rid="ref3">3</xref>
          ) On
the data stage, this level defines the data required and used for behavior implementation such
as Behavioral cloning of human driving behaviors [40, 41]
        </p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2. Conclusion</title>
      <p>Despite the opportunities gained by bio-inspired approaches for developing intelligent systems,
it has been a challenge for researchers to translate between the two fields. In this short paper
we briefly discusses the challenges and opportunities for cognitively inspired systems and a
two dimensional mapping of cognitive inspiration to computation modeling stages.</p>
      <p>We categorize cognitive complexities from the least level of cellular level cognition to
architectural including brain components, then functional in which cognitive abilities are required
for interaction with the environment, and behavioural cognition that includes imitation and
social abilities.</p>
      <p>The researcher then needs to understand the stages of modeling and developing a cognitive
system. This includes defining the theory of the model and the required formal models and
equation for implementation as well as the data and hardware for the system.</p>
      <p>This work is in progress for further investigation of modeling a concrete artificial system
based on the bio-inspired approach. The future work includes the examination of other factors
for inspiration such as the degree of loyalty in copying the biological cognition. Inspiration and
cognitive modeling requires a degree of adjustment from biological system modeling to formal
modeling. While the exact creation of cognitive modeling could be desired but impossible, a
loose copying could be argued not to be bio-inspired or mimicking the biological cognition.
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