cognitive psychology lecture 1: introduction james matthews and john toner

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Cognitive Psychology Lecture 1: Introduction James Matthews and John Toner

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Cognitive Psychology

Lecture 1: IntroductionJames Matthews and John Toner

Course Layout

Topics to be covered:• Memory• Attention• Mental Imagery• Language• Problem Solving & Expertise• Reasoning, Decision Making & Judgements• Consciousness• Knowledge

Course Completion

• Christmas ExamFormat to follow.

• Class presentationEach student will have to give one 10 minute presentation over the course of the 12 weeks based on a set article.

Course Completion

Class presentation– Short: 10 mins, 10 - 15 slides

– Everyone expected to read the article over the course of the week

– Presentation should simply summarise the main methods (where relevant) and arguments of the article

– Presentation should finish with a ‘points for discussion’ slide bringing in their own thoughts and facilitating debate

Reading (Library: GEN/SLC 153.4)

Core text:Eysenck, M., & Keane, M. (2005). Cognitive Psychology: A student’s handbook (5th ed.) Hove, East Sussex: Psychology Press

Other sources:Reisberg, D. (2006) Cognition: Exploring the Science of the Mind (3rd ed.) New York: W.W. Norton & Company

Sternberg, R. (2003). Cognitive Psychology (3rd ed.) Fort Worth, Texas: Harcourt Brace

Article Search

http://www.ucd.ie/library/

Electronic Resources

List of Library Databases

PsychInfo

Cognition

The word cognition is derived from the Latin word cognoscere, meaning “to know” or “to come to know”.

Cognition is therefore the activities and processes concerned with the acquisition, storage, retrieval and processing of knowledge.

What is Cognitive Psychology?

It is the scientific study of how the mind works

“...cognitive psychology deals with how people perceive, learn, remember, and think about information.”— Sternberg (1999)

“Cognitive psychology [is] the study of processes underlying mental events”

— Solso (2005)

What do cognitive psychologists study?

Memory Decision Making

Attention Perception

Learning Neurobiology

Cognitive Development Concept Formation

Emotion Artificial Intelligence

Language Problem Solving

Mental Imagery Animal Cognition

Things which cognitive psychologists may seek to explain. . .

Why do we find it difficult to describe how to tie a shoelace without moving our hands or looking at our shoes?

Things which cognitive psychologists may seek to explain. . .

What processes are involved in planning a novel route through familiar terrain.

(e.g. How do I get from UCD to town via Dundrum)

Things which cognitive psychologists may seek to explain. . .

How can we recognise a song from its first few beats?

Things which cognitive psychologists may seek to explain. . .

Phenomena like that shown in this video

http://gigglesugar.com/349186

Approaches to Cognitive Psychology

• Experimental Cognitive Psychology

• Computational Cognitive Science

• Cognitive Neuropsychology

• Cognitive Neuroscience

Experimental Cognitive Psychology

Tightly controlled experiments carried out under laboratory conditions on healthy individuals.

Experiments often designed to disrupt cognitive processes and thus reveal their workings.

(e.g. Distracting participants attention)

Findings lead to theories, which in turn lead to testable claims

(e.g. “Instrumental music does not disrupt reading”)

Experimental Cognitive Psychology

Sample Experiment: Effect of arousal level on reaction time.

Reaction time assessed on a machine where buttons light up and time to respond is measured

Arousal assessed through heart rate measurement

Conditions: 1) After rest2) After cognitive load3) After exercise4) After caffeine5) After exercise and caffeine

Experimental Cognitive Psychology

Some limitations:• Is behaviour in a laboratory fundamentally different

to that in real world settings. Are the findings of experiments ecologically valid?

• Does not look directly at brain function, but rather the explicit behavioural results of brain function. Thus we may miss something.

• Tendency to negate individual differences by averaging many participants’ performances. Does not allow for the possibility of unique cog. function

Computational Cognitive Science

Computational modelling involves recreating some aspect of human cognition in the form of computer program, flow chart or formula in order to predict behaviour in novel situations

Computational Cognitive Science

Computational models can vary in complexity from relatively simple flow charts to highly detailed connectionist networks.

In these latter models units or nodes are connected to many others.

In a particular scenario units take the weighted sum of the inputs coming to it and produce a single output to another unit.

Networks can be arranged in complex layered systems

Computational Cognitive Science

Some limitations• There are usually many ways to model a particular

cognitive phenomenon• There is a lack of a definite method for relating a

computational model’s behaviour to human behaviour

• It is extremely difficult, if not impossible, to take every cognitive factor into account when creating a model (e.g. Do models of language processing take into account the emotional connotations of particular sentences for particular individuals?)

Cognitive Neuropsychology

Concerned with the cognitive functioning of those who have suffered brain damage

• Damage to region X disrupts ability Y• People who have lost ability Y also have problems

with ability Z

From studying people with brain injuries we make assertions about healthy brain function

Cognitive Neuropsychology

Sample Case: Frontal Lobe damage• People with frontal lobe damage often show little

cognitive deficit when given IQ tests• However they have extreme difficulty with things

like–Socially acceptable behaviours–Cognitive flexibility–Abstract thinking

• Frontal lobes are the area which differ to the greatest extent between human and ape brains

Cognitive Neuropsychology

Some limitations:• Ethically we cannot cause brain damage in

humans so we have to work with what we find. This damage is rarely ‘clean’

• Interpretation of findings in relation to those suffering damage to several areas is very difficult

• If ability Y is disrupted by damage to region X, it does not tell us what role X has in Y. Is it the functional centre, or simply a vital stage? There are 50 billion interconnected neurons.

• What was cog. functioning before injury?

Cognitive Neuroscience

Using brain imaging and brain anatomy to study ‘live’ cognitive functioning in healthy individuals

As the technology improves, these studies are becoming more influential and potentially useful

Methods include: (Details to follow!)• Single Unit Recording• Event Related Potentials (ERPs)• Positron Emission Tomography (PET)• (Functional) Magnetic Resonance Imaging (fMRI, MRI)• Magneto-encephalography (MEG)• Transcranial magnetic stimulation (TMS)

Cognitive Neuroscience

Cognitive Neuroscience

Some Limitations• Techniques are of questionable use with high-order

functioning which might not be organised in a concise way

• If data from several individuals is averaged the interpretations become accordingly blunt

• Tendency for research to be conducted for the sake of research. Papers can often be lacking any theoretical basis, and result in ad hoc hypotheses

• Threshold levels need to be set to disregard noise. These levels are a contentious issue!

Cognitive Neuroscience

Event Related Potentials (ERPs)• Electrical brain activity (EEG) is measured on the scalp• Several readings for the same stimuli are averaged to

counteract spontaneous background activity

Cognitive Neuroscience

Event Related Potentials (ERPs)

Pros:

Best detail of the timeline of cognitive events

Cons:Only useful with simple, low-level stimuliSkull and scalp distort emerging electrical waves

Cognitive Neuroscience

Positron Emission Tomography (PET)• Radioactive substance injected into the body and observed

as it gathers in blood vessels of brain• Activity levels are determined as (very mild) radioactivity

levels are measured by subtracting activity levels at rest from activity levels during a particular task

Cognitive Neuroscience

Positron Emission Tomography (PET)

Pros:

Maps wide range of cognitive activities including complex tasks

Reasonable location of active areas (3-4 millimeters)

Cons:Scans indicate total amount of activity over 60 seconds. Not sensitive to rapid changes in activity

How closely are changes in distribution of radioactive water related to neural activity?

Cognitive Neuroscience

Functional Magnetic Resonance Imaging (fMRI)• Radio waves produce neural activity picked up by a large

magnet. • If used to scan anatomy of brain for tumors etc. it is MRI. If

used during tasks to detect brain function it is fMRI.

Cognitive Neuroscience

Functional Magnetic Resonance Imaging (fMRI)

Pros:

No biological risks

Provides anatomical and functional information

Cons:Poor temporal resolution of a few seconds

How closely are changes in oxygenated haemoglobin related to neural activity?

Basic Brain Terms

Cortex: The outer layer of brain tissue

Basic Brain Terms

Lobes

Basic Brain Terms

Directions

Some experimental techniques

Eyetracking• Infrared cameras can detect where the eye is

looking and for how long• Used to study reading

Some experimental techniques

Eyetracking

Analysis of advertising, phobias, expert search patterns etc

Stimulus Presentation Software

Experiments may require a computerised stimulus presentation of stimuli in order to create ideal conditions and accurately measure responses

QuickTime™ and aH.263 decompressor

are needed to see this picture.

Reading

Eysenck & Keane: Chapter 1

Contact: [email protected]