Cognitive Science

Question 1

What is phrenology?

Answer 1

Phrenology is a pseudoscience which was founded at the end of the 18th century by Franz Joseph Gall.

It tried to describe the mind based on assumptions on the anatomical structure of the brain. The size of a brain region was to indicate how much the corresponding faculty contributes to a person’s character.

Question 2

What is cytoarchitectonics?

Answer 2

Cytoarchitectonics is the study of the cellular composition of the brain’s tissues under the microscope.

Question 3

What are the Brodman areas?

Answer 3

52 regions of the cerebral cortex as divided by German neurologist Korbinian Brodman in 1907 based on cytoarchitectonic properties.

Brodman claimed that the individual regions correspond to specific functions.

Question 4

What is neuroimaging?

Answer 4

The use of various techniques to image the structure and function of the brain.

Question 5

What is the difference between structural and functional neuoimaging?

Answer 5

Structural imaging deals with the structure of the brain and the diagnosis of large scale intracranial (within the skull) disease (such as a tumor) and injury.

Functional imaging is centered on revealing physiological activities, i.e. the function of the brain.

Question 6

What are two types of structural neuroimaging?

Answer 6

• Magnetic Resonance Imaging (MRI)

- Diffusion Tensor Imaging (DTI)

Question 7

What is MRI?

Answer 7

Magnetic Resonance Imaging (MRI) is a non-invasive method to imagine the anatomic structure of tissue in vivo. Active sensing method based on the magnetic properties of hydrogen atoms that dissipate energy differently depending on the surrounding tissue. Does not use radiation compared to CT (computed tomography) scan.

Question 8

What is DTI?

Answer 8

Diffusion Tensor Imaging (DTI) is an extension of MRI that measures the diffusion movement of water molecules and can detect nerve fibres.

Question 9

What are five types of functional neuroimaging?

Answer 9

• Electroencephalography (EEG)
• Magnetoencephalography (MEG)
• Positron Emission Tomography (PET)
• Single-Photon Emission Computer Tomography (SPECT)
• Functional MRI (fMRI)

Question 10

What is EEG?

Answer 10

Electroencephalography (EEG) is a non-invasive method to record electrical activity of the brain. Electrodes placed on the skill measure the electrical potentials resulting from neural activity.

encephalon lat. brain

Question 11

What is MEG?

Answer 11

Magnetoencephalography (MEG) is a non-invasive method to record magnetic fields produced by electrical currents in the brain using a helmet-shaped device.

Question 12

What are PET and SPECT?

Answer 12

Positron emission tomography (PET) uses radioactive substances (i.e. requires medication) to visualize and measure metabolic processes in the body. Brain activity is monitored implicitly by observing the regional cerebral blood flow.

Single-Photon Emission Computer Tomography
(SPECT) is cheaper and more detailled.

Question 13

What is fMRI?

Answer 13

Functional MRI (fMRI) is an extension of MRI that visualizes changes of the blood oxygen level caused by brain activity.

Question 14

What is haptic fMRI?

Answer 14

Haptic fMRI augments fMRI with a haptic (relating to the sense of touch) input device:

• test person in MRI looks at virtual objects on a screen
• haptic input device enables interaction with the objects
• brain activity is monitored via fMRI

Question 15

How can cognitive systems and functions be modeled at different degrees of biological realism?

Answer 15

• computational models implement cognitive functions solely based on a functional view of the system without any reference to biology
• bio-inspired models implement cognitive functions by replicating biology
• hybrid models combine both.

biological inspiration vs. level of abstraction

Question 16

What are the two explanations for cognitive behavior?

Answer 16

• ultimate explanation: why does it exist?
• proximate explanation: how does it work?

The types are complementary and the distinction is critical to evolutionary explanation.

Consequence: to successfully develop a cognitive system requires that the implementation of cognitive functions with ultimate explanations match the system’s specific working environment.

Question 17

What are the three levels of abstraction in cognitive modeling?

Answer 17

• computational theory: what to compute? strategy?
• representation and algorithms: how to realize the computations?
• hardware implementation: how to physically implement the representations and algorithms?

Depending on the modeling paradigm, the levels are loosely or tightly coupled.

Question 18

What are two paradigms of cognitive modeling?

[IMPORTANT]

Answer 18

• Cognitivist systems: cognition is a form of computation. Cognitive functions are modeled as working computer programs
• Emergent systems: cognition is a continuous self-organizing process driven by the interaction between the agent and its environment
• -Enactive/Connectionist/Dynamical approaches

Question 19

What is the central hypothesis of Cognitivsm?

Answer 19

Cognition is achieved by operations on symbols that have a one-to-one correspondence to real-world actions and objects.

Over time, the focus of AI shifted to purely computational techniques. Artificial Intelligence with focus on cognition is today called Artificial General Intelligence.

Cognitivist systems: cognition is a form of computation. Cognitive functions are modeled as working computer programs

Question 20

What is Artificial General Intelligence?

Answer 20

Artificial Intelligence with focus on cognition. (Strong / Full AI)

Question 21

What questions does the Philosophy of Mind address?

Answer 21

What is the relation between the mind and the body? (mind-body problem)

• What is the basic nature of mental phenomena such as thought, perception, etc.?
• How can qualia (subjective conscious experiences) be explained?

Question 22

What are qualia?

Answer 22

Qualia are subjective, conscious experiences.

Question 23

What are the two central schools of thought on the Mind-Body Problem?

Answer 23

• Dualism

- Monism

Question 24

What is substance dualism?

Answer 24

Substance dualism postulates the mental can exist outside of the body, and the body cannot think.

Question 25

What is Monism?

Answer 25

There is only once substance; mental states = physical states.

Question 26

What is the Computational Theory of Mind?

Answer 26

The Computational Theory of Mind (CTM) holds that the mind is a digital computer; cognition and consciousness are a form of computation.

Computers are viewed as proof that purely syntactic operations can express the causality in the semantics of cognitive processes. Cognition can therefore be implemented in a purely physical system.

Question 27

What is a Physical Symbol System (PSS)?

Answer 27

A physical symbol system takes physical patterns (symbols), combining them into expressions and processing them to produce new expressions.

Question 28

What is the Physical Symbol System Hypothesis?

Answer 28

A physical symbol system has the necessary and sufficient means for general intelligent action.

-> Every cognitive system is a physical symbol system.

Question 29

What is the Heuristic Search Hypothesis?

Answer 29

Cognition is reflected in an intelligent search strategy that finds a solution without exhaustive brute-force search.

Physical-symbol systems solve problems by search (generating and progressively modifying symbol structures until it produces a solution structure).

Question 30

What is Rationality?

Answer 30

Rationality means that an agent acts in a sensible and purposeful way to achieve its goals.

Question 31

What is the difference between optimal and bounded rationality?

Answer 31

Optimal rationality: an ideal agent, which given its belief-desire system, optimizes its choices (not feasible in reality)

Bounded Rationality: rationality exhibited by decision makers of limited abilities.

Question 32

What is emergence?

Answer 32

Emergence is the rise of a system that cannot be predicted or explained from antecedent conditions.

Emergence occurs when an entity is observed to have properties its parts do not have on their own. These properties or behaviors emerge only when the parts interact in a wider whole.

Question 33

What are Connectionist Emergent Systems?

Answer 33

Connectionist Emergent Systems model cognition based on networks of interconnected computational units.

Cognitive processing in these networks is distributed, parallel, and based on statistical properties instead of formal rules.

Main Components:

• simple elements called units
• equations that determine an activation value for each unit at each point in time
• weighted connections between units

Knowledge is stored in the connection weights.

Most prominent class of connectionist systems: neural networks.

Question 34

What are Enactive Emergent Systems?

Answer 34

An enactive emergent system develops its own understanding of the world around it through its interactions with the environment.

Enaction is governed by two key mechanisms:

• Phylogeny: interactions are structurally determined by the innate embodied physical and cognitive capabilities
• Ontogeny: the system is structurally coupled with the environment

Question 35

What are Dynamical Emergent Systems?

Answer 35

Dynamical emergent models of cognitive systems are based on time-dependent differential equations that allow for compact representation of complex system behavior and the application of analysis methods from dynamical systems theory.

Main properties:

• dissipation: number of reachable states reduces over time
• non-equilibrium system: stable function requires an external energy supply
• non-linearity: complex behavior can emerge from a small set of state parameters
• collective variables: the system is represented by a small set of state variables

Question 36

What are two hypotheses on Physical Symbol Systems?

Answer 36

• Physical Symbol System Hypothesis: every cognitive system is a physical symbol system
• Heuristic Search Hypothesis: cognition is reflected in an intelligent search strategy that finds a solution without exhaustive brute-force search

Question 37

What is the binding problem?

Answer 37

The binding problem concerns the neuronal basis of sensory integration, i.e. the ability of the brain to construct uniform perceptions from a multitude of sensory impressions.

Question 38

What are the two key mechanisms in Enaction?

Answer 38

• Phylogeny: interactions are structurally determined by the system’s innate capabilities
• Ontogeny: the system is structurally coupled with the environment