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