Psychology Unit 1

Identical twins

monozygotic - one egg/ genetically identical

Fraternal twins

dizygotic - two eggs/ genetically no more similar than ordinary siblings

Central Nervous System (CNS)

brain and spinal cord in the center of the body, dictates

Peripheral Nervous System(PNS)

Responsible for gathering information and for transmitting CNS decisions to other body parts: PNS does

two parts: Somatic nervous system and Autonomic nervous system

Somatic nervous system

voluntary actions/control of skeletal muscles

Autonomic nervous system

automatic actions like breathing, heart beat, digestion, glandular activity

Sympathetic nervous system

arouses and expends energy: accelerate heartbeat - for flight, fight, freeze

Parasympathetic nervous system

calms the body down after the danger/stress/triggering event had passed

Information travels through the nervous system via:

sensory neurons, motor neurons, and interneurons

Sensory neurons:

carry messages from the body’s tissues and sensory receptors inward (afferent) to brain and spinal cord for processing

Motor neurons:

carry instructions form CNS to muscles and glands: so outward (efferent)

Interneurons:

between sensory input and motor output in brain and spinal cord

Receptor sites:

where the incoming neurotransmitters land - located at the tip of dendrites

Dendrites:

tree like branches coming out of the soma, pass info onto the soma

Soma:

nucleus - body: its the command center and will decide what to do with the info given to it by the dendrites

Axon:

single lengthy fiber that passes messages from the soma to other neurons, glands, muscles A→B

Myelin Sheath:

(some axons are encased in this) a layer of fatty tissue that insulates the axon and speeds their impulses, ex: ever cut open a wire? Copper is the axon, protective covering is the myelin sheath

Multiple sclerosis:

(if the Myelin Sheath degenerates) communication to muscles slows with eventual loss of muscle control

Glial cells:

support the nerve cells; they are the worker bees who provide nutrients, guide neural connections, mop up ions and neurotransmitters

At the end of the axon are terminal buttons or axon terminals

these are small knobs that will release neurotransmitters, and these neurotransmitters send the message to the next neuron, muscle, gland, or whatever

The neuron is said to be in Resting potential just hanging around waiting for the ball to drop

When hanging out, waiting for information

The ball has dropped, a message has been sent - a threshold has been reached:

the minimum level of simulation needed to trigger a neural impulse

As soon as the threshold is reached, the all-or-none response/ all-or-nothing principle

the reaction to the message is either let’s fire or let’s not

The neural impulse is called an action potential

a brief electrical charge that travels down the axon

Direction of impulse

The action only goes in one direction - down the neuron, and when the charge reaches the axon terminals, neurotransmitters are released to send the message to the next neuron - the ball is dropped

Refractory Period

Once the ball is dropped, the neuron needs to reset

Depolarization

the electrical charge down the axon

Repolarization

in the refractory period, all the negative and positive sodium ions need to reset

Reuptake

Once the message has been received, the neurotransmitter drops away, returns to its original neuron

Agonists

increase the neurotransmitters actions

Antagonists

occupy the receptor site and prevent the real neurotransmitters from working

The endocrine system

we also have a way we send information a little slower

Adrenal glands

adrenal glands secrete adrenaline and noradrenaline for fight-flight-or-freeze response

Pituitary gland

which is the gland that controls all the other glands and is responsible for our physical growth

Endocrine hangover

Hormones take longer to deliver the message , but their effects last longer

Psychoactive drugs

chemicals that alter the brain, causing changes in the perceptions and/or moods

Depressants

Drugs that calm neural activity and slow body functions

Barbiturates

tranquilizers, they depress the nervous system and are usually prescribed to induce sleep or reduce anxiety

Opioids

derived from opium are in the medical world are used to reduce pain. Often called narcotics

Stimulants

drugs that excite neural activity and speed up body functions

Hallucinogens

Distort perceptions and evoke sensory images in the absence of sensory input (which is why these drugs are called psychedelics, meaning “mind-manifesting”

Localization of function

which parts of the brain do what

EEG

electroencephalogram is an amplified readout of your brain waves

MEG

magnetoencephalography - measures magnetic fields from the brain’s natural electrical activity

CT

(computed tomography) scan examines the brain by taking X-ray photographs that can reveal brain damage

PET

(Positron Emission Tomography) scans detect brain activity by tracking sugar glucose usage

MRI

(magnetic resonance imaging) a technique that uses magnetic fields to produce computer - generated images of soft tissues in high definition

fMRI

(functional magnetic resonance imaging) starts like a regular MRI process, but also monitors blood flow and oxygen consumption throughout the brain to identify areas of high activity during particular tasks

The Brainstem

begins where the spinal cord swells as it enters the skull, controls our automatic survival functions

Medulla

Apart of the brainstem, it is kind of the base of the brainstem and it controls heartbeat and breathing

The pons

sits just above the medulla, and it helps coordinates movement and control sleep

Cerebellum

extending from the rear of the brainstorm are two little spheres, often called “the little brain” motor movement coordination and nonverbal and procedural learning take place

The reticular formation

begins in the hindbrain and travels through the mid- and forebrain! It filters information and plays an important role in controlling arousal

Limbic system

key to emotions, motivations, and memory

Amygdala

aggression, rage, and fear

Hypothalamus

hunger, thirst, body temp, maintaining, homeostasis (steady internal state)

hippocampus

explicit (conscious) memories - facts and events - for storage

Thalamus

sensory control center (but not smell) - receives all sensory information and then routes it to the appropriate parts of the cerebrum (for interpretation), the cerebellum and the medulla (for what to do)

cerebrum

divided into two halves, each half has four lobes (frontal, parietal, temporal. and occipital)

Frontal

linguistic processing, muscle movements, higher-order thinking, executive functioning (making plans, using judgement) and personality has the motor cortex

Parietal

receives sensory input, touch and body position; has the somatosensory cortex

Occipital

receives visual information; has the visual cortex

Temporal

auditory information, language processing; has the auditory cortex

Association areas

they are not about motor or sensory functions, but higher mental functions such as learning, remembering, thinking, and speaking

Broca’s area

controls our ability to speak - but curiously not our ability to sing

Wernicke’s area

controls our ability to understand/comprehend language

Plasticity or neuroplasticity

the brain’s ability to change - especially during childhood - simply said: the ability to rewire itself

Neurogenesis

producing new neurons

The corpus callosum

a large band of neural fibers that connect the hemispheres and carry messages between them

Sleep

a periodic, natural loss of consciousness - as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation

Circadian rhythm

Our 24 hour biological clock, our 90 minute sleep cycle

Alpha waves

Relatively slow brain waves

Hypnagogic sensations

During NREM 1 you may experience hallucinations; you may have the sensation of falling, floating, jerking around

Sleep spindles and NREM 2

burst of rapid, rhythmic brain-wave activity

relax more deeply, 20 minutes

NREM 3 and Delta waves

transition to the deep sleep

slow waves and difficult to wake up

REM

(rapid eye movement) sleep, for about 10 minutes, your brain waves are rapid and your breathing and heart rate will accelerate

Sleep paralysis or paradoxical sleep

Your motor cortex is active, but the brainstem blocks the messages for your body to move; your brain is super active but your muscles are deeply relaxed

Suprachiasmatic nucleus (SCN)

Bright light tweaks the circadian rhythm by activating light-sensitive retinal proteins; these proteins send signals to it

Melatonin

the neurotransmitter that tells us to go to sleep, and the disruption to the circadian rhythm cause desynchronization/social jet lag

Ghrelin

hunger-arousing hormone

Leptin

hunger-suppressing hormone

cortisol

stress hormone

Insomnia

What is it? You cant fall asleep and/or you can’t stay asleep

who gets it? Older adults, more women than men

What are its effects? Chronic tiredness; reliance on sleeping pills and alcohol which reduce REM sleep and lead to tolerance - a state in which increasing doses are needed to produce the desired effect

Common treatment? Drugs; Cognitive Behavior Therapy (CBT)

Narcolepsy

What is it? Sudden attacks of overwhelming sleepiness usually at moments of emotional times

Who gets it? Ages 10-30, more so children

What are its effects? Risk of falling asleep at a dangerous moment; everyday activities like driving require extra caution

Common treatment: medication

REM Sleep Behavior Disorder

What is it? A disorder in which the normal paralysis that occurs during REM does NOT happen

Who gets it? Men over the age of 50

What are its effects? Risk of accidental injury to the sleeper or to a bed partner because of twitching, kicking, punching, acting out one’s dreams

Common treatment: Medication/melatonin

Sleep Apnea

What is it? Breathing stops repeatedly while sleeping

Who gets it? Middle-aged, obese men

What are its effects? Fatigue; depression (as a result of slow-wave sleep deprivation)

Most common treatment? CPAP, surgery, quit smoking, limit alcohol, sleep on your side, not your back

Sleepwalking

What is it? Doing normal waking activities (sitting up, walking, speaking) while asleep; sleepwalking occurs during NREM-3 sleep; sleep talking can occur during any sleep stage

who gets it? sleepwalking: mostly children 4-8 years old

What are its effects? None really as most sleepwalkers return to bed on their own or guided by a family member

Common treatment - nothing really

Latent content

What the dream is really about (wish fulfillment theory)

Manifest content

the plot of the dream

The information processing theory

HS student with high grades sleep 25 min more per night than students with low grades

The physiological function theory

infants, whose neural networks are fast developing, spend much of their abundant sleep time in REM sleep

Activation-synthesis theory

the brain is never off, and it still has tons of data to sift through, and your brain waves indicate you are awake but you’re not, so the brain makes up a story to try and make sense of the crazy signals, the neural static, running through it

Cognitive development theory

No matter the age, dreams draw on our understanding, concepts, schemes, knowledge

REM rebound

going into REM sleep following deprivation

Prosopagnosia

face blindness, something in the right hemisphere is not working

Top-down processing

starts with your experiences and expectations and then looks at details

Bottom-up processing

looks at the details then matches it to your experiences and expectations

Signal Detection Theory

blends thresholds with motivation and expectations; if you are anticipating something, listening for something, your senses are piqued

Subliminal

meaning, below one’s absolute threshold for conscious awareness

Sensory adaptation

we have diminished sensitivity as a consequence of constant simulation