Cognitive Psychology Exam One

What is cognitive psychology?

The scientific study of the mind and mental functions

Thinking, memory

Why does cognitive psychology matter?

The amount of behaviors we could improve if we understood the mind better

The problem in cognitive psychology

We understand input and output, but not what is happening the brain in the middle of these two processes

Mind as Computer Similarities

Take in and process information, unit of thought is a neuron and unit of processing is a transistor

A computer is better at what compared to a brain?

Math, exact memory, and precision

The brain is better at what than a computer?

Vision, inferences, creativity

Challenge for Cognitive Psychology

The mind is not observable

Observing the Output

We can observe the output or products of the mind (behavior)

Some general solutions to not being able to observe the mind (Three of them)

Introspectionism, Behaviorism, Cognitivism

Introspectionism is

The examination of one’s conscious thoughts and feelings (Wundt and Titchener)

Titchener believed if the physical world could be broken down to its smallest parts, so could the mental world (the apple)

Benefits of Introspection

Standardized experimentation (controlled environment), introspectionists were meticulously trained

Problems with Introspection

Difficult to verify (private events), observe the end product and not the process itself

The Behaviorist Solution

Only look at observable behavior, behavior can be objectively measured and thoughts cannot.

The environment determines behavior so there is a lack of free will

Classical Conditioning (Ivan Pavlov)

Learning procedure where neutral stimulus is paired with a biological response

Watson (Little Albert) Response to Introspectionism

Psychologists should study only that which is observable, consciousness is not suitable for study, conditioned responses are the basic building blocks of all behavior, the goal of psychology is the prediction and control of behavior

Skinner and Operant Conditioning

Behavior will occur more often if they are followed by reward

Complex behaviors come about through the reinforcement of simpler behaviors

Benefits of Behaviorism

Importance of the environment and biological processes (hunger, sleep) on behavior

Made psychology more quantitative

Less participant and experimenter bias

Problems with Behaviorism

1: Can’t account for creativity and diversity of human behavior (Chomsky shows how people use creative language even if it isn’t rewarded)

2. Limiting science to observable things is a bad idea

3. Can’t account for internal cognitions

4. Same behaviors may be the result of multiple stimuli

5. Participants can learn without reinforcement (Albert Bandura and the Bobo dolls)

Main error of behaviorism

Not that the environment doesn’t matter, rather behaviorism’s error was that it is the only thing that matters

The Cognitive Approach

Infer what’s going on inside

Ebbinghaus (he is the one who made the Ebbinghaus forgetting curve)

First major study of memory and used self as only subject

Cognitive Revolution

Switch from pure behaviorism to the study of behavior and cognitions in understanding the human mind

Information Processing Perspective

Information = sensory data coming into the system

Representation = symbol for an entity in the real world

Processes = storage / manipulation / transformation of representations

Behavioral Methods in Cognitive Psychology

Reaction time, eye tracking, survey/online data collection

Mental chronometry

The study of the time course of mental processes

Information Processing Stages

Each stage receives information from the previous stage, transforms the information, sends the information to the next stage

Reaction time: Simple detection task

Raise your hand when you see a red or green light

Signal → detection → Response

Reaction time: Choice task

Raise Left for red light, Raise Right for green light

Signal → detection → decision → Response

Different choices = different reaction times

Subtractive method to use the info from the first task and the second task to isolate how long “making a choice or decision’ takes

Signal → detection → decision → Choice RT (reaction time) 285 ms

Signal → detection → Detection RT 197 ms

---

Duration of the decision stage = 88ms

Subtractive method: Problems

1. Assumption of Pure Insertion (all stages remain the same when the new one is added)

• Adding the decision stage may influence another stage

2. Assumption of additivity (the duration of all stages add together to yield the reaction time)

• Stages might operate in parallel

3. Assumes you already know what the stages are

Donders’ Key Contributions (RT)

Idea: you can identify and measure mental processes

Technique: the reaction time procedure

Shepard & Metzler Mental Rotation Task

Presented with 1600 trials of line drawn objects and pulled a lever when you determined the same or different

Depth pairs were more difficult (look into this)

What does reaction time tell us about the mental rotation task?

We create a mental model of objects in our head and then manipulate them as if we are actually rotating real life objects

Even modern RT tests aren’t perfect

Differential experience can influence reaction times

Eye tracking uses?

Infrared technology to examine where a person is looking (thus, attending)

Pros of Eye Tracking

• Can be used to collect many types of data (reaction time to fixate on object, total amount of looking, number of fixations, pattern of attention, pupil dilation)

• Can be used passively without training or instruction (good for nonverbal participants, cross-cultural research)

Problems with eye tracking

• Looking at something doesn’t mean that we are giving it our real attention or our real understanding

• Cannot track peripheral vision

• Observer effects

Surveys

Amazon Mechanical Turk (mTurk)

• Turk Workers accept assignments for minimal amount of $)

Benefits of Online Data Collection

• Lots of additional data is collected

• Locate a more varied (or more specific) population

• Data is collected very quickly and cheaply

• Aspects of normal design can be automated (can randomize questions, counterbalance tasks, assign conditions)

Problems with Online Data Collection

• Issues with participant attention

• Issues of deception and lying

• Repeated exposure to tasks

• Sampling bias

• Computer systems vary

Neuroscience: Structural and Functional (Physiology)

McCabe & Castle: Seeing is believing

This is the brain scan article

Common Assumptions in Neurocognition

• Cognition is a product of the brain

• Understanding the brain and its organization is useful for assessing cognitive theories

Structural Techniques

Look at the structure of the brain (anatomy) at one moment in time

X-rays: pictures on film (2d) Can detect bone structures

CAT scans: multiple x-rays from different angles (3d) Can detect brain structures

Magnetic Resonance Imaging (MRI)

Magnetic Resonance Imaging (MRI)

Takes still images of brain anatomy in higher detail

• Slower than CT and not a good option for those with metal in their body

Uses magnets to line up our protons and then bounces radio waves off them

• The signal is collected, digitized, and stored in a computer

Functional Techniques: Looks at how the brain functions - where and when (4)

Examples:

fMRI, PET, EEG/ERP, TMS

fMRI Information

Similar to MRI, only can study changes in the brain

• Also uses magnet & radio waves for structural information: but utilizes the fact that ‘oxygen rich’ blood reacts differently & oxygenated blood releases a stronger radio signal bounce-back than deoxygenated blood

• If we assume more oxygen = more brain activity, then the places where the signal is stronger is what part of the brain we use

Benefits of fMRI

• Great ability to locate what exact area of the brain is most ‘active’ (has most oxygenated blood)

• Okay (but not great) temporal resolution (within about 2 seconds)

• Completely non-invasive

Problems with fMRI

• Practical constraints (can’t move, very loud

• Money constraints

• Is an indirect measure (blood flow, not neurons)

• Uses a “subtraction method” with normalized baselines

fMRI Subtraction Method

Stimulation State - Control State = Difference

PET Scan and how it works

• Inject radioactive material into the patient

• As radiotracer breaks down it emits positively-charged particles

• Computer picks up particles, turns into an image

• Can track things like neurotransmitters (dopamine, serotonin)

PET Pros and Cons

Pro:

• Can trace more than just oxygen based on type of radioactive material (Alzheimer’s, tumors, epilepsy)

• Isn’t influenced by movement

Cons:

• Radioactive materials being injected

• Pictures often fuzzy

• Bad temporal resolution (1 min or more)

EEG scan is

• Neurons in our brain constantly give off electricity

• This electricity passes through our scalp

• Electrodes placed on the scalp amplify and record this electricity

Event-Related Potentials

Cuts the ongoing EEG signal into small parts related to a certain stimulus, and averages them together

Pros and Cons of EEG / ERP

Pro:

• Amazing temporal resolution (We can see exactly when certain activity is happening)

• Very non-invasive (can use with kids, primates, elderly)

• Cheaper than scanners (MRI, fMRI)

Cons:

• NO movement allowed

• Not good at finding location

• Changes dramatically with age

Transcranial Magnetic Stimulation (TMS)

• Magnetic coil placed near head of participant

• Sends pulses through the skull to the brain (can either excite or inhibit the targeted brain area)

Brain scan Overview

For neuro methods, the main takeaway:

• PET/fMRI/TMS: Better for localization

• EEG/ERP/MEG: Better for timing

The size of a neuron is ______ the same

Strong _________ will increase the rate of firing of a neuron

always

stimulation

The cerebral cortex is called the brain ________

bark

The cerebellum and brainstem is the ______ part of the brain

oldest

It controls basic functions like breathing, heartbeat, posture, motor coordination

Frontal Lobe is evolutionarily one of the _______ areas

youngest

Primary motor projection areas

Less precision = _______ brain area

Greater precision = _________ brain area

smaller

more

Photoreceptors are the r___ and the c____

Rods and Cones

Rods are for the darkness

lower sensitivity, lower acuity, color-blind

The Fovea and Blind Spot

Fovea: located in a small pit at the back of the eye, responsible for sharp, clear vision

Blind spot: located where the optic nerve leaves the back of the eye, not problematic for binocular vision

The visual system includes parallel processing in the visual system in two parts: object l_____ and object s____ and i_____

location

shape and identity

The visual system:

The what system

The where system

The what system: occipital-temporal pathway

The where system: occipital-parietal pathway

Visual agnosia is damage to the “____” system

what

Two major phenomena that a theory of perception must be able to explain:

Lack of Correspondence

Paradoxical correspondence

Lack of Correspondence: perception doesn’t equal reality (visual illusions)

Paradoxical correspondence: Perception = Reality

Paradoxical Correspondence: P_____ C____ are an example of paradoxical correspondence

Perceptual constancies (size constancy, color constancy, shape constancy)

Theories of Object Perception

Direct perception (bottom-up theory)

Constructivism (top-down and bottom-up theory)

Direct Perception (Stimulus → Eye → Visual Cortex → Representation)

Environment provides all necessary cues

Stimulus information is unambiguous

Our brains are pre-wired to pick up cues

Template-Matching Theory

Take in stimulus, compare it to exact patterns (templates) stored in memory

We would need a LOT of templates

feature detection theories (word recognition and recognition by components -rbc-)

Word recognition = feature nets (bottom-up)

• Goes from lower level (features and nodes) to higher levels (words and sentences)

If features are “warmed up” they require less activation to fire

How to “warm up” a node?

Recency and familiarity