Psych 1 - Midterm 1

For Professsor Ferreira's PSYC 1 Course

Psychology

Provide better understanding of natural intelligence through objective description or mechanistic analysis

Structuralism

• progenitor of western European psychology

• Not objective

Functionalism

Characterize everything we’re doing via functions

Behaviorism

• Addressed failings of structuralism (ie non-objective)

  • Build theories of psychology based on objective observations of stimuli, called “observables,” and the way we respond to them (1910-1950)

    • Want as little inobservable things as possible

Gestalt Psychology

Surroundings are more compelx than individual stimuli

Physiological Psychology

Understand brains/nervous system to study psychology

Cognitive Psychology

Modern Psychology

Reflex

• Automatic response to a specific stimulis

  • Startle Reflex: Defensive response to a sudden unexpected, stimulus

Habituation

When a response to a stimulus diminishes with repeated presentation of the stimulus

Classical Conditioning

• When a neutral stimulus becomes associated with a stimulus

  • EG Pavlov’s Dogs: Person Appearing associated with Food

Original Unlearned Association

• Inherent Response (eg Food → Salivate), can be just about anything

  • Food is Unconditioned Stimulus (UCS)

  • Salivation is Unconditioned Response (UCR)

New Association

• Pairing is formed, once stimulus leads to certain result

  • Conditioned Stimulus: Person appearing

  • Conditioned Response: Salivaton

Extinction

When repeated presentation of a conditioned stimulus without the unconditioned stimulus, leads to the conditioned response to diminish

Spontaneous Recovery

When an extinguished response returns due to the passage of time only

Generalization

When a stimulus that is similar to an already learned stimulus elicits the conditioned response

Discrimination Training

When generalization is limited with further learning so that two different conditioned stimuli come to elicit different conditioned responses

Operant Conditioning

• The learning of new responses

  • EG Cat in a puzzle box searching for a way out, accidentally pushes the open lever; being placed back in the box leads to them repeating the lever push faster and faster

Law of Effect

Responses that produce a satisfying effect are more likely to occur again whereas responses that produce a discomforting effect become less likely to occur

Reinforcer

Things in the environment that increase the likelihood of a behavior

Punishers

Things in the environment that decreases the likelihood of a behavior

Skinner Box

An apparatus for efficiently and precisely eliciting operant learning and measuring operant behavior

Shaping

Successive reinforcement of responses that increasingly approximate a target behavior (“you’re getting warmer”)

Schedules of Reinforcement

• Continuous Reinforcement: When every operant response is reinforced

  • Faster initial response

• Partial Reinforcement: When some but not all operant responses are reinforced

  • Partial Reinforcement Extinction Effect: Learning that requires more trials to extinguish under a partial reinforcement schedule

Types of Reinforcement Schedules

• Ratio: Based on # of responses

• Interval: Based on how much time has passed

Positive vs. Negative Reinforcement

• Positive: Providing reinforcement increases behavior

• Negative: Taking something away increases certain behavior

Punishment

• Any event that reduces or weakens the likelihood of a behavior

  • Positive Punishment: Presenting something unpleasant after a behavior

  • Negative Punishment: Taking away something pleasant (reducing/removing)

Taste Aversion

• Food aversion learning

• A biologically/evolutionary determined special form of learning

  • Protects us from foods we can eat that are poisonous

5 Differences Between C.C. and Food Aversion

• Somewhat similar to classical conditioning but…

  • Lasts much longer

  • Happens with just one trial

  • Much more resistant to extinction

  • Unconditioned stimulus and conditioned stimulus can be separated by a long time

  • Only happens with tastes and smell

Expectancy Effect

The conditioned stimulus leads the organism to expect the unconditioned stimulus, leading to the form of the conditioned response

Support for Expectancy Effect

• Examples:

  • Works best when Conditioned Stimulus precedes the Unconditioned Stimulus

  • Blocking Effect: The Conditioned Stimulus will not come to elicit a Conditioned Response if another distinct Conditioned Stimulus already predicts the Unconditioned Stimulus

Neuron

• Brain cells that transmit electrical signals

  • Function: Send and receive electrical signals from one neuron to another

  • 3 Kinds of Neurons:

    • Sensory: Take information from the world and transmit it to your brain

    • Motor: Take information from your brain and transfer it to your muscles

    • Interneurons: Neurons that send information from one neuron to another

Parts of Neuron

• Cell Body: Includes all standard cellular appartus and nucleus

• Dendrites: Branch-like extensions from cell body, receive signals from other neurons and increase the surface area of the neuron

• Axon: Transmits signals down the length of the neuron

  • Axon Terminals: Send signals to other neurons

• Myelin Sheath: Provides nutritional capabilities to the cell, causes signals to transmit faster down the axon

Neural Communication

• Synapse: Gap between the axon terminals of a sending neuron and the dendrites of a receiving neuron

5 Steps of Neural Communication

• 1. Sending neuron “fires” action potential (all or more electrical signal that travels down the axon of a neuron)

• 2. Action potential arrives at the axon terminals

• 3. Axon terminals release neurotransmitter into the synapse

  • Neurotransmitter: Chemical that affects the activity of another neuron or muscle

• 4. Neurotransmitter floats across the synapse to the dendrites of the receiving neuron

• 5. If the receiving neuron receives enough neurotransmitters, it fires its action potential

Nervous System

• All of the neurons in your body

• Consists of two components:

  • Control Nervous System (CNS): Brain and Spinal Cord

  • Peripheral Nervous System (PNS): Nerves (bundles of axons outside the central nervous system)

2 Kinds of Nerves in PNS

• Spinal Nerves: From spinal cord to different aprts of the body

  • 31 pairs

• Cranial Nerves: From your brain to parts of head and some internal organs

  • 12 pairs

PNS

• 2 General Functions:

  • Sensory: To the CNS

  • Motor Function: From the CNS

    • Accomplished by Motor Neurons

Motor Neurons

• Operate on two kinds of muscle

  • Skeletal Muscle

    • Controlled by somatic portion of the Peripheral Motor System

    • Somatic: Initiates activity

  • Visceral Muscle and Glands

    • Autonomic: Changing activity of muscle

Two “Modes”

• Autonomic Nervous System

  • Sympathetic: Excited, stimulated

  • Parasympathetic: Calm, tired

Spinal Cord

• 3 Functions:

  • Transmits information between the spinal nerves and the brain

  • Organize some simple rhythmic skeletal muscle activity

  • Organize some reflexes

    • Flexion Reflex: Reflex that causes you to withdraw one of your limbs after experiencing pain

Brainstem

• 3 Structures:

  • Medulla: Simple autonomic functions

  • Pons: Controls more complicated reflexes than the spine can handle (eg Posture Reflex)

  • Midbrain: Does simple survival skills (eg eating, drinking, attacking, sleeping)

Thalamus

• The relay station of the brain; all sensory information will go to the thalamus first, then to the rest of the brain

  • Almost every action you take goes through the thalamus

Cerebellum

Means “little brain,” responsible for fine motor movements and fast ballistic movements (pre-planned, executed without further guidance)

Basal Ganglia

Responsible for gross motor movements and integrating motor movements of a sequence

Complementary Function

Cerebellum + Basal Ganglia

Limbic System

• Means “border” (between evolutionary old vs. new)

  • Amygdala: Important for emotional function

  • Hippocampus: Important aspects of how our memory works

    • Helps us with the formation of memories

  • Hypothalamus: Controls the autonomic nervous system and contain drive states

    • Drive States: When there’s a thing you need, your behavior motivates you to get it

Cortex

• Means “ bark” (cortex is outside of the brain, because everything else is sub-cortical)

  • Aka “Neocortical”

• Wrinkly because it’s like a sheet (flat), evolution crumples up the brain so it fits in the skull

• Gyri: Bulges of Cortex

• Crevices of Cortex

  • Sulci: Small crevices

  • Fissures: Big crevices

Frontal Lobe

• Located in front

• Planning actions and changing strategies

Parietal Lobe

• Means “wall,” located top middle

• Spatial Perception, Somatosensation and some Language

Temporal Lobe

• Closest to brainstem

• Auditory Processing

Occipital Lobe

• Located in back of head

• Visual Processing

Functional Descriptions

• Input: Primary Sensory Areas

  • Receive signals from your sense organs through your thalamus

  • Primary Visual Cortex: Responsible for things you can see (near occipital lobe)

  • Primary Auditory Cortex: Responsible for things you hear (near temporal lobe)

  • Primary Somatosensory Cortex: Responsible for body senses (near parietal lobe)

Primary Motor Areas

• Last part of your cortex that sends information about some movement you want to make

  • Located in back of frontal lobe

Association Cortex

• Everything in between (facilitates association)

  • More association cortices, more intelligent/complex the organism is

Principles of Cortical Organization

• Principle of Topographic Organization: Things that are adjacent in the real world are represented in adjacent cortexes

• Tonotopic Organization: Notes that are adjacent in the scale are adjacent in the primary auditory cortex

Principle of Cortical Magnification

The more complex or sensitive an ability, the more cortex that’s used for it

Cortical Hemispheres

• Left and Right hemispheres for each lobe, separated by the midline fissure

  • Corpus Callosum: Connected to each other via this

Contralateral Organization

• “Other Side” Organization

  • Everything on the left side of the world is represented in the right side, and vice versa

Hemispheric Specialization

• The different things we do tend to collect in one hemisphere or another

  • Left Hemisphere: Ability to speak, language

  • Right Hemisphere: Spatial

Split-Brain Patients

• Patients who have a form of epilepsy can have their Corpus Callosum severed to stop uncontrolled electrical activity that causes seizures

  • Unilateral presentation: “One side” presentation

Action Potential

All or none electrical signal that travels down the axon of the neuron

Elements that Allow Signal to Happen

• Components:

  • Cell Membrane: Porous skin that allows some particles through

    • Channels: “Doors” that only allow certain particles through (Na+ and K+ Channels)

  • Surrounded by Extracellular Fluid, Intracellular Fluid inside cell

    • Extracellular Particles: Na+ (sodium ions) and Cl- (chloride ions)

    • Intracellular Particles: K+ (potassium ions) and protein molecules

  • Sodium Potassium Pump

  • 2 Kinds of Forces:

    • Electric Force: Like charges repel, opposite charges attract

    • Osmotic (Concentration) Force: Particles tend to distribute themselves (want equilibrium)

Resting State

• Particles distributed as follows:

  • K+ inside, Na+ outside

  • Na+ channels are closed

  • K+ channels slightly open so some K+ ions sneak out into extracellular fluid

  • At -70 mV

What Causes Na+ Channels to Open?

• Two things:

  • Neurotransmitters: Starts Action Potential

  • When inside of cell starts to become more positive

    • Causes action potential to move

    • Voltage-Dependent Channels

When Sodium Channels Open

• What Happens:

  • Na+ ions go inside

  • When inside of cells hit +30 mV

    • K+ channels open wide

    • Na+ channels close

Hyperpolarization

• K+ channels close

• Sodium-Potassium Pump moves Na+ out and K+ in

Sensation

• The simple experience associated with a physical stimulus

  • The process by which physical energy is converted into a brain signal

Perception

• Physiological, meaningless

  • Organization and meaningful interpretation of sensory information

  • Relatively psychological, meaningful

Chain of Sensation

• 3 Steps:

  • Physical Stimulus

  • Physiological Response

  • Sensory Experience

Vision

• Physical Stimulus: Visible Light

  • Visible Stimulus: EM radiation w/ wavelengths between 400 and 700 nm

Structures of the Eye

• Cornea: Thin, clear film that covers eye, protects eye and focuses light

• Pupil: Black hole in middle fo eye, lets light in

• Iris: Gives eye its color, muscle that changes the size of the pupil

• Lens: Additionally focuses light, muscles attached to it squishes the lens to change its thickness and adjust focus

  • Myopia (Near-sightedness): Lens is too curved

• Retina: Photosensitive layer of cells in the back of the eye

Transduction

Conversion of physical energy into a neural signal

Photoreceptors

• Light-sensitive neurons in the retina

  • Rods and Cones: Form synapses with other cells that do processing

  • Photochemical: Molecule that changes its geometry in response to light; increasing charge inside the cell

Retinal Ganglion Cells

• Have signals sent to them by photoreceptors

  • Axions of R.G. Cells form the optic nerve

  • Distributed across retina, come together to form optic nerve

  • Blind Spot: Where the optic nerve is

    • Located in different parts of visual field to make up for each other, also compensated for by the brains

  • Optic Disk: Part of reaction w/ no photoreceptors

Rods

• Responsible for helping you see in dim light (only 1 kind)

• Extremely light sensitive, too much light causes rods to be oversaturated

• Low Acuity: Can’t make out fine patterns

• Poor neural convergence

Cones

• Allow you to see color (3 kinds)

• Less sensitive to light, so you usually use them during the day

• High Acuity: Make out fine patterns, low neural convergence

Fovea

Middle of retina hit by light from things you are looking directly at

Periphery

Outside the fovea

Function of Color Vision

• Sense the surface property of objects

• Unidimensional physically

Psychological Nature of Color

• Even though it is unidimensional physically, it’s multidimensional psychologically

  • Additive color mixing

Three Primaries Law

Color sensed from any single wavelength can always be matched by mixing together three other wavelengths

The Trichromatic Theory of Color Vision

• 3 kinds of cones in our retina

  • Slightly different photochemicals in cones

  • Red Cones: Respond to long wavelengths

  • Blue Cones: Respond to short wavelengths

  • Green Cones: Respond to medium wavelengths

Opponent Nature of Color

• Every particular color you see has an opposite color

  • Yellow → Blue

  • Green → Red

  • Black → White

Law of Complementarity

Any color can be additively mixed with some other color so that the result is white

The Opponent Process Theory of Color Vision

• The way that you see color comes from two opponent color systems

  • Retinal ganglion cell activity

    • Collect signal and send it to brain, but strength of signal can cause the brain to interpret it as one color or another

Which Theory Works?

• Both! Cone system is wired to retinal ganglion cells

Form Perception

Recognition of visual objects

Template Theory of Form Perception (?)

• The way we recognize objects is by comparing a visual image to a stored memory of that visual image

  • Probably wrong because visual images of objects are too varied to be described by any simple set of templates

2 Kinds of Information

• Bottom-Up Information: Info perceived from the world

• Top-Down Information: Info that comes from an educated guess

  • Any time you see anything, you usually use a mix of both of these

Feature-Integration Theory

• Analysis of visual info occurs in 2 steps

  • Detection of Features: Detect simplest visual pieces of information

    • Happens automatically and in-parallel

  • Integration of Features: Put features together

    • Less automatic, more serial

Gestalt Principles

• Tells us how to group features of objects together based on what we know

  • 6 Principles

Proximity

Features that are close together tend to be perceived as part of the same object

Similarity

Features that are similar tend to be perceived as being part of the same object

Closure

We tend to extrapolate or extend features to bring them into closed holes

Good Continuation

Features tend to continue on a smooth path rather than change abruptly

Common Movement

Features that move together tend to be grouped together

Good Form

Features tend to get grouped together if they are symmetrical or organized

Principle of Maximum Likelihood

• Overarching principle

  • Organize a feature set in a way that is most likely given what you know about the world

Subjective Contour

• Perceived edge of surface when there is no edge

• Follows Principle of Maximum Likelihood

Recognition

• By Components Theory (tolerate variability)

• Multi-step process (eg recognizing words)

  • Detect a bunch of features

  • Group features into letters

  • Configuration of letters → Word