Inleiding tot de
cognitiewetenschap
Hoorcollege 1: Emprisiche cyclus en methoden van
cognitieonderzoek
Drie manieren om de menselijke geest te bekijken:
1. Uit het brein
2. Cognitie
3. Kunstmatige intelligentie
Wat is een goede wetenschappelijke studie?
- Empirische cyclus gevolgd
- Repliceerbaar: helder en compleet gecommuniceerd
Empirische cyclus:
- Observatie inductie (theorievorming) deductie (hypothesevorming) toetsen
evalueren
- Probleemanalyse onderzoeksplan uitvoering resultaten conclusies
rapporteren
o Probleemanalyse: observatie, gat in de kennis, redenen voor replicatie
o Onderzoeksplan: onderzoeksvraag, hypothese, voorspellingen,
o Uitvoering: methoden
Beschrijvend onderzoek (observaties)
Correlationeel onderzoek (samenhang tussen twee soorten data)
Experimenteel onderzoek
o Resultaten:
o Conclusies:
o Rapporteren:
Methoden van cognitieonderzoek:
- Systeem meten:
- Modellen maken
- Experimenten
- Meetmaten
Hoorcollege 2: Exploring mental/inner space
Wat is cognitie?
- The mind is a set of cognitive faculties including consciousness, perception, thinking,
judgement and memory.
Cognitiewetenschap: interdisciplinaire wetenschappelijke studie van mentale processen.
,Bindende factor: informatieverwerkingsstroom: input verwerking output
De mens (en computers) zijn informatieverwerkers.
- Informatie representatie (informatiebeeld)
- Verwerker computatie (bewerken van representatie)
Representatie: something that stands for something else. Kenmerken van represetnaties:
- Representatie moet ergens gerepresenteerd worden
- Representatie moet refereren naar iets (een referent)
o Symbolische mentale representatie: symbool dat refereert naar iets anders
o Semantische representatie: het symbool heeft een betekenis
Intentionele relatie: representatie richt gedachte/gedrag naar referent
o Arbitrair: geen gedeelde fysieke kenmerken (Nederlandse vlag refereert naar NL)
Niet-arbitrair: gedeelde fysieke kenmerken
- Consistente relatie tussen representatie & referent
o Contingente causale relaties: Representaties zijn verbonden aan elkaar
- Representaties moeten geïnterpreteerd kunnen worden
Representaties en intelligentie:
- Formele logische systemen: symbolen combineren
- Physical symbol system hypothesis: als je formele logica en representaties hebt dan heb je
voldoende om intelligentie te creëren.
o Formele logica leidt tot intelligentie
o Symbol grounding problem
Types representaties:
- Concepten
o Verwijzen naar categorie
o Hiërarchisch geordend
o Abstract
- Proposities
, o Relaties tussen concepten
o Uitspraken, statements
o Waar of onwaar
- Regels
o Combineren of relateren van proposities
o Syllogismen
o Productieregels
- Analogie
o Toepassen eerder opgedane propositionele kennis in nieuwe situaties
o Redeneren
Procedurele kennis: kennis over handelingen.
Declaratieve kennis: feiten
Computatie: mentale mechanismen of operaties die representaties transformeren.
- Oneindig veel…
- Functionele categorieën: geheugen, perceptie, redeneren…
- Gemeenschappelijke ‘fundamentele’ processen
Drie niveaus om informatieverwerkingsprocessen te beschrijven:
- Computationeel niveau: WAT?
o Precieze omschrijving probleem voor informatieverwerker
o Precieze doelstelling van informatieverwerkingsproces
- Algoritmisch niveau: HOE?
o Hoe wordt de informatie exact gemanipuleerd?
o Wat zijn de verwerkingsstappen tussen input & output?
- Implementatieniveau: WAARMEE?
o Welk medium voert de informatieverwerking uit?
Symbolisme vs connectionisme
Serieel manipuleren van symbolische Parallelle activiatie van knopen in een netwerk
representaties
Syntax en symbolen
Lokale representaties Gedistribueerde representaties
Literatuur: Hoofdstuk 1 Introduction: Exploring mental space
Cognitive science can be roughly summed up as the scientific interdisciplinary study of the mind. Its
primary methodology is the scientific method. The term cognitive science refers not so much to the
sum of all these disciplines but to their intersection or converging work on specific problems.
To understand what cognitive science is all about, we need to know what its theoretical
perspective on the mind is. This perspective began with the idea of computation, which may
alternatively be called information processing. Information processors must both represent
information and transform information.
A representation is something that stands for something else. Four concepts:
1) A concept stands for a single entity or group of entities
2) Propositions are statements about the world and can be illustrated with sentences
, 3) Rules are yet another form of representation that can specify the relationship between
propositions
4) An analogy helps us make comparisons between two similar situations.
Four crucial aspects of any representation:
1) A representation beares must realize a representation.
2) A representation must have content. The thing or things in the external world that a
representation stands for are called referents.
3) A representation must be grounded. Thuse must be some way in which the representation
and its referent come to be related.
4) A representation must be interpretable by some interpreter.
The fact that a representation stands for something else means it is symbolic. Human mental
representations are said to be semantic, which is to say that they have meaning.
Intentionality means “directed on an object”.
The relation between inputs and outputs is known as an appropriate causal relation: if your friend
Sally told you about a cruise she took, an image of a cruise ship would probably pop into mind. This
might cause you to ask her if the food was good. Sally’s mention of the cruise was the stimulus input
that activated the internal representation of the ship in your mind. Once it was activated it caused
the behavior about the food.
Symbols can be assembled in formal logical systems. In a formal logical system symbols are combined
into expressions. These expressions can be manipulated using processes. The result of a process can
be a new expression.
According to the physical symbol system hypotheses (PSSH), a formal logical system can
allow for intelligence. The symbol grounding problem: to be meaningful symbols have to be
connected to the environment in some way. This imbues them with semantic quality. Computing
machines that are not embodied with sensors and effectors cannot acquire meaning. A
counterargument to this is that computer systems do have the capability to designate.
A concept is the most basic form of mental representation. A concept is an idea that represents
things we have grouped together.
A proposition is a statement or assertion typically posed in the form of a simple sentence. An
essential feature is that it can be proved true or false. A syllogism consists of a series of propositions.
The first two or more are premises, and the last is a conclusion. Propositions are more sophisticated
representation because they express relationships between concepts. Formal logic is at the core of a
type of computing system that produces effects in the real world: production systems. Inside a
production system, a production rule is a conditional statement: if x, then y.
Declarative knowledge is used to represent facts. Procedural knowledge refers to skills. Rules are just
one way of representing procedural knowledge.
The last form is analogy, although the analogy can also be classified as a form of reasoning. Thinking
analogically involves applying one’s familiarity with an old situation to a new situation.
The mind performs computations on representations. Any information process can be described at
several different levels. According to the tri-level hypothesis, biological or artificial information
processing events can be evaluated on at least three different levels.
, 1) Computation level: at this level, one is concerned with two tasks. The first is a clear
specification of what the problem is. The second task encounters at the computational evel
concerns the purpose or reason for the process. The second task consists of asking.
2) Algorithmic level: we can next inquire about the way in which an information process is
carried out. To do this, we need an algorithm, a formal procedure or system that acts on
informational representations. At this level is asking: What information-processing steps are
being used to solve the problem?
3) Implementation level: Here we ask: What is the information processor made op?
The levels clearly interact with one another, and each level can be further subdivided into its own
sublevels.
So far we have mostly been talking about computation as being based on the formal systems notion.
In this view, a computer is a formal symbol manipulator. In general we use the word syntax to refer
to the set of rules that govern any symbol. Manipulation here implies that computation is an active
process that takes place over time. They occur physically on some type of computing medium or
substrate.
The connectionist or network approach to computation differs from the classical formaly systems
approach. In the classical view, knowledge is represented in the form of symbols. In the connectionist
view, knowledge is represented as a pattern of neural activation, or a pattern of synaptic strengths,
that is distributed throughout a network and so is more global than a single symbol. The classical
view has processing occurring in discrete sequential stages, whereas in connectionism, processing
occurs in parallel through the simultaneous activation of many nodes or elements in the network.
A third view of representation comes from the dynamical perspective in cognitive science.
According to this view,, the mind is constantly changing as it adapts to new information.
The interdisciplinary perspective:
- The philosophical approach: The primary method of philosophical inquiry is reasoning, both
deductive and inductive. Deductive reasoning involves the application of the rules of logic to
statements about the world. Inductive reasoning: they make observations about specific
instances in the world, notice commonalities among them, and draw general conclusions.
- The psychological approach: psychologists attempt to understand not just internal mental
phenomena, but also the external behaviors that these internal phenomena can give rise to.
Psychoanalyitic psychology conceives of mind as a collection of differing and competing
mind-like subsystems, while behaviorism sees it as something that mas stimuli onto
responses.
- The cognitive approach: this placed renewed emphasis on the study of internal mental
operations. They believed that the mind could be understood in terms of information
processing.
- The neuroscience approach: the study of the brain and endocrine systems and how these
account for mental states and behavior is called neuroscience. The attempt to explain
cognitive processes in terms of underlying brain mechanisms is known as cognitive
neuroscience.
- The network approach: in this perspective, mind is seen as a collection of computing units.
These units are connected to one another and influence one another via their connections.
- The evolutionary approach: the field of evolutionary psychology applies the theory of natural
selection to account for human mental processes.
- The linguistic approach: they focus exclusively on the domain of language.
, - The emotion approach
- The social approach: examines the cognitive relations between individuals.
- The artificial intelligence approach: researchers in AI are concerned with getting computers
to perform tasks that have heretofore required human intelligence. AI also fives us insights
into the function of human mental operations.
- The robotics approach: Whereas AI workers build devices that “think”, robotics researchers
build machines that must also “act”.
- The embodied ecological approach: the body itself plays an important role in cognition.
Hoorcollege 3:
Wat is bewustzijn?
- Over (eigen) gedachtes of acties kunnen rapporteren toegang bewustzijn (acces
consciousness)
- Ervaren: fenomenologisch bewustzijn (phenomenological consciousness)
o Dit is subjectief, iemand anders kan er geen uitspraken over doen
Zienswijzen:
- Dualisme: geest en stoffelijke dingen
- Materialisme (fysicalisme): geen geest, maar stoffelijke dingen
- Idealisme (mentalisme): wel geest, geen stoffelijke dingen
Dualisme (descartes): substance (cartesiaans/klassiek) dualisme
- bestaat de geest? “Ik kan twijfelen aan het bestaan van alles wat ik waarneem. Als ik aan iets
twijfel, kan ik niet bewijzen dat het bestaat. Ik kan echter niet twijfelen aan het feit dat ik
twijfel. Twijfelen is een vorm van denken. Dat wat denkt kan niet tegelijkertijd niet bestaan.
Ik denk dus ik ben (cogito ergo sum). Denken is een eigenschap van de geest, dus de geest
bestaat.”
- Bestaat het lichaam? “God misleidt mij niet: mijn lichaam bestaat ook”.
- Thought constitutes the nature of the thinking substance. (geest)
- Extension in length, breadth and depth, constitutes the nature of corporeal substance
(lichaam)
Metafysisch realisme: er bestaat externe realiteit, los van ons bewustzijn.
Problemen bij dualisme:
- van welk spul is de geest gemaakt?
- Hoe kan verschillend spul interacteren?
o Descartes dacht dat er een tweeweg was.
Property dualisme: De geest heeft niet-fysieke eigenschappen
- Epifenomalisme (Huxley): de hersenen produceren bewustzijn.
Parallelisme: geen interactie tussen hersenen en geest.
Materialisme: er bestaan alleen stoffelijke dingen.
- Alleen materie en mechanistische verklaringen
