Perception. Memory, and Thought unit 1

Mind

system that creates mental representations of the world & controls mental functions like perception, attention, memory, emotions, language, deciding, thinking, & reasoning; It's a system that creates representations of the world so that we can act within it to achieve our goals

Cognition

The mental processes involved with perception, attention, memory, language, problem-solving, reasoning, and decision making

Cognitive psychology

Scientific study of mental processes involved in perception, memory, attention, language, problem-solving, reasoning, and decision making

Franciscos Donders

Performed first cognitive psych experiment; studied simple reaction time and choice reaction time to see how long it takes to make a decision.

Reaction time

Time it takes to react to a stimulus, usually determined by measuring time between presentation of stimulus and response to it

Simple reaction time

Time to react to the presence or absence of a single stimulus (as opposed to having to choose between a number of stimuli before making a response)

Choice reaction time

Time to react to one of 2+ stimuli

Wilhelm Wundt

Founded the first lab for psych and had a structuralist approach to psychology

Structuralism

Explained perceptions as the adding up of small, elementary units called sensations (like a periodic table of the mind)

Analytic introspection

Procedure used by early psychologists in which trained participants described their experiences and thought processes in response to stimuli

Hermann Ebbinghaus

Investigated how long it takes to forget learned information, which was measured by “savings”

Savings

Determines magnitude of memory left from initial learning; high savings correlates to high memory

Savings curve

Plot of savings vs time after original learning; generally shows that people forget the most within two days of original learning, then it levels out

William James

Did not conduct experiments but instead reported observations of his own experiences; he concluded that paying attention involves withdrawing attention from other, less important stimuli. Also founded functionalism, which is the study of the practicality or purpose of behavior and mental processes.

John Watson

Founded behaviorism

Behaviorism

“Observable behavior provides the only valid data for psychology”; This school of thought made consciousness and other unobservable mental processes not worthy of study

Downside to analytic introspection

Requires highly trained participants and experimenters, results vary person to person, and difficult to verify because it is interpreted via invisible inner mental processes

Little Albert Experiment

Participant was presented with a loud noise every time a rat came close [with the participant initially liking rats] soon, the participant would scurry away whenever a rat came through even without a loud noise

Classical conditioning

Pairing a neutral stimulus with a stimulus that elicits a response causes the neutral stimulus to elicit that response

BF Skinner

Studied operant conditioning

Operant conditioning

How a behavior is strengthened by positive reinforcers or withdrawal of negative reinforcers

Edward Chace Tolman

Behaviorist who tried to infer mental processes via cognitive mapping

Cognitive map

mental conception of a spatial layout

Cognitive revolution

Shift in psych from behaviorism approach to the approach to explain behavior in terms of the mind, which brought the information-processing approach to study the mind

Scientific revolution

Occurs when there is a shift in thinking from one scientific paradigm to another

Paradigm

System of ideas, which guide thinking in a particular field

Paradigm shift

Shift in thinking from one system of ideas to another; a scientific revolution inherently involves this

Information processing approach

Mind described as processing information in a sequence of stages, which brought on studying how well people focus their attention on some information while other information is presented at the same time

Broadbent’s diagram of the mind

Input→Filter (lets message in)→detector (records information)→to memory

John McCarthy

Wondered if the human mind could be mimicked by computers, so he coined the term “artificial intelligence”

Artificial intelligence

Ability of a computer to perform tasks usually associated with human intelligence

What is the magic number for memorizing a sequence of information?

7 ± 2

Ulrich Neisser’s cognitive psychology

Describes how information is taken in by vision and held in short term memory; includes higher mental processes like thinking, problem-solving, and long term memory, but lacks information on physiology and knowledge of higher mental processes

Atkinson and Shiffrin’s model of memory

Input→Sensory memory (holds info for a fraction of a second)→Short term memory, which can either be output and/or rehearsed OR → long term memory (or long term memory could go back to short term)

Tulving’s memory model

Within long-term memory, there’s episodic memories (life events), semantic memories (facts), and procedural memories (physical actions)

Neuropsychology

The study of behavioral effects of brain damage in humans

Electrophysiology

Techniques used to measure electrical responses of nervous system

Brain imaging

Techniques like fMRI that results in pictures of brain that represent its activity; that activity is measured in response to specific cognitive tasks

Significance of pet scans

Made it possible to see areas of the brain activated during cognitive activity

Significance of fMRI

Brought another revolution within cognitive psych→further consideration of higher mental processes, large amount of physiological research, and high amount of research in “real-life” scenarios

How did the cognitive revolution happen?

1. Chomsky’s critique of Skinner’s book Verbal Behavior
   2. Intro of digital computer and the idea that mind processes in stages
   3. Cherry’s attention experiments and Broadbent’s intro of flow of the mind diagrams to depict processes of attention
   4. Interdisciplinary conferences at Dartmouth and MIT

What is the conditioned response?

In classical conditioning, an automatic and uncontrollable response to a specific stimulus

Difference in operant and classical conditioning

Operant=voluntary response; classical=involuntary response

What is required to make both experimental groups nearly the same?

Random assignment and sampling

Between-subjects design

1 group is exposed to 1 condition respectively

Within-subjects design

1 group exposed to both conditions; advantage=low variability because people are most similar to themselves in their responses; disadvantage=not always applicable because people in the experimental groups can’t always be naive to what’s happening

Cognitive neuroscience

Field concerned with studying neural basis of cognition

Levels of analysis

A topic can be understood by studying it at a number of different levels/approaches in a system

Nerve net theory

Now unsupported; network of continously interconnected nerve fibers (highway system, a one-way street)

Neurons

Cell that is specialized to receive and transmit information in the nervous system

Ramon y Cajal’s neuron doctrine

Idea that individual cells (neurons) transmit signals in the nervous system, and that these cells are not continuous with other cells as opposed to the other theory

Cell body

Part of a cell that contains mechanisms that keep the cell alive; in some neurons, the cell body and dendrites associated with it receive info from other neurons

Dendrites

Structures that branch out from the cell body to receive electrical signals from other neurons

Axons/nerve fibers

Part of the neuron that transmits signals from the cell body to the synapse at the end of an axon

Synapse

Space between the end of an axon and the cell body or the dendrite of the next axon

Neural circuits

Group of interconnected neurons that are responsible for neural processing

Receptors

Specialized neural structures that respond to environmental stimuli like light, mechanical stimulation, or chemical stimuli

Microelectrodes

Small wires that are used to record electrical signals from single neurons

Recording electrode

When used to study neural functioning, a very thin glass or metal probe that can pick up electrical signals from single neurons

Reference electrode

Used with a recording electrode to measure difference in charge between the two electrodes; generally placed where the electrical signal is constant, so any change in charge between the two electrodes reflects happening near tip of the recording electrode

Resting potential

Difference in charge between the outside and inside of a nerve fiber when the fiber is at rest and no other electrical signals are present

Nerve impulse/Action potential

An electrical response that is propagated down the length of an axon

Neurotransmitter

Chemical that is released at the synapse in response to incoming action potentials. Allows a signal to cross the gap from the end of an axon to a dendrite or cell body of another neuron

Electrical signals in a neuron represent—

Intensity of a stimulus

Principle of Neural Representation

Everything a person experiences is based on representations in that person’s nervous system

Feature detectors

Neurons that respond to specific visual features, such as orientation, size, or more complex features that make up environmental stimuli

Experience-dependent plasticity

Mechanism that causes an organism’s neurons to develop so they respond best to the type of stimulation to which the organism has been exposed; the structure of the brain is therefore changed and molded by experience.

Visual cortex

Area in occipital lobe that receives signals from eyes

Temporal lobe

Lobe on the side of the brain that contains mechanisms responsible for understanding language, memory, hearing, and vision

Hierarchical processing

Processing that occurs in a progression from lower to higher areas of the brain

Sensory code

How neural firing represents various characteristics of the environment; process by which nervous system converts physical stimuli from the environment into neural signals, which are then interpreted by the brain to create perception

Specificity coding

Representation of a specific stimulus by the firing of neurons that respond only to that stimulus (likely incorrect because there’s too many different stimuli to have 1 neuron dedicated to 1 object)

Population coding

Neural representation of a stimulus by pattern of firing of a large number of neurons. Generally more accepted because that means a large number of stimuli can be represented.

Localization of function

Location of specific functions in specific areas of the brain; e.g. specialized areas process info involved in perception of movement

Cerebral cortex

3mm thick outer layer of the brain with mechanisms responsible for higher mental functions like language and problem-solving

Neuropsychology

Study of behavior of people with brain damage

Cortico equipotentiality

Idea that was popular in the 1800s that the brain operates as a indivisible whole, as opposed to operating based on specified areas

Broca’s area

Area in frontal lobe associated with production of language

Broca’s aphasia

Condition associated with damage to the broca’s area; characterized by labored ungrammatical speech and difficulty understanding some types of sentences

Wernicke’s area

Area in temporal lobe associated with understanding language

Wernicke’s aphasia

Condition caused by brain damage to Wernicke’s area that causes difficulty in understanding language. Fluent and grammatically correct, but incoherent speech

Occipital lobe

Lobe in the back of the brain associated with analyzing incoming visual information

Parietal lobe

Lobe at the top of the brain that contains mechanisms responsible for sensations caused by stimulation of skin and also some aspects of visual information. 

Frontal lobe

Lobe at the front of the brain that does higher functions like language and motor function

Prosopagnosia

Condition caused by damage to the temporal lobe characterized by the inability to recognize faces

Double dissociation

Situation when a single dissociation is demonstrated by 1 person, and opposite type of single dissociation can be demonstrated in another person (Person 1 = Function A, damaged Function B) and person 2 = function B, damaged function A)

Importance of double dissociation

It shows we can conclude functions A and B are served by different mechanisms and operate independently of one another

Functional magnetic resonance imaging (fMRI)

Brain imaging technique that measures how blood flow changes in response to cognitive activity.

Voxels

Small cube-shaped areas in the brain used in the analysis of data from brain scanning experiments; like pixels in a digital photo

Fusiform face area (FFA)

Area in temporal lobe that contains many neurons that respond selectively to faces

Parahippocampal Place Area (PPA)

Area in temporal lobe that contains neurons that are selectively activated by pictures of indoor and outdoor scenes; importance=spatial layout

Extrastriate Body Area (EBA)

Area in temporal cortex activated by pictures of bodies and parts of bodies, but not by faces or other objects

Excitatory neurotransmitter

Makes the next neuron more likely to fire

Inhibitory neurotransmitter

Makes the next neuron less likely to fire

Synaptic vessicles

Vessels for the neurotransmitter

Multidimensional nature of cognition

Refers to the fact that even simple experiences involve combinations of different qualities

Ex of the multidimensional nature of cognition 

Seeing a face: 
1. Emotional aspects (smiling, so she’s probably happy)

2. Where are they looking?

3. How parts of the face move (watching lips move to understand speech)

4. How attractive is the face?

5. Is the face familiar?

Distributed representation

Occurs when a specific cognition activates many different areas of the brain

Episodic memories

Events in one’s life

Semantic memories

Facts