Exam 1 Cognitive Psyc 224-UIUC

Cognition

the acquisition, storage, transformation, and use of knowledge. Focus on the inner workings of the mind.

Cognitive psychology

-The branch of psychology that studies how we perceive, attend, recognize, remember...

-Problems: perception, learning, memory, language, consciousness

-Try to specify how info is internally represented

-All our mental activity is about something, and research aims to identify those processes and how information is represented.

Cognitive approach

a theoretical orientation that emphasizes people's thought processes and their knowledge.

For example, a cognitive explanation of ethnic stereotypes would emphasize topics such as the influence of these stereotypes on the judgments we make about people from different ethnic groups

Empirical evidence

scientific evidence obtained by careful observation and experimentation

Willhelm Wundt (1832-1920)

first person referred to as a psychologist. He was a german physiologist, and is regarded as a founder of psychological research. His laboratory established psychology as an individual science.

Invented method of introspection: analyzing own sensations and reporting them as objectively as possible

Problem with introspection: it is subjective, you may introspect that your eyes are moving smoothly across the text but research shows that eyes make small jumps

introspection

meant that carefully trained observers would systematically analyze their own sensations and report them as objectively as possible, under standardized conditions

For example, observers might be asked to objectively report their reactions to a specific musical chord, and to do so without relying on their previous knowledge about music.

Hermann Ebbinghaus

conducted the first rigorous studies of memories on himself. Very pivot figure in cognitive psychology

Interested in forgetting and how much we can retain.

Measured how long it took him to re-learn a previously learned listed of nonsense syllables (ex, BIC, PLUS)

He demonstrated that retention drops quickly and dramatically after a few days, and gradually tapers off.

Mary Whiton Calkins (1863-1930).

American psychologist who reported a memory phenomenon called the recency effect. In addition, they emphasized that psychologists should study how real people use their cognitive processes in the real world, as opposed to in artificial laboratory tasks

William James ((1842-1910)

psychologist and philosopher, and influenced development of psychology in the United States. Father of american psychology

Taught first psychology course

Believed in associationism and developed an early and influential model of memory built on the principle of associationism. There are multiple connections between memories that are connected by commonalities

Behaviorism

must focus on objective, observable reactions to stimuli in the environment, rather than internal processes

interested in quantifying the manner in which changes in an organism's environment produced changes in its behavior.

John B. Watson (1878 to 1958)

considered the father of behaviorism. We have learned responses to environmental stimuli.

emphasized observable behavior, and they typically studied nonhuman animals

operational definition

a precise definition that specifies exactly how a concept is to be measured

Gestalt Approach

emphasizes that we humans have basic tendencies to actively organize what we see, and furthermore, that the whole is greater than the sum of its parts

Frederic Bartlett (1886-1969)

discovered that people made systematic errors when trying to recall these stories. He proposed that human memory is an active, constructive process, in which we interpret and transform the information we encounter. We search for meaning, trying to integrate this new information so that it is more consistent with our own personal experiences

Jean Piaget

Swiss theorist who believed children actively explore their world in order to understand important concepts. Children's cognitive strategies change as they mature, and adolescents often use sophisticated strategies in order to conduct their own personal experiments about how the world works.

Noam Chomsky

linguistic who emphasized that the structure of language was too complex to be explained in behaviorist terms. They argued that humans have an inborn ability to master all the complicated and varied aspects of language

Ulric Neisser (1928-2012)

published a book called Cognitive Psychology. The publication of this book served as one of the first comprehensive treatments of cognitive processing, and he was the first to coin the term, cog psyc.

ecological validity

if the conditions in which the research is conducted are similar to the natural setting where the results will be applied.

Cognitive Science

an interdisciplinary field that tries to answer questions about the mind. includes contributions from cognitive psychology, neuroscience, computer science, philosophy, and linguistics

Believe that thinking requires us to manipulate our internal representations of the external world and they focus on these internal representations. Try to connect all academic areas

Pure artificial intelligence

designs a program to accomplish a cognitive task as efficiently as possible, even if the computer's processes are completely different from the processes used by humans.

computer simulation (or computer modeling)

attempts to take human limitations into account. The goal of computer simulation is to program a computer to perform a specific cognitive task in the same way that humans actually perform this task.

computer metaphor

idea that cognitive processes work like a computer

information-processing approach

argued that (a) our mental processes are similar to the operations of a computer, and (b) information progresses through our cognitive system is in a series of stages (one step at a time)

serial processing

the system must complete one step or processing stage before information can proceed to the next step in the flowchart

David Rumelhart

Developed models of learning and thinking that he described as "connectionist network models (also known as parallel distributed processing models of PDP). These were mathematical models of networks between simple processing units (nodes) that could be applied to a wide range of problems in understanding human learning and memory.

sensory memory

a large-capacity storage system that records information from each of the senses with reasonable accuracy

Parallel processing:

simultaneous, with a lot happening at the very same time

This serial information processing model

predicts a linear increase as the size of the memory set increases = each additional digit in a memory set adds about 40 ms of decision making time because you are searching through the whole set.

connectionist approach

argues that cognitive processes can be understood in terms of networks that link together neuron-like processing units;

Also called parallel distributed processing (PDP) approach and the neural-network approach.

cerebral cortex

the outer layer of the brain that is essential for your cognitive processes.

Cognitive neuroscience

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

social cognitive neuroscience

uses neuroscience techniques to explore the kind of cognitive processes that we use in our interactions with other people

For example, researchers have identified a variety of brain structures that are active when people look at a photograph of a face and judge whether the person is trustworthy

brain lesions

refers to the destruction of an area in the brain, most often by strokes, tumors, blows to the head, and accidents

positron emission tomography (PET) scan

researchers measure blood flow in the brain by injecting the participant with a low dose of a radioactive chemical just before this person works on a cognitive task. This chemical travels through the bloodstream to the parts of the brain that are activated during the tasks. While the person works on the task, a special camera makes an image of the accumulated radioactive chemical in various regions of the brain

require several seconds to produce data, so this method does not provide useful information about the time course of processing a stimulus

Functional magnetic resonance imaging (fMRI)

is based on the principle that oxygen-rich blood is an index of brain activity.

When a brain structure becomes active, it requires more oxygen. Within 4 to 6 seconds, blood flow (with its cargo of oxygen) increases to that region

By tracking local changes in blood flow (or oxygen usage), researchers can infer which brain regions are more or less active

less invasive, measures brain activity more quickly, more precise, better resolution

PET scans and functional magnetic resonance imaging provide information about

location. Neither of these techniques provides insight into time course

event-related potential (ERP) technique

records the very brief fluctuations in the brain's electrical activity, in response to a stimulus such as an auditory tone or a visual word. Researchers place electrodes on a person's scalp (usually 32 or 64 electrodes, depending on the system). Each electrode records the electrical activity generated by populations of neurons located in the brain. The ERP technique cannot identify the response of a single neuron but it can identify electrical changes over a very brief period produced by populations of neurons in some region of the brain

ERP technique provides a reasonably precise picture of changes in the brain's electrical potential while people perform a cognitive task

magnetoencephalography (MEG) technique

records magnetic field fluctuations produced by neural activity during the processing of stimuli presented to participants. It provides time-course information roughly identical to the ERP technique. Unlike the EEG/ERP technique, however, it also provides some coarse-grained information about the neural sources responsible for the observed fluctuations.

Edward Tolman

a new behaviorist

Showed the value of cognitive maps. Argued that animals are internally motivated to learn the general layout of mazes by forming what he called cognitive maps, which is an internal representation of the spatial layout of the external environment. They learn regardless of whether they are enforced or not, so it is latent learning (or hidden learning).

Cognitive Revolution

The development of computers led to a rise of cognitive psychology and artificial intelligence. Before this, behavioral psychology was more commonly researched and practiced; cognitive psychology replaced it.

-Noam Chomsky was very influential in beginning the cognitive revolution.

Behavioral Methods

Reaction time (RT):

-Speed of response in a given task

-Varies with complexity of decision to be made

-Longer RT's = more complex decisions

Proportion of Errors:

-Percentage of errors committed on a given task

-Faster RTs produce a greater proportion of errors

-Speed-accuracy tradeoff (faster you go, more mistakes you'll make)

Single-cell recording

a technique by which the firing rate and pattern of a single receptor cell can be measured in response to varying sensory input

showed that there are specialized neurons in the brain that are trained to fire more when things are moving away from your body. So you can study specialized cells that respond to specific directions

Electroencephalography (EEG/ERP)

-EEG is a noninvasive method for measuring electrical activity in the brain by means of electrodes placed on the scalp; the resulting image is an electroencephalogram.

-ERP: event-related potentials: they are derived from EEG measurement of neural activity.

-ERP measures voltage changes in the brain that follow the onset of specific external stimuli

-They do not necessarily require overt motor or linguistic response.

-stimuli can be presented in repetitive sounds (for example) and these stimuli can deviate in pitch, and timing, and the brain can distinguish any sounds that deviate from previous sounds right away.

Transcranial Magnetic Stimulation (tms)

changes activity in the cerebral cortex by generating strong magnetic pulses over the skull.

recency effect

tendency to remember words at the end of a list especially well

Sensation

reception of stimulation from the environment and its initial encoding into the nervous system.

-info: visual, auditory, tactile, olfactory, gustatory

Perception

uses previous knowledge to gather and interpret the stimuli registered by the senses. Uses both top down and bottom up processing

object recognition

When you recognize an object, your sensory processes transform and organize the raw information provided by your sensory receptors. You also compare the sensory stimuli with information that you have stored in your memory.

-depends primarily on shape, rather than on color or texture.

pattern recognition

describes cognitive process that matches information from a stimulus with information retrieved from memory

-identification of a complex arrangement of sensory stimuli

template matching models

assumes every perceived object is stored as a "template" into long-term memory.

- In other words, all sensory input is compared to multiple representations of an object to form one single conceptual understanding.

Used a lot in machine pattern recognition

Problem: not powerful enough for general object recognition (many different styles of M, can't use the same template)

Feature Matching Models

Detect objects by the presence of features. Each object is broken down into features.

-Processes in brain are parallel and distributed (happening in different neural areas)

Recognition by Components Theory (RBC):

complex objects are made up of arrangements of basic, component parts: geons. Recognition involves recognizing object elements (geons) and their configuration/relationship.

Problems for RBC: structure description is not enough (similar objects shapes, whats a human whats an ape), also need metric information to distinguish between similar objects. Doesn't discuss color, and texture

viewpoint invariance

the ability to recognize an object seen from different viewpoints

-The same geons can be recognized across a variety of different perspectives.

criticisms of models of recognition

information is contained strictly on the information contained in the stimulus

-data/stimulus driven

-no context

-I can distinguish the same symbol as being B when by A and C, but looks like 13 in the context of numbers

Top-down

use context and general knowledge/context is used to understand stimuli (conceptual processing)

Bottom-up processing

information from the physical stimulus is used to help recognize a stimulus (data-driven processing)

Start with small bits of information and combine them to form perception.

Stimulus constrained perception

change blindness

Failure to notice large changes to objects and scenes:

-Relying too much on top down processing because your brain thinks that things don't change unexpectedly

inattention blindness

Failure to notice the existence of an unexpected item

-Gorilla with ball being passed example

Face Recognition

many psychologists believe that humans are specifically predisposed to identify whole faces

Even drastic compression of faces does not make them unrecognizable.

Human observers are able to handle significant degradations in face images.

-Faces are harder to recognize when upside down

Thatcher illusion (face-inversion effect)

people are much more accurate in identifying upright faces compared to upside-down faces

-we are used to seeing faces in a specific way. Doesn't effect young children who have not spent time seeing faces in a certain way

Memory for faces

recognition of faces is more impaired by inversion than any other kind of stimuli (inverting skyline in chicago doesn't impact recognition)

Configural/Holistic Face Processing

we process faces holistically, that is processing the overall structure of a face, paying little attention to the details (nose, chin). In contrast, we process objects in a more detailed fashion

Prosopagnosia

selective difficulties in recognizing faces due to damage to the temporal lobe.

-A patient may also be able to recognize a face by the person's voice, or by distinctive features such as a mole on a face, or bright red hair color.

Fusiform gyrus

region of the temporal lobe that responds when faces are present in the visual field

distal stimulus

the object as it exists in the environment

-for example, the pen on your desk.

proximal stimulus

the information registered on your sensory receptors—for example, the image that your pen creates on your retina.

retina

(proximal stimulus) covers the inside back portion of your eye; it contains millions of neurons that register and transmit visual information from the outside world.

iconic memory/visual iconic memory

preserves an image of a visual stimulus for a brief period after the stimulus has disappeared

primary visual cortex

located in the occipital lobe of the brain; it is the portion of your cerebral cortex that is concerned with basic processing of visual stimuli.

-First place where information from both eyes is combined

ground

the region that is "left over," forming the background.

ambiguous figure-ground relationship

the figure and the ground reverse from time to time, so that the figure becomes the ground and then becomes the figure again.

-Explanations for this effect: (1) The neurons in the visual cortex become adapted to one figure, such as the "faces." (2) people try to solve the visual paradox by alternating between two reasonable solutions.

illusory contours (/subjective contours)

we see edges even though they are not physically present in the stimulus. We fill in the blanks.

distinctive feature

in visual perception, an important characteristic of the visual stimulus

(feature-analysis theories)

geons

Different three dimensional shapes that combine to form three dimensional patterns

viewer-centered approach

proposes that we store a small number of views of three-dimensional objects, rather than just one view

word superiority effect

we can identify a single letter more accurately and more rapidly when it appears in a meaningful word than when it appears alone or in a meaningless string of unrelated letters

-features of the stimulus are extremely important because word recognition operates partly in a bottom-up fashion.

-The context is important because word recognition also operates partly in a top-down fashion.

schizophrenia

typically does not show intense emotions, and they may have hallucinations. Individuals with schizophrenia tend to perform poorly on many cognitive tasks

have difficulty in perceiving faces and facial expressions

attention

process by which we direct our cognitive resources toward some environmental event in order to gather information about that event.

Stimulus driven factors

exogenous control, uses bottom-up processes

-Incidental

-Salient large objects grab your attention first

example: a bright light catches your eye.

Goal directed factors

endogenous control, top-down processes

-Intentional/goal driven

example: looking for a stop sign

Eye tracking studies

evaluation of eye fixation and movement

-tell us which information is attended to. Our eyes are drawn both by top-down and bottom-up

fixations

short pauses on points of interest

-200-300ms , information is acquired

Saccades

extremely rapid eye movements between fixations

Selective attention

requires people to pay attention to certain kinds of information while ignoring other ongoing information. Three types: dichotic listening, stroop effect, and visual search

Dichotic listening

studied by asking people to wear earphones; one message is presented to the left ear, and a different message is presented to the right ear. Typically, the research participants are asked to shadow the message in one ear. That is, they listen to that message and repeat it after the speaker.

In the second conversation people paid very little attention. They did not notice when the language changed but did notice when the gender of the speaker changed.

people can process only one message at a time. However, people are more likely to process the unattended message when (1) both messages are presented slowly, (2) the main task is not challenging, and (3) the meaning of the unattended message is immediately relevant

Perceptual selection

process by which people attend to only a small portion of the stimuli to which they are exposed

-decide what to attend to and what to ignore. Due to part of brain called posterior attention network

Inhibitory selection

stop yourself from performing an automatic action, Comes from anterior attention network. (stroop task)

Divided attention

you try to pay equal attention to two or more simultaneous messages, responding appropriately to each message.

-When focusing on two things your speed and accuracy lowers

Dual Task methodology

doing two things at once. How much does task x slows down another task y. The amount of slowing is known as attentional cost

Perfect time-sharing

the ability to pursue more than one task at the same time

-some tasks can be done simultaneously without being slowed down

Disjunctive search

looking for distinct object (colored waldo against a black and white background)

Conjunctive search

looking through similar looking stimuli to find waldo. Takes much more time.

Feature integration theory

we sometimes look at a scene using distributed attention, and we process all parts of the scene at the same time. On other occasions, we use focused attention, and we process each item in the scene one at a time. Treisman also suggested that distributed attention and focused attention form a continuum, rather than two distinctive categories. As a result, you frequently use a kind of attention that is somewhere between those two extremes.

conjunction searches

Visual search process that focuses on identifying a previously requested target surrounded by distractors possessing one or more common visual features with the target itself

Neuropsychology of attention

posterior attention network (parietal part of brain), and anterior attention network (frontal lobe)

Parietal lobes

posterior attention network. Sustaining focused attention. Shifting attention from one location to another to detect a relevant target (visual search tasks)

Frontal lobe

anterior attention network. Responsible for controlling and directing attention. Inhibitory selection (stroop task)

Hemispatial neglect

cause : often a stroke that interrupts the flow of blood to the parietal lobe that is critical in attention and selection

Symptoms: failure to acknowledge objects in the field contralateral to the lesion (opposite side)

Visual neglect syndrome

can be object-based. They neglect the left side of the object, rather than the left side of the space.

Treatment: provide a point of reference for a person so that they have to focus on the left side.

cocktail party effect

Have you ever attended a social gathering when you are surrounded by many simultaneous conversations? Even if you are paying close attention to one conversation, you may notice if your name is mentioned in a nearby conversation.