Psyc 230 Final Exam

Deductive Reasoning

Determining whether a conclusion logically follows from premises

Syllogism

Whether or not a conclusion from two premises is valid or not

Syllogism broken down (2 parts)

1. Two statements called premises

2. Third statement called conclusion

Categorical Syllogism

Describes the relation between two categories using all, no, or some

Examples:

Validity vs Truth (Don’t confuse)

Syllogism is valid if conclusion follows logically from its two premises

If two premises of a valid syllogism are true, then the syllogism’s conclusion must be true

Valid but not true ^^^^^^

Belief bias (Judging Validity)

The tendency to think that a syllogism is valid if its conclusions are believable

Believable conclusions that are invalid are more acceptable than unbelievable conclusions that are valid.

Conditional syllogisms

“if p, then q”

1. If it rains, then my run will be on the treadmill

2. It rains, therefore my run is on the treadmill

The way it’s worded makes it easier

Watson Selection Task

Version 1:

You are given cards with a letter on one side and a number on the other. The statement is : “If a card has a vowel on one side, it has an even number on the other”

You only need to flip: The E card (to see if there’s an even number) and the 5 card(to see if there’s a consonant)

Version 2: You’re a cop, and there are cards with drinks and ages. The rule is: “you can drink beer only if you’re 21 or older”.

You only need to flip: The Beer card(to see if they’re over 21) and the 17 card (to see if they are drinking underage)

Conclusion: We are better at completing the task when framed as a deontic conditional (that has to do with permissions/entitlements, etc.)

Expected Utility Theory

People choose the option that gives them the highest expected utility, measure of value they expect from each possible outcome

• People are basically rational

EX:

Bet 1: 50% chance to win $100 (utility = 100) and 50% chance to lose $50 (utility = -50)

Bet 2: 100% chance to win $30 (utility = 30).

Expected utility for Bet 1: 0.5 X 100 + 0.5 X -50 = 25 expected utility

Expected utility for Bet 2: 1 X 30 = 30 expected utility

EUT would say that we would choose bet 2

Deal or no Deal Hypothesis

If things are going well, we expect people to accept a deal

If things are not going well, we expect people not to accept a deal

Status Quo Bias (Decision Making)

Tendency to prefer things to stay the same and not change

Framing Effect (Decision Making)

Risk-Aversion strategy used when problem is stated in terms of gains

Risk-taking strategy when problem is stated in terms of losses

People’s choices are influenced by how info is presented

Example:

Positive Framing: “90% of people survive during this surgery”

Negative Framing: “10% of people die during this surgery”

Expected vs actual emotions coinflip test (loss aversion)

A coinflip has two possible outcomes (winning $5 or losing $3)

Before the flip: People expect that winning $5 will make them happier than losing $3 will make them sadder. They anticipate a positive overall outcome

After the flip: The actual results show people feel a stronger negative emotion from losing $3 than the positive emotion they feel from winning $5

Emotion affect on decision making study (Computers vs Humans)

People reject low offers because they are angry about unfairness, more so when the offer is made by a human.

• Higher acceptance rates for low offers when computer

Clouds make nerds look good (Simonsohn)

On cloudy days, admissions counselors prioritize academics

On sunny days, admissions counselors prioritize social stuff

Medication choices analysis

When patients are presented with prescribing medication or nothing, they are less likely to do nothing than when prescribing two options of medication vs nothing

C-Section Recommendations

Doctors are more likely to recommend C-sections if they follow routine cases, compared to when it’s an isolated case

Organ Donation (Status Quo Bias)

People are more likely to be organ donors if they have to opt out rather than opt in

• Stick with default

Decision Fatigue

Making decisions and exercising willpower = more impulsive or no decisions

Ex: Israeli Parole Board

Early Morning Cases: Judge gives 70% parole

Late in the day: Judge gives 10% parole

Test of the Mardi Gras Theory

Mardi Gras Theory: After exerting willpower in one task, people may have less willpower to subsequent tasks

First: Willpower task,

Then: Another willpower task

Finding: People are more likely to choose sugary options when their willpower is already depleted from a previous task

Semantics

Meanings of words and sentences

Syntax

Rules for combining words into sentences

3 Ways of Studying Cognition

1. Experimental psychology: Accuracy and Reaction Time

2. Cognitive Neuropsychology and Neuroscience

3. Computer Modeling

Cognition

Mental processes involved in acquiring knowledge and understanding

History of Cognitive Psychology

Early 1800s: The mind can’t study itself

Later 1800s:

• Donders: RT of decision making

• Ebbinghaus: Time course of forgetting

• Wundt and James

Early 1800s:

• Watson: Behaviorism

• Skinner

Mid 1900s:

• PC’s and Al

• Chomsky

• Neisser: 1st text book

Donders: RT of decision making

1st: Press J when light goes on

2nd: Press J for left light, K for right

What is being measured with the time between the two? Time to make a decision

Refute of Behaviorism (Tolman)

Rats at varying locations

Group 1: Always turned right for reward

Group 2: Reward always at location “B”

Behaviorists would think that group 1 would win

Actual: Whenever reward was in the same location

Neural substrates of cognition

Perception

Attention

Memory

Language

Decision-Making

Problem Solving

Consciousness

Are neurons physically connected?

NO, they have a synapse gap

Reticular Theory: There are connected WRONG

Neuron Doctrine: They aren’t connected RIGHT

• They come in many different varying in shape, size, connections, etc

3 main parts of a neuron

1. Dendrites: Many, receive the signal

2. Cell Body

3. Axon: One, propagate the signal onto the next neuron

How do electrical signals travel?

From neuron to neuron, converting the stimulus into the perception of the stimulus

How does the signal travel from neuron to neuron? (4 Steps)

1. Neuron receives a signal that is in either a chemical form or a physical form

   • Receptor cells (sensory neuron)

   • Interneurons

2. Sodium diffuses down the dendrites and cell body

3. The electrical signal is activated and travels quickly down the axon to the axon terminals

   • Only if the current is strong enough when it reaches the axon

4. This causes the release of neurotransmitters at the synapse and the process starts all over in the next neuron

Action Potentials facts

• A process that only occurs in axons

• Can travel at speeds up to 100 meters/sec

• Remain constant in strength as they move, so signals are transmitted without loss

Resting Potential

-60 to -80 millivolts (relative extracellular space)

Steps in Action Potential (6)

1. Na+ channels open (Polarization)

2. K+ channels open (Hyperpolarization)

3. Na+ channels become refractory

4. K+ continues to leave cell

5. K+ channels close, Na+ channels reset

6. Extra K+ outside diffuses away (Refractory Period)

   

What does the ion pump do?

Restores the normal distribution of Na+ and K+ ions

What happens when sodium ions get inside one part of an axon?

That region of the axon opens its sodium channels allowing more sodium to enter to enter the intercellular space

Myelin Sheath

Wrapped around axons, making the ion channels unable to open

• Speeds up neural transmission

• Saves energy

• No action potentials, passive current

All or None Law (Action Potential)

Every action potential is the same, either happens or doesn’t

Intensity Coding

How strong is a stimulus?

Stronger stimuli have higher firing rates (more action potentials)

Weaker stimuli have lower firing rates (less action potentials)

Quality Coding

What type of stimulus is it?

• Which specific neurons respond to a particular stimulus

• Sensory = different types of receptors (light, sound)

Feature Detectors in the visual system

Different qualities activate different neurons

Features are important for conscious perception:

• Experience dependent plasticity: Cats in vertical bin during childhood don’t respond to horizontal light

Temporal Cortex Neurons

Neurons respond to more and more complex stimuli

Specificity coding

Single neuron responding to one stimulus

Sparse Coding

Some neurons within a population fire different amounts for different stimuli

Population coding

All of the neurons within the population fire some amount for different stimuli

Neuronal Recording

A microelectrode can be inserted into the axon of the cell so the firing rate of that cell can be recorded

• Measures electrical activity of neurons

What is the benefit of myelination of an axon

Signal can travel faster, less energy used for neural firing

If sodium is blocked in action potential…

It can’t work

Neuropsychology

The study of how brain injuries or illnesses affect psychology

Single Cell Recording

Measures the electrical activity of a single neuron

Good for Timing and Location

Limitations of single cell recording

Hard to pin point specific cells and what produces activity in those cells

• The behavior of cells is more than just the sum of its parts

• Most cases cannot be done in humans

Electroencephalogram (EEG)

Can tell us general brain state

• Scientists are learning more about how specific oscillatory activity is related to specific cognitive ability

• Without further processing, EEGs cannot give you specific information on neural responses to specific stimuli

• We need to make ERPs from them

Event related potentials (ERPs)

The EEG is cut up and the pieces are averaged together so we can get rid of the random noise and see the neural activity that is associated with a certain stimulus of interest

• Often used to explore the time course of attentional allocation

• Subjects are instructed to direct their attention to the side that the arrow is pointing to

• Good at timing, bad at location

  

Attentional allocation effects…

Behavior AND neural processing

Difference between ERPs and EEGs

EEGs measure the overall electrical activity in the brain by capturing continuous brain waves

ERPs are a subset that focuses on brain responses to specific stimuli or events

Magnetic Resonance Imaging (MRI)

The density of hydrogen atoms is different in different types of brain matter, which allows us to see the different structures of the brain

• Image of the structure of the brain

Functional Magnetic Resonance Imaging(fMRI)

Images the function of the brain

• Uses the magnetic properties of hemoglobin

Allows multiple stimulus types to be presented in succession. Measures time dependent fluctuations in oxygen

Plots of hemodynamic response to static and moving stimuli sow differences in two distinct brain regions

Is fMRI an indirect or direct measure of neuronal activity?

Indirect

Where is vision located in the brain

Occipital lobe, primary visual cortex

Where is hearing located in the brain

Temporal Lobe

Where is higher order thinking in the brain?

Frontal Lobe

Where is motor control in the brain?

Frontal lobe, precentral gyrus

Where is somatosensory processing in the brain?

Parietal lobe, postcentral gyrus

Where is language in the brain

Left Hemisphere

Phineas Gage

Gunpowder on railroad accident, suddenly became angry and upset

• Damage to his frontal lobe, explained impulsive behavior

Map of the brain (labeled)

Sensory Homunculus

Visual representation of the somatosensory cortex in the parietal lobe , shows how different parts are represented in the brain

• More sensitive = more space (hands and face)

• Less sensitive = less space (legs)

What is tonotopic or cochleotopic mapping?

Organization of sound frequencies in the brain’s auditory cortex, which is in the temporal lobe

• Low frequencies mapped to one region and high frequencies to another

Divisions of the cerebral cortex

Auditory Processing = temporal lobe

Somatosensory and Spatial Maps = Parietal Lobe

Visual Processing = Occipital Lobe

Motor/movement and Executive Functions = Frontal Lobe

Modularity Processing

Different areas of the brain are specialized for specific functions

Distributed Processing

Different regions of the brain work together to process information

Central principle of cognition

Most of our experience is multidimensional

• In addition to localization of function, specific functions are processed by many different areas of the brain

• May seem to contradict the notion of localization of function, but the concepts are complementary

Structural Connectivity

Physical pathways or networks of fibers connect different brain regions

6 functions determined by resting-state fMRI

1. Visual

2. Somato-motor = Movement and touch

3. Dorsal Attention = Attention to visual stimuli and spatial locations

4. Executive Control = Higher-level cognitive tasks involved in working memory and directing attention during tasks

5. Salience = Attending to survival-relevant events in the environment

6. Default Mode = Mind wandering, and cognitive activity related to personal life-story, social functions, and monitoring internal emotional states

   

Perception

The experiences resulting from stimulation of the senses

The Perceptual Process

1. Environmental stimulus

2. Stimulus on the receptors

3. Transduction

4. Processing

5. Perception

6. Recognition

7. Action

Sensation vs Perception (Tong)

Uses a single bistable image (face or house) presented to each eye, and the brain alternates between perceiving a face or a house

• Changes happen when activity is related to perception, not sensation

Sensation

Raw sensory input

What does the FFA recognize and process

Fusiform Face Area, processes faces

• Located in the temporal lobe

• Related to the PPA

What does the PPA recognize and process

Parahippocampal place area, processes places and scenes

• Located in the temporal lobe

• related to the FFA

Blue Dress vs Gold Dress Explained

We can’t tell what the ambient lighting is, so we take a biased guess

• Morning Larks = White/Gold

• Night Owls = Blue/Black

Perceptual Process complicated problem

We are able to recognize things

1. Even when they aren’t exemplars of their categories

2. Even though the stimulus on the receptors is ambiguous (Inverse projection problem)

3. Even when they are blurred

4. And from various viewpoints- our perceptions have viewpoint invariance

Top Down Processing

Using existing knowledge and expectations to interpret new information

Example: Multiple Personalities of a Blob study

Bottom Up Processing

Uses sensory information to understand stimuli

Multiple personalities of a blob study (Top-down processing)

Give participants a blurry blob

The brain uses top-down processing to interpret the image based on surrounding information

What does top-down processing to in speech segmentation?

Helps us understand when one word ends and the next begins

• Ex: MAD GAB

Statistical Learning of Speech Segmentaiton

Process of learning about characteristics of language

• Occurs as young as 8 months old

Study:

2 mins of continuous speech with random stuff: bidakupadotigolabuttupiropadotibidakutupiro

Segmeted words = Padoti, Nonwords = Tigolab

Habituation: Novel are more interesting and require more attention

Finding: Children focused more on part words than whole words

Top-down processing in speech segmentation

Expectation: How we expect to experience pain

• If we explain pain, it is better

• Placebos can decrease pain

Nocebo Effect Study

After surgery, IV in arm, any given pain medication could be or not be given to them

• Baseline pain rating = 66

• No expecation, given drug pain rating = 55

• Positive Expectation: Given drug and knew it, pain rating = 39

• Negative Expectation: Given drug and told they didn’t have it, pain rating = 64

Nocebo Effect: When a person experiences negative side effects (pain) from a treatment that is actually harmless, because they believe it will cause harm

Top-Down Pain Management: Endorphins

Endogenous opioids that inhibit neurons from sending the pain signal. Can be caused by

• Distraction/Placebo

• Thrilling music

• Sex

• Laughing

• Eating Chocolate

• Exercise

• Sniffing Vanilla or Lavender

4 Theories on how we use Top-Down Processing to recognize objects

1. Helmholtz’s Unconscious Interference

2. Gestalts principles of organization

3. Considering Environmental Regularities

4. Bayesian Inference

Helmholt’z unconscious inference (Top-Down Processing to recognize objects)

Likelihood Principle: Assumptions happening rapidly and unconsciously

• We make assumptions based on what we think is most likely

• Least defined out of the 4

Gestalt’s Principles of Organization (Top-Down Processing to recognize objects)

Structuralism (Pre-Gestalt): Sensations combine to make perceptions

Gestalt Said: The whole is not the sum of all parts

Example of Gestalts theory: Modal completion is a perception not made from an actual sensation

Law of Good Continuation (Gestalt’s Principles of Organization)

We tend to continue contours whenever the elements of the pattern establish an implied direction

Law of Simplicity or Pragnanz (Gestalt’s Principles of Organization)

Forms with the most simplicity, regularity, symmetry, and ease of remembrance are most easily understood. People tend to see the interpretation of picture that makes the most sense to them based on logic, intuition, and past experience

Law of Similarity (Gestalt’s Principles of Organization)

We tend to group objects with similar properties (color, shape, texture)

Law of Proximity (Gestalt’s Principles of Organization)

Objects that are positioned close to one another are often seen not as separate parts, but rather as one coherent whole

Law of Common Fate (Gestalt’s Principles of Organization)

We group objects that move in the same direction

This moves and we see a dog

Principle of Common Region (Gestalt’s Principles of Organization)

Elements that are within the same region of space are grouped together