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History and Introduction to Cognitive Psychology
Chapter 1
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What is Cognitive Psychology?
Cognition co- + gnoscere to come to know. Knowing requires mental activity which involves acquiring,
storage, transformation and use of knowledge (Matlin, 2002).
Cognitive Psychology deals with how people perceive, learn, remember and think about
information (Sternberg, 2003) and how do they use this information (Matlin, 2002).
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Why study Cognitive Psychology?
1. Cognitive psychology holds a major domain in human psychology.
2. It studies the mind and how it works.
3. And it has a widespread influence on other areas of psychology.
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History of Cognitive Psychology
Generally speaking two approaches have been used to study the mind.
1. Historically, philosophical approaches have rendered an understanding to the workings of the mind using introspection.
2. And biology, has used observational (and empirical) methods to study the mind.
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Mind & Reality
Reality does not reside in concrete objects but
in abstract forms represented in our
mind.
Reality lies only in the concrete world of objects accessed
through the senses.
Plato (ca. 447-327 BC) Aristotle (384-322 BC)
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Comparison
Rationalism Empiricism
Understanding of mind (or knowledge) through logical analysis and introspection
(rationalism).
Observations of the external world are the only
means to arrive at truth (empiricism).
Innateness of mind or mental faculties.
Acquired experiences through interaction with
the environment.
Theory building in psychology today.
Experimentation in psychology today.
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Seventeenth Century
Descartes agreed with Plato and emphasized
reflective methods (rationalism) over
observation to study mind.
Locke favored Aristotle and emphasized observation as a
method (empiricism) to study mental processes.
Rene Descartes (1596-1650) John Locke (1632-1704)
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Immanuel Kant
In eighteenth century German philosopher
Kant addressed the issue of rationalism and
empiricism and said that both approaches must be
used to decipher truth and about reality of
mind. (1724-1804)
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Structuralism
Wilhelm Wundt (1832-1920)
1. First psychology lab in Leipzig, Germany (1879).
2. To analyze the structure of the mind. Through the method of introspection.
3. Elements of mind: sensation, feelings, and images.
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Functionalism
1. Mind or consciousness cannot be divided into elements.
2. Introspection cannot yield measures about the mind.
3. Mind or consciousness have adaptive value.
William James (1842-1910)Self-portrait
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Behaviorism
1. No room for mind or consciousness.
2. Overt behavior needs to be the scientific domain of psychology.
3. Behaviorism is an extreme form of associationism between environment (S) and observable behavior (R). John Watson (1878-1958)
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Gestalt Psychology
1. Opposed behaviorism and structuralism.
2. S-R components or mental elements could not explain behavior or mind of an individual.
3. Holistic approach to understanding behavior or mind.
Wolfgang Kohler (1887-1967)
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Associationism
1. Studied “higher mental processes”, like memory and forgetting.
2. Used systematic experimental introspection.
3. Followed Aristotelian law of association. Repetition improves memory.
Hermann Ebbinghaus (1850-1909)
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Memory Studies
Ebbinghaus Bartlett
In the late 19th and early 20th century we see differences in approaches to the problem of memory. Ebbinghaus
promoted quantitative study of memory using nonsense material, Bartlett on the other hand used qualitative
methods to study memory.
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Is the debate over?
Certainly not! Understanding mind and its reality has its adherents belong both to nurture (acquired
mind) or nature (innate mind) or both domains.
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Early Beginnings of Cognitive Psychology
Stimulus Response
Brain
Cell Assembly
1. Lashley’s research showed that large amounts of the brain could be destroyed without affecting learning.
2. Hebb, Lashley’s student proposed stimulation (learning) led to forming strong connections among neurons called cell assemblies.
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Birth date of Cognitive Psychology
Ulric Neisser George Miller
Herbert Simon
1. Cognitive psychology was born on Sep. 11, 1956, when Neisser, Miller, and Simon read seminal papers at a symposium at MIT.
2. Neisser wrote the first book of Cognitive Psychology (1967).
3. Defined how people learn, structure, store and use knowledge.
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Computer Sciences
1. In 40s and 50s, electronic engineering and computer sciences started developing machines and programs that mimicked human learning and thinking.
2. Turing developed a test (Turing test) for a computer to think like a human.
Alan Turing (1912-54 )
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1960s
A number of sciences and disciplines like psychobiology, linguistics, anthropology, computer sciences and artificial intelligence started gathering
data that developed the strong foundations of cognitive psychology.
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Current Trends in Cognitive Psychology
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Cognitive Science
Cognitive science is a broad category of loosely associated disciplines that include psychology,
philosophy, computer science, linguistics, anthropology, neuroscience and of course cognitive
psychology is also a part of its domain.
Most researchers are likely to work in an interdisciplinary fashion.
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Cognitive Neuroscience
Can we explain cognitive processes by studying the anatomy (structure) and physiology (function) of the
brain?
The field of cognitive neuroscience expanded around the 1980s when neuroscientists started using imaging techniques on people performing
different cognitive functions.
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Neuroscientific Methodology
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History of Brain Lesions
Human brain damage (gladiators) and its consequences were noted by Hippocrates who
wrote that people’s behavior changed after such damage.
Similar observations had been made in wars victims in the 19th century. It was not until world war II that physicians started to document disorders that were caused by damage to certain regions of the brain.
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Brain Lesions
Our understanding of brain function comes largely from brain lesion studies in animals. Lesion studies
provide clues to the organization of the brain. Which brain region engages in what kind of cognitive
function.
Cognitive functions can remain elusive because of recovery of function (Lashley, 1932).
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Brain Angiography
Is an X-ray method to look at arteries of the
brain. Provides information about
abnormalities in the brain like strokes or
tumors.
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Carotid artery in the brain
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CT Scan
Is also another X-ray method that images the brain and makes use of multiple X-ray photos
taken with a moving X-ray device. Finally
reconstructing a 3D picture of the brain.
Resolution poor. Cannot determine structure
function relationships.
imagin
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CT scan of the brain
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Magnetic Resonance Imaging (MRI)
A strong magnetic pulse and moves molecules in
the brain. Motion of these molecules are picked up as radio frequencies and
reconstructed in 3-D images. MRI has better
resolution than CT scans. No structure function
relationship.
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MRI scan of the brain
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Positron Emission Tomography (PET)
Increased radio-labeled glucose activity is
scanned in the brain while subjects engage in
different cognitive processes. Spatial Resolution good.
Temporal resolution not good. Invasive procedure.
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PET scan of the brain
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Functional Magnetic Resonance Imaging (fMRI)
Detects changes in blood flow to particular areas of
the brain when these areas are active. It provides both
an anatomical and a functional view of the
brain. Not invasive like PET scans and provides a
better spatial and temporal resolution.
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fMRI scan of the brain
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Event-related Potential
Event-related potential measures the brain's
electrical activity (potentials) as it
corresponds to impinging stimuli (events). Excellent
temporal resolution (faster response)
compared to PET or fMRI.
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Event-related Potential
Single-Cell recordings in non-human subjects provide a wealth of information on the functioning of a single
or multiple neurons. For example, Hubel & Wiesel (1960) showed responses of a single neuron in the primary visual cortex detecting an edge (feature).
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Computer Sciences
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Computers and Mind
Parallels between human mind and machines have been made since ancient
times. Computer analogy is recent. There are number
of attributes that are similar between computers
and humans.
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The first electricaldigital computer
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Artificial Intelligence (AI)
1. Machines or programs using intelligence to solve complex problems, the way humans solve problems.
2. Application will include computers doing medical diagnoses, flying jet planes, being the senses of the disabled.
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Artificial Intelligence (AI)
3. AI involves making programs or devices that are efficient, flexible, and learn through experience. They may or may not mimic human consciousness.
4. Computer simulation involves designing a system that simulates human performance on a selected cognitive task.
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R2-D2 (Artoo-Detoo)& C-3PO (See-ThreePio)
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Cognitive Sciences
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Processing
Serial Processing involves processing of information or data in a stage by stage format. Time consuming.
Parallel Processing on the other hand involves processing information or data simultaneously. Much faster.
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Parallel Distributed Processing (PDP)
McClelland and Rumelhart (1986) proposed that cognitive processes must be understood in terms of
networks that process information in parallel.
Characteristics of PDP Model
1. Many cognitive processes are based on parallel operations.
2. Neural activity for a cognitive process is spread out in the brain and is termed as a node.
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Parallel Distributed Processing (PDP)
Characteristics of PDP Model
3. A node reaches a critical activation level to affect another node
4. When two nodes are activated the bond between them strengthens.
5. Multiple nodes and parallel processing aids and reconstructs information that is partial or inadequate to begin with.
Node
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Issues in CognitivePsychology
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1. Nature or Nurture?
If we believe in nature affects our cognitive functions then we should design our experiments
looking at environmental factors as the cause cognitive phenomena. On the other hand if we
believe in nurture then our experiments need to look at innate/inborn processes.
Today cognitive psychologists believe that both the nature and nurture interact to affect cognitive
phenomena.
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2. Rationalism or Empiricism?
What kind of methodology should we use to study cognitive phenomena? Should we use logical reasoning to explore cognitive phenomena or
should we engage in observation and experimentation to do the above?
3. Structures or Processes?
Should we study the structure (contents, attributes, and products) of the mind or should we study the
processes of our mind (thinking)?
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4. General or Specific Domains?
Do cognitive processes limited to singular domainsor do they apply to multiple domains in our minds? Do processes/functions in a single domain similar
to other domains?
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5. Causal or Ecological Validity?
Should we study cognitive processes using controlled [but artificial] experiments to make valid
causal inferences – or develop experiments [resembling life] that provide us with ecologically
valid findings but at the cost of losing some experimental control?
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6. Applied or Basic Research?
Should we study cognitive processes for the sake of simply understanding them or should we study
them to help people make use of them for practical considerations?
7. Biological or Behavioral Research?
Should we study cognitive processes by analyzing the brain and its functions – or should we study
these processes by behavioral measures, reaction times, errors etc?