Chapter 2 Notes – Cognition

1.       Perception – uses previous knowledge to gether and interpret the stimuli registered by the senses.

2.       Oject or
Pattern Recognition – you identify a complex arrangement of sensory
stimuli.

3.       Distal
Stimulus – is the actual object that is “out there” in the environment - for example, the
telephone sitting on your desk.

4.       Proximal
Stimulus – is the information registered on your sensory receptors – for
example, the image on your retina created by the telephone.

5.       Iconic
Memory – visual sensory memory, allow an image of a visual stimulus to
persist for about 200 to 400 milliseconds after the stimulus has disappeared.

6.       Primary
Visual Cortex – located in the occipital lobe of the brain; the portion of
the cerebral cortex that is concerned with the basic processing of visual
stimuli.

7.       Illusory
contours – we see edges even though they are not physically present in
stimulus.

8.       Template
Matching Theory

a.       You compare a stimulus with a set of templates,
or specific patterns that you have stored in memory. This theory is too simplified and only
applicable in very few cases.

9.       Feature Analysis Theory

a.       Propose that a visual stimulus is composed of a
small number of characteristics or components.

10.   Recognition by Components Theory

a.       A given view of an object can be represented as
an arrangement of simple 3D shapes called geons.

11.   Viewer centered approach

a.       Proposes that we store a small number of views
of 3-D objects, rather than just one view.

12.   Difference Between Bottom-Up Processing and
Top-Down Processing

a.       Bottom up processing

                                                               i.      Emphasizes the importance of the stimulus in
object recognition. The image is “built up” from its components.

b.      Top Down Processing

                                                               i.      Emphasizes how a person’s concepts and
higher-level mental processes influence object recognition. Using all of our brains to come in from the
top, from the big picture to the actual object.

Chapter 1 Notes – Cognition

1.       Cognition – or mental activity, describes the acquisition, storage, transformation and
use of knowledge.

2.       Cognitive Psychology

a.       Sometimes it is a synonym for the word cognition, and so it refers to the
variety of mental activities such as perception, memory, imagery, language,
problem solving, reasoning and decision making

b.      Sometimes it refers to a particular theoretical
approach to psychology. Specifically, the cognitive
approach is a theoretical orientation that emphasizes people’s knowledge
and their mental processes.

3.       History of Cognitive Psychology

a.       Wilhelm
Wundt – 1879

                                                               i.      Introspection, in this case, means that
carefully trained observers would systematically analyze their own sensations
and report them as objectively as possible.

b.      Herman
Ebbinghaus – 1885, 1913

                                                               i.      Devised his own methods for studying human
memory. Nonsense syllables (like DAK) to learn and test his performance.

c.       Mary
Calkins – 1894

                                                               i.      Reported the recency effect, which refers to the observation that our recall is
especially accurate for the final items in a series of stimuli.

d.      William
James –

                                                               i.      Wrote Principles of Psychology in 1890, which
predicted a lot of different mental processes.

e.      Behaviorism

                                                               i.      Psychology must focus only on objective,
observable reactions; emphasizes the environmental stimuli that determine
behavior.

                                                             ii.      Operational
definition – a precise definition that specifies exactly how a concept is
to be measured in an experiment.

f.        Gestalt
Psychology-

                                                               i.      Emphasizes that humans have basic tendencies to
organize what they see and that the whole is greater than the sum of its parts.
Overall quality that transcends the individual elements.

g.       Frederick Bartlett – early 1900s

                                                               i.      Conducted research on memory. Proposed that human memory is a constructive
process in which we interpret and transform the original material, often making
gthis material more consistent with our own personal experiences.

4.       Jean Piaget

a.       Did research with children to show that infants
develop object permanence, the
knowledge that an object exists, even when it is temporarily out of sight.

5.       Information-processing approach

a.       Mental process can best be understood by
comparing it with the operations of a computer, and

b.      A mental process can be interpreted as
information progressing through the system in a series of stages, one step at a
time.

6.       Atkinson-Shiffrin model

a.       Proposed that memory can be understood as a
sequence of discrete steps, in which information is tranferred from one storage
area to another.

b.      Sensory memory

                                                               i.      A large-capacity storage system that records
information from each of the senses with reasonable accuracy. Lost in 2 seconds or less.

c.       Short-term
memory – now called working memory

                                                               i.      Contains only the small amount of information
that we are actively using. Lost in 30 seconds or less, unless they are somehow
repeated.

d.      Long-term
memory –

                                                               i.      Long term memory has an enormous capacity
because it contains memories that are decades old, in addition to memories that
arrived several minutes ago. This memory is relatively permanent.

7.       Ecological Validity

a.       Studies have ecological validity if the conditions in which the research is
conducted are similar to the natural settings to which the results will be
applied.

8.       Cognitive Neuroscience

a.       Combines the research techniques of cognitive
psychology with various methods for assessing the structure and function of the
brain.

9.       Brain Lesions

a.       Refers to the destruction of tissue, most often
by strokes, tumors or accidents.

10.   Positron Emission Tomography – PET

a.       Researchers measure
blood flow by injecting the participant with a radioactive chemical just before
this person performs a task. Can be used
to study attention, memory and language.

11.   Functional Magnetic Resonance Imaging – fMRI

a.       Based on the principle that oxygen-rich blood is
an index of brain activity. This magnetic field produces changes in the oxygen
atoms. A scanning device takes a “photo” of these oxygen atoms while the
participant performs a cognitive task.

12.   Event-Related Potential technique- ERP

a.       Records the tiny fluctuations (lasting just a
fraction of a second) in the brain’s electrical activity, in response to a
stimulus.

13.   Single-cell recording technique

a.       Researchers study characteristics of an animal’s
brain and nervous system by inserting a thin electrode next to a single neuron,
then measure the electric activity generated by that cell.

14.   Artificial Intelligence (AI)

a.       A branch of computer science, seeks to explore
human cognitive processes by creating computer models that exhibit
“intelligent” behavior.

15.   Computer metaphor

a.       Our cognitive processes work like a computer,
that is, a complex, multipurpose machine that processes information quickly and
accurately.

16.   Parallel Distributed Processing (PDP)

a.       The PDP approach argues that cognitive processes
can be understood in terms of networks that link together neuron-like units; in
addition, many operations can proceed simultaneously – rather than one step at
a time.

b.      Also called connectionism or neural networks.

c.       Cerebral
cortex – the outer layer of the brain that is responsible for cognitive
processes.

d.      Parallel
processing – where many singals handled at the same time, rather than
serial processing.

e.      Five
principles of PDP processing

                                                               i.      Parallel processing - many cognitive
processes are based on parallel
operations, not serial operations

                                                             ii.      Nodes - The neural activity
underlying a particular cognitive procedure is typically distributed across a
relatively broad area of the cerebral cortex, rather than being limited to a
single, pinpoin-sized location. Each location of neural activity is called a node, and the nodes are interconnected
in a complex fashion with many other nodes.

                                                            iii.      Strengthening of connection – when
two nodes are activated at the same time, the connection between the nodes is
strengthened. Thus, learning is defined as a strengthening of connections.

                                                           iv.      Conpensation for incomplete information –
if information is incomplete of faulty, you can still carry out most cognitive
processes. Our pattern recognition, memory, and other cognitive processes are
extremely flexible.

f.        Serial
processing –

                                                               i.      In which only one item is handled at a given
time, and one step must be completed before the system can proceed to the next
step in the flowchart.

17.   Cognitive science

a.       A contemporary field that tries to answer
questions about the mind. Includes cognitive psychology, neuroscience, computer
science, philosophy, linguistics, anthropology, sociology, and economics.

Pattern Recognition,
Attention, and Consciousness

I.                   Pattern Recognition: Vision

a.       Definition
– identification of a complex arrangement of sensory stimuli

b.      Template-Matching
Model

                                                              i.      Templates: stored (specific) models of all recognizable patterns

                                                            ii.      Compare item of interest with templates of items stored
in memory

                                                          iii.      To identify an object, every aspect of the object must
match the template perfectly

                                                          iv.      Problem: there is enormous variability in patterns that we can recognize

1.      Requires
an infinite number of templates for any given object

2.      Object
identification would take a long time

c.       Prototype
Model

                                                              i.      Stores a prototype of an object or pattern

1.      Prototype:
abstract, idealized patterns

                                                            ii.      Compare a target object with our existing prototype and
identify an object based on closest match

1.      Tolerate
minor variations between the object and prototype

2.      Where
do the prototypes come from?

d.      Distinctive
Feature Model

                                                              i.      Feature: a very simple pattern: a fragment or component
that can appear in combination with other features

                                                            ii.      Recognize the whole pattern by breaking objects apart

                                                          iii.      Hubel and Wiesels’ research

1.      In
the cortex of a cat, physiological evidence for special receptors that respond
to only certain features

2.      Recognize
an object as a result of activation of a number of specific cells

                                                          iv.      To indentify an object, it is not just the features
that influence recognition, but also the features background

1.      Nontargets

2.      Duncan
& Humphreys showed that features of the nontargets influence pattern
recognition

3.      We
can shut-off some features to increase recognition speed

4.      It
is more difficult to locate a target when it shares features with nontargets

                                                            v.      Top-down processing

1.      Conceptually
driven processing: higher cognitive processes assist in pattern recogintion,
cognitive processes alter visual recognition

a.       So,
how might top-down processing influence pattern
recognition within the model?

                                                                                                                                      i.      The more likely the letter, the more activation and the
greater weight assigned to that letter

                                                                                                                                    ii.      Higher level knowledge and expectations assist your
processing of perceptual information

                                                                                                                                  iii.      Word superiority effect:

                                                                                                                                  iv.      Faster at identifying a single letter within the
context of word than when the letter is presented alone

1.      Each
letter sends an excitatory sign to other letters of a familiar word

                                                                                                                                    v.      How does the model explain face recognition?

1.      When
all the familiar features of a face are prsent, you are faster at identifying
even a single feautre because of excitatory signals sent to that feature from
other features.

                                                          vi.      Bottom-up processing

1.      Data
driven processing: using only features and clues in the target stimulus to
identify the object

e.       Computational
Approach

                                                              i.      We perform computations on incoming stimuli; the
products of the computation ultimately permit pattern recognition

                                                            ii.      Recognition by components (RBC) model

1.      Irving
Biederman

2.      Identify
3 dimensional objects by recognizing the component geons and arrangement of
geons (geometric icons)

f.       Connectionist
Model (neural networks, parallel distributing processing)

                                                              i.      Compute an object based on both bottom-up and top-down
processing

                                                            ii.      Three levels

1.      Input
level – cells receive input from the environment via feature detectors

2.      Hidden
units – the units receive either positive activation that leads to “excitation”
or negative activation that leads to “inhibition”

a.       “internal”
processing

3.      Output
units

a.       Connections
from all parts are computed simultaneously

b.      Response
in whatever form is made as a result of registering multiple computations

                                                          iii.      Word superiority effect

                                                          iv.      Face recognition

g.      Gestalt
Psychology

II.                Pattern Recognition: Audition

a.       For
vision, you receive information across the visual field or across space

b.      For
audition, you receive information about sounds in the environment across time

c.       Template
and prototype explanations for pattern recognition in audition have been
rejected

d.      Distictive
feature approaches do not account for top-down influences

e.       Conceptually
driven recognition – top-down processing

                                                              i.      Warren and Warren’s research

1.      It
was found the *eel was on the axle

2.      It
was found the *eel was on the shoe

3.      When
Ss were asked to repeat exactly what they heard, the reported the sentence
replacing the cough with the phoneme to complete the word

4.      Most
Ss reported no awareness of the cough at all.

f.       Selective
attention in auditory perception

                                                              i.      Selective attention – when one is confronted with
multiple tasks and must attend to one task while disregarding other tasks

1.      Cocktail
party effect

                                                            ii.      Filter theories – theories that suggest we select out
an important message and filter out unimportant messages

1.      dichotic
listening task – while wearing earphones, Ss are presented with two different
messages one to each ear

                                                          iii.      Cherry’s research – 1953

1.      Shadowing
requires Ss to repeat the message heard in one ear aloud as it is being said
while ignoring the other ear’s message

2.      Ss
could do this task fairly well, but tended to shadow the ear in a monotone.

3.      Altered
the message to the unattended ear after the Ss had been shadowing for a while
and found the following:

a.       Ss
could detect a difference in the background message when it changed from speech
to tone

b.      Noticed
when the voice in the unattended ear changed from male to female and vice versa

c.       Did
not notice when the voice in the unattended ear switched languages

d.      Could
not indentify any words or phrases

                                                                                                                                      i.      Even when a single word was repeated 35 times

e.       Suggest
we do monitor some aspects of the unattended channel, like pitch

g.      Selection
models

                                                              i.      Broadbent’s early selection model –

1.      Selection
occurs in the initial stage of information processing

2.      Selection
is based upon physical features like tone, loudness, location, pitch, etc.

3.      Problems:

a.       Treisman
(1960,1964)

                                                                                                                                      i.      In one study, she used the same speaker for both messages

1.      Cannot
filter the message based upon physical characteristics of the speaker

2.      Although
more difficult, Ss could still shadow the one message

                                                                                                                                    ii.      Treisman concluded that we select or filter out info
based upon the content of the message

                                                            ii.      Stage 2 selection model

1.      At
this stage, selection is based on grammatical and semantic features of the
stimulus

2.      Treisman’s
evidence

a.       After
Ss shadowed a few words of the message in one ear (with the same voice), the
message was switched to the unattended ear

                                                                                                                                      i.      Ss continued to shadow the same message, but now in the
ear they were told to ignore

                                                                                                                                    ii.      Ss were not aware the message had switched ears

b.      We
are not selecting out as early as Broabend suggested

c.       Treisman
believed all messages receive some low level analysis

d.      Selection
for a single channel occurs at the semantic level

                                                          iii.      Stage 3: late selection model

1.      Deutsch
and Deutsch’s research

2.      All
stimuli are completely analyzed and that selection occurs at the level of
responding

III.             Attention: Mechanisms, Processes, and Mental Resources

a.       Automatic
and conscious processing

                                                              i.      Automatic processing (divided attention by Treisman)

1.      Stroop
effectm – green written in blue

a.       Priming:
when there is automatic access to info in memory

b.      For
the Stroop Effect, letters provide automatic access to the meaning of the word

c.       Fits
with the connectionist/PDP models

2.      Not
part of concious awareness

a.       You
are aware of the products of processing

b.      Not
aware of how this information
was made available

3.      Consumes
little or no process

a.       Does
not interfere with other processes

                                                            ii.      Controlled processing (focused attention by Treisman)

1.      Occurs
only with intention

2.      Open
to awareness

3.      Requires
attentional resources

a.       Can’t
do more than one task

b.      Serial
processing of info

                                                          iii.      Practice and memory

1.      With
practice, a complex and attention demanding task becomes easy, less resource
demanding

2.      Practice
helps you store info in memory about how to perform the task more efficiently

a.       Shiffirin
& Schneider

3.      Synthesis
of perception and attention

a.       Limited
amount of attentional resources

b.      We
can focus our attention on a single demanding task or divide our attention
among 2 less demanding tasks

c.       Automatic/controlled
processing occurs on a continuum

b.      Synthesis
of attention and memory

c.       Illusory
conjunctions in attention

                                                              i.      Illusory conjuctions: inappropriate combination of
features

                                                            ii.      Treisman and Gelade’s research

1.      Spotlight
attention/focused attention

2.      Asked
Ss to search a visual display for either a simple feature or a conjunction

a.       Simple
features were found rapidly, regardless of the display size (number of
nontargets)

                                                                                                                                      i.      Spotlight permitted search of the entire display at the
same time

b.      When
engaging in a conjuction search, display size was a factor

                                                                                                                                      i.      Took more time as the number of nontargets increased

                                                                                                                                    ii.      The spotlight has to look at one letter at a time

                                                          iii.      Physio support

1.      Feature
inhibitory mechanism: when features of nontargets are very different from the
target, we simultaneously inhibit irrelevant distractors

d.      Biology
of attention

                                                              i.      Relevant pathways

                                                            ii.      Methodology

Introduction and
History of Cognitive Psychology

I.                   Cognition – a collection of mental processes and
activities used in perceiving, remembering, thinking and understanding, as well
as the act of using these processes.

a.       Memory
– mental processes involved in the acquisition and retention of information for
later removal

                                                              i.      3 mental activities – awareness of a stimulus when the
original stimulus is no longer present

1.      Acquisition

2.      Retention

3.      Retrieval

II.                History of Cognitive Psychology – evolved from the
disciplines of philosophy and physiology

a.       Wundt
– first psychology lab in Germany in 1879

                                                              i.      Introspection: a method in which one looks carefully
“inward” and reports on current inner sensations and experience

                                                            ii.      Psychology should study “conscious processes and
immediate experience”

                                                          iii.      Rules: “observers” are well trained, observations can
be replicated, and controls ensure systematic study of variables of interest

b.      Titchner

                                                              i.      Student of Wundt

                                                            ii.      Elements or components of the mind

                                                          iii.      Structuralism- the study of the structure of the
concious mind, including sensations, images, and feelings.

                                                          iv.      Unable to replicate using introspection

                                                            v.      Both this approach and introspection lost popularity

c.       Ebbinghaus

                                                              i.      The mind’s ability to form associations

                                                            ii.      A more objective technique/method for the study of
cognitive activity

                                                          iii.      List of nonsense syllables with CVC letter construction

1.      Prevent
previous knowledge from influencing memory

2.      Prime
word and target word

3.      Studied
savings and forgetting

                                                          iv.      Associations

d.      James

                                                              i.      Functionalism- study of funciton of conciousness
“asking WHY?”

1.      Memory
consists of 2 components

a.       One
part processes information that is immediately available or currently in your
awareness

b.      The
other part of memory serves as a repository of past experiences

e.       Watson

                                                              i.      Dominated american psychology from about 1910 until the
1950s

                                                            ii.      Study only behavior because it is both observable and
quantifiable

                                                          iii.      No reference to internal mental processes

                                                          iv.      More “scientific”

1.      Little
advancement was made in cognitive psychology

                                                            v.      Towards the end of the era, some pseudo behaviorists
began to study more than S-R relationships

1.      Became
interested in how the organism intervened between the stimulus and response

2.      S-O-R

                                                          vi.      Behaviorism

                                                        vii.      Cognition was discouraged

f.       Dissatisfaction
with behaviorism

                                                              i.      Behaviorism could not explain a lot of questions about
human activity

g.      “Cognitive
revolution” began in 1950s

                                                              i.      Behaviorism was rejected

                                                            ii.      Chomsky

1.      Language
is too novel

2.      Not
simply a product of S-R, but rather language follows rules stored in memory

III.             Current Directions

a.       Information
processing approach – cognitive activity occurs via a series of stages

                                                              i.      Similarities between humans and computers

1.      Humans
are active processors of information

a.       Input à do something with it à output

2.      Both
are limited in terms of how much info they can process at one time

3.      Both
can store a large amount of info

4.      Computers
can perform some tasks like human

                                                            ii.      Differences and Limitations to this approach

a.       In
some instances, computers do not accurately simulate human performance

                                                                                                                                      i.      Computers can outperform humans in some areas

2.      Hardware
is different

                                                          iii.      Serial processing

1.      Computers
process information serially; humans process information in a parallel fashion

                                                          iv.      Parallel processing

1.      Parallel
processing is many items are processed simultaneously

2.       

b.      Parallel
distributed processing (PDP) approach (AKA: neural networks/connectionist
model)

                                                              i.      McClelland, Rumelhart, and colleagues

                                                            ii.      A series of networks that are linked together by
neuron-like units

                                                          iii.      Brain activity occurs at nodes or different locations
across the brain

1.      Nodes
interconnected via neurons

2.      Once
threshold is met, activity in one node influences activity in other nodes

a.       Producing
either excitation or inhibition in connected nodes

IV.             Breadth

a.       Cognitive
neuroscience

                                                              i.      How cognitive theories explain/compliment the structure
and function of the brain

                                                            ii.      Ss engage in some cognitive in some cognitive task and
measure, via PET or fMRI, brain activity

b.      Cognitive
science

                                                              i.      Interdisciplinary field that studies the internal
representations of the external world

                                                            ii.      Includes computer science, philosophy, psychology,
neuroscience, anthropology, etc.