Psych Unit 1

Nature (genes)

All the genes and heredity factors that influence who we are, from our physical appearance to our personality characteristics

Nurture (Environment)

Refers to all the environmental variables that impact who we are

Biological Psychology

Tends to stress the importance of genetics and biological influences (nature)

Hereditary

Sum of all biological processes by which particular characteristics are transmitted from parents to their offspring

Genes “Little Instructions”

Segments of DNA molecules are the functional units of hereditary, make up the body’s blueprint

Epigenetics

Study of changes in gene expression(inactive vs active) due to non genetic causes

Evidence shows that our environment can alter how our genes are expressed

Sensitive Periods

A particularl time in life in which some behaviors or physical characteristics should be expressed

Monozygotic Twins “Identical”

Result from a single fertilized egg that splits into two, genetically identical

Dizygotic Twins “Faternal”

Develop from 2 zygotes, share 50% of their DNA

Heritability

The extent to which differences in the appearance of a trait across several people can be accounted for by differences in their genes

Natural Selection

Process by which organisms traits that are better for their environment are more likely to survive and reproduce

Nervous system

The body’s communication network

Consisting of

Complex system of nerves

Neurons

Specialized cells

Central Nervous System (CNS)

Consist of brain and spinal cord
-Coordinates the actions and interactions of the brain and spinal cord. 
-Body’s main control center

Peripheral Nervous System (PNS)

Consist of all the nerves outside of the brain and spinal cord.
-Acts as sensory communication network to and from the rest of the body.

Motor Pathway

Signals from brain to muscles/glands

Sensory Pathway

Signals from sensory receptors to the brain.

Somatic Nervous System

Division of the PNS for controlling voluntary movements and relaying sensory information from the body to the CNS.

Sensory Neurons “Afferent Neurons”

Carry information from the nerves to the CNS
(Sensory-Afferent)

Motor Neurons “Efferent Neurons”

Carry information from the brain and spinal cord to muscle fibers throughout the body
(Motor-Efferent)

Autonomic Nervous System

Regulates involuntary and unconscious actions with conscious control.
(Such as breathing, blood pumping, digestion, and heartbeat).

Sympathetic Nervous System (CB Fav)

Emergency Response system in stress or danger.
-If something alarms, enrages, or challenges you, “Fight, Flight, or Freeze”
-Accelerates heartbeat, raise blood pressure, and slows digestion.

Parasympathetic Nervous System

Functions to calm the person
-”Rest & Digest”

Neuron

Specialized cell in the nervous system that receives and sends a message with electrochemical signals.

Glial Cells

Cells that provide physical support for the neurons to grow on and around.
-90% of the brain is glial cells
-Get nutrients to the neurons and provide insulation

Dendrites “Antenna”

Part of the neuron; receives electrical messages from other cells

Soma “Life support”

Cell body of the neuron that’s responsible for maintaining the cell and keeps the neurons functional.

Axon “Talker”

Fiber that extends from cell body to terminal endings.
-Job is to carry out messages to other cells

Myelin Sheath 

Layer of fatty substance produced by glial cells; wraps around axons to protect the nerves fibers from damage. 
-Insulates sheath
-Speeds up the neural message

Axon Terminals

Tips at the end of the Axon, send signals to other neurons.
-Terminal Buttons/Synaptic Knobs

Synapse

Meeting point between neurons. At the end of the terminal button; is a gap known as the synapse

Synaptic Vesicles

Store various neurotransmitters (chemicals) that are released at the synapse

Synaptic Cleft or Gap

Less than a millionth of an inch wide

Receptor Sites

Receives signals.
-Receptor sites are the lock that the neurotransmitter molecules fit into

Hemispheres 

2 Hemispheres; the left controls the right side of the body and the right hemisphere controls the left side of the body
-Cross wired

Corpus Callosum

Bundle of nerve fibers that connect the two hemispheres.
-messages move from one side of the brain to the other
-Seizures

Left Hemisphere

Specializes in analysis, language, speech, handwriting, and calculation

Right Hemisphere

Specializes in processing, perception, visualization, and recognition of faces

Cerebral Cortex

“Grey Matter”
Outer layer of the brain, the tissue is folded on itself
-Distinctly human traits including higher thought, language, and human consciousness

Frontal Lobe

Areas in the cortex in the front and top of the brain
-Associated with reasoning, motor skills, recognition, and expressive language
-Executive function

Prefrontal Cortex

Planning complex cognitive behavior, personality expression, decision making and moderating social behavior. 

Motor Cortex

In frontal lobe
Receives information to carry out movements

Broca’s Area (CB Fav)

In frontal lobe
Overlaps with left frontal lobe
-Controls motor function involved with speech production

Parietal Lobe

Sensations: Touch, pressure, temperature, and pain
-Located on top; that contains center for processing

Somatosensory Cortex

In parietal lobe
Part of your brain that receives and processes sensory information from the entire body

Occipital Lobe

Section of the brain located at the rear and bottom of the cerebral hemisphere containing the visual centers of the brain

Visual Association Cortex

In occipital lobe
Recognizes lines, angles, 3-d, movements, and shapes.

Primary Visual Cortex

In occipital lobe
Allows us to see by connecting optic nerves

Temporal Lobe

Just behind the temple; next to the ears
-Contains neurons responsible for sense of hearing and meaningful speech.
(And recognition, especially faces)

Wernicke’s Area (CB Fav)

Located in temporal lobe on the left side of the brain.
-Responsible for comprehension of speech

Brainstem

Most primitive section
Base of the brain connected to the spinal cord

Medulla Oblongata “Medulla”

Part of the brain stem
Located at the top of the spinal cord
-Controls life sustaining functions
-Heart rate, breathing, & Blood pressure
- Contralateral control (Cross wired)

Pons

Part of the Brainstem
-Stimulating breathing & controlling sleep cycles
-Bridge between cerebral hemisphere and both medulla and cerebellum

Cerebellum “Little Brain”

Helps control posture, balance, and coordination of voluntary movements
-Allows different muscle groups in body to act together and produce fluid movements

The Reticular Formation

Network of nerves that carry messages between parts of the brain stem
-Regulates pain
-filters unnecessary stimuli

Thalamus

Processes and transmits sensory information
-Considered “relay station”
-ROUTER of the brain
-Pass information on to the cerebral cortex

Limbic System

Network of structures beneath the cerebral cortex
Coordinates emotions like fear and aggression, memory, and drives like hunger and thirst

Hypothalamus

Bodily Homeostasis
-Connects with many regions
-Controlling hunger, thirst, emotional, body temperature, and circadian rhythm
-Controls pituitary glands by secreting hormones

Hippocampus

Plays critical role in formation, organization, and structure of new memories as well as connecting certain sensations and emotions to these memories

Amygdala

“Fear Center”
Primarily involved in processing emotion and survival responses
-Influence aggression and fear
-Active during potentially threatening situations

Neuroscience

“Brain Researchers”
An interdisciplinary brain science which seems to understand how the brain works

Phineas Gage Case Study

Explosives detonated part of his brain
Brain infection; lost his left eye
Had seizures
Was almost like a different person due to surgery removing frontal lobe

Lesioning Studies

Research Method in which areas of the brain are removed or disabled in order to determine their specific function
Generally performed on lab rats

Prefrontal Lobotomy

Operation that removes or disconnects the prefrontal cortex to control behavior.

Hemispherectomy

Brain surgery that is predominately used to treat epilepsy: removal of the halves of the brain
Reduces likelihood of seizures.

Brain Scanning

Not used to treat disorders; rather they provide information about the structure of the brain or about the activity of the brain

Electroencephalograph (EEG)

Measurement of electrical signals of neurons on the surface of the brain by recording from electrodes placed on the skull.

Computer Tomography (CT or CAT)

2-D X-ray photos that creates a 3-D image of organ; used to identify a muscle, bone disorder, tumor, or blood clot.

Magnetic Resonance Imaging (MRI)

Brain-imaging using radio waves and magnetic fields to produce 3-D detailed images. 

fMRI

Measures brain activity by detecting change in response to neural activity (More oxygen = increase in activity area)

Neuroplasticity

Brain plasticity: The ability of the brain to rewrite or create new connections throughout developmental stages (Decreases with age). Generally allows for function of a damaged part of the brain to be assumed by a different part.

Split Brain (Corpus Colostomy) 

Another surgery to treat extreme epilepsy in which the 2 hemispheres of the brain are separated by cutting the corpus collosum
-Neuroscientist Roger Sperry and Michael Gazzaniga studied split Brain patients.

Multiple Sclerosis

Autoimmune disease resulting from the immune system damaging Myelin Sheaths protecting neurons in the Nervous System

Myasthenia Gravis

Disease in Immune System blocks or destroys receptor sites for Acetylcholine, decreasing nerve signals muscles receive.

Neurotransmitters

Chemical messenger that carries, boosts, and balances signals between neurons or nerve cells and other cells in the body (Chemical Keys)

Excitatory Neurotransmitters

They excite connecting neurons causing them to fire, more action potentials are triggered.

Inhibitory Neurotransmitters

Inhibits/Prevents the next neurons from firing. 

Acetylcholne (ACh)

“Movement and Memory”
Neurotransmitter involved in learning, memory, and muscle action
Surplus: Muscle Spams
Deficit: Dementia, Alzheimer’s, lack of muscle movement/control, and myastrenia Gravis
-Excitatory
-Related to parasympathetic

Serotonin

“Mood”
Connected to feeling of well-being, regulation of emotion, and hunger
Surplus: Hallucinations
Deficit: Depression, anxiety, and OCD
-Exhibitory
-Major part of many drugs

Dopamine

“Reward”
Pleasure Chemical, associated with reward, learning, attention, emotion, addiction, and motivation
Surplus: Schizophrenia
Deficit: Depression, Parkinsons, Memory problems, ADHD, and Anxiety
-Exhibitory
-Associated with addiction

Norepinephrine

“Fight or Flight”
Increases alertness, arousal, and response to danger.
Surplus: Anxiety
Deficit: Depression
-Excitatory
-Constricts Blood Vessels

GABA

“Calming”
Sleepiness, calm, stress, and slowing nervous system. Also related to motor control and vision
Surplus: Over-relaxation and sedation, reaction time.
Deficit: Anxiety, Insomina, and Seizures
-Inhbitory
-Sleepiness
-Decreases anxiety and alertness.

Glutamate

“Memory”
Thinking, long-term memory, and learning
Surplus: Overstimulate brain, cause mood swings, migraines, and seizures
Deficit: Mental exhaustion, and lack of concentration
-Excitatory
-Most common neurotransmitter

Endorphins

“Euphoria”
Relieves pain and stress, gives feeling of elevation and euphoria, especially after exercise
Surplus: Not enough warning about pain
Deficit: More pain felt
-Inhibitory
-Released during exercise

Substance P

Transmit pain signals from different parts of the body to spinal cord and brain to be perceived.
Surplus: Nausea, stress, less control of emotional behaviors
Deficit: Negative impact on learning and memory
-Excitatory

Resting Potential

Neuron at rest
Inside is more negative than the outside
Potassium ions mostly inside
Sodium ions mostly outside

Selectively Permeable Membrane

Allows for clear resting and action potentials by blocking certain ions or molecules from the cell, while allowing others in. (Promotes homeostasis).

Step 1: Charge begins

Membrane receives a signal from the dendrite messages, it may being to allow positive ions ((sodium) from outside the cell to come inside the axon

Step 2: Threshold

The minimum level of stimulation from positive ions needed to depolarize a neuron, leading ot action potential.

All or none principal

A neuron always fires at full strength, or not at all. The speed and action potential is always the same.

Step 3: Depolarization

Process of sodium ions rushing into the neuron, which makes the inside more positive than it was at rest, triggering the action potential. 

Step 4: Action Potential

The neuron passes the information down the axon repeatedly until its made its way through. The chemicals will then cross the synaptic gap and stimulate the next neurons dendrites and the signal continues.

Step 5: Reuptake

After the neurotransmitters stimulate the receptors on the receiving neuron, the chemicals are taken back up into the sending neuron to be used again.

Step 6: Refractory Period

A period of inactivity after a neuron has fired where positive ions used for electrical charge are flushed away.