Our neurons communicating via neurotransmitters make up or body's nervous system
Our speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral nervous system and central nervous system
Peripheral nervous system (PNS)- the sensory and motor neurons that connect the central nervous system to the rest of the body
Two unique components
Somatic nervous system- voluntary control of our skeletal muscles
Heavily involved with our sensory neurons and motor neurons
Autonomic nervous system- controls our glands and our internal organ muscles- self regulating
Sympathetic nervous system-
Division of the autonomic nervous system that arouses the body, mobilizes its energy
Can alarm or challenge us-elevate our heart rate, slow digestion, raise blood pressure and sugar,- make us ready for action
Parasympathetic nervous system-
Division of the autonomic system that calms the body, conserving its energy
Produces opposite effects of the sympathetic so that our body returns to homeostasis
Central nervous system (CNS)- the brain and spinal cord
Brain- thinking , feeling, and acting; our humanity- tens of billions of neurons
Anatomical structure that resides in ou skull that performs numerous physiological functions and contains our mind the root of many psychological phenomena
Weighs approximately 3 lbs
There are multiple “levels” of your brain with varying complexity with different parts that each perform different functions
Cerebral Cortex- outermost layer of the brain- what we see when we look at a brain
Contains 20 billion nerve cells and 300 trillion synaptic connections
Divided into 2 halves called hemispheres
The left hemisphere controls the right side of the body and the right hemisphere controls the left side of the body
We divide each hemisphere up into smaller sections called lobes that are separated by fissures (folds)
Frontal lobe
Front of cerebral cortex (behind forehead)
Involved in speaking, muscle movement, planning, problem solving, critical thinking, and judgements
Contains motor cortex- located at the rear end of the frontal lobe and controls voluntary movements
Prefrontal cortex- recall and remember events from the past
Frontal association area- mostly deals with personality and forming thoughts and ideas
Parietal lobe
Middle of cerebral cortex, behind front lobe
Contains the somatosensory cortex- controls all sensational feeling in the body (works hand in hand with the frontal lobe’s motor strip)
Occipital lobe
Back of the brain
Processes and makes sense of the things we see
Creates images or visuals that we can understand- even when it is a topic we do not know (heffalump)
Temporal lobe
Side of our head, where the temple is
Hearing and spoken language
A special part of the temporal lobe is used to create sentences- coherent
Talking to yourself in your head
Brain Stem- heart of the brain that connects spinal cord and brain
Pons- upper part, movement and controlling sleep (works with motor cortex)
Medulla- lower part, breathing and heartbeat SOMETHING ANOU SLEPP?
Left hemisphere
The Old Brain
Thalamus- atop brain stem; sensory control center
Information comes in and out of the brain through the thalamus
Cerebellum- latin for “little brain”
Hang off brain stem- responsible for involuntary functions
Process sensory input enables non verbal learning and memory
movement and balance
Reticular formation
Reticula means “netlike”
Neuron network extending form the spinal cord up though the thalamus
Allows for multitasking by relaying sensory stimuli to other parts of the brain (helps thalamus)
Arousal and alertness
Limbic System
Lower brain system perform most of their functions involuntary but the limbic system is slightly more voluntary
Sits between the old brain structures and newer brain structures
Consists of the amygdala, hypothalamus, and the hippocampus
Amygdala- size of lima bean
Fear, anger, anxiety, and stress (not the only factor though/part of the brain)
Hypothalamus- bodily functions and maintenance
Hunger, thirst, body temperature, sexual behavior
Control pituitary gland- makes things happen by sending messages to other parts of the body and glands
Aims for homeostasis (not always thirsty or always hungry)
Hippocampus- memory
Processes our conscious and explicit memories
Hippocampus shrinks with age decreasing its function and making it hard to remember things, especially new things
Can be damaged in brain injuries like concussions
Spinal cord- two way informations highway connecting our peripheral with our brain
Reflexes- simple, automatic response to a sensory stimulus
The body's “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream (secondary)
Hormones- chemical messengers that are manufactured by glands in out endocrine system, travel through our body, and affect other tissues
Influence a wide array of areas- food, aggression, sex
Thyroid- affects our metabolism (life sustaining processes such as food conversion into energy)
Parathyroid- helps regulate the level of calcium in our blood
Pancreas- regulates the level of sugar in our blood
Pineal gland- releases melatonin- involved in sleep cycles
Ovaries- secretes female sex hormones- involved in reproduction
Testes- secretes male sex hormones- involved in reproduction
Our endocrine system works hand in hand with the nervous system to make sure all of the messages travel throughout our body
Hormones travel at a much slower rate than messages along neurons
Variety of glands perform various functions that affect our body
Adrenal Glands
Sit above our kidneys and release hormones that help arouse the body in times of stress
Increase heart rate, blood pressure, and blood sugar with surge of energy or give us a fight-or-flight response
The feeling the hormones provide will last after the sensation has passed
Pituitary Gland
Pea-sized gland located in the brain off of our hypothalamus (controlled by this)
Known as the master gland- releases a variety of hormones and helps control other glands
Human Growth Hormone- involved in our physical development
Oxytocin- involved in reproduction and sexual arousal; supports bonding, group cohesion, and trust
Our mental activity is constantly emitting electrical, metabolic, and magnetics signals that allow observation of our brain to work
Electroencephalogram (EEG)- an amplified recording of the waves of electrical activity sweeping across the brain's surface. These waves are measured by electrodes placed on the scalp; can also be used to evaluate nerve movement
Magnetoencephalography (MEG)- a brain imaging technique that measures magnetic fields from the brain’s natural electric activity
Computed Tomography Scan (CT Scan)- a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain’s structure
Positron Emission Tomography (PET Scan)- a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given ask
Magnetic Resonance Imaging (MRI)- a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRIs show brain anatomy
Functional MRI (fMRI)- a technique for revealing blood flow and therefore brain activity by comparing successive MRI scans. fMRI scans show brain function as well as structure
Misconceptions about sleep
When people dream of performing some activity, their limbs move in concert with the dream
Older adults sleep more than younger adults
Sleepwalkers act out their dreams
Some people dream every night and some rarely
Experts recommend insomnia be treated with occasional sleeping pills
Sleep- periodic natural loss of consciousness- distinct from unconsciousness resulting from coma, general anesthesia, or hibernation
Our bodies function on a 24 hour cycle of the day because of our internal biological clock called circadian rhythm
Tied to wakefulness and body temperature
Teenagers and young adults- more energized in the evening, “night owls”
As you get older we transition to morning-loving “traits”
Morning types typically tend to do better in school, take more initiative, be more punctual, and be less vulnerable to depression
Every 90 minutes we are asleep we cycle through distinct stages
REM Sleep- rapid eye movement sleep; a recurring sleep stage during which vivid dreams commonly occur, our muscles relax while bod systems are still activated
Alpha waves- relatively slow brain waves of a relaxed, awake state- show up as we begin to fall asleep
As we become comfortable in our surroundings, we will transition to NREM Sleep- non-REM sleep which encompasses all sleep stages except REM Sleep (slower breathing and irregular brain waves)
NREM-1- may cause hypnagogic sensations- bizarre experiences, such as jerking or a feeling of falling or floating weightlessly
NREM-2- can contain bursts of rapid, rhythmic brain wave activity called sleep spindles (20 mins)
NREM-3- 30 minutes with delta waves- large slow brain waves associated with deep sleep
We then transition back into NREM-2 before entering REM sleep- which will increase in length as the night goes on
Why do we sleep? Protection, recuperates, resort and rebuild our fading memories of the days experiences, creative thinking, growth
15 yes or no questions about whether or not you get enough sleep
Sleep Deprivation and Disorders
Effects of not getting enough sleep
Decreased
Ability to focus
Ability to store memories
Metabolic rate
Production of immune cells
Muscle strength
Reaction times
Increased
Risk of depression
Production of fat cells
Inflammation and arthritis
Risk of high blood pressure
Disorders
Insomnia- recurring problems in falling or staying asleep
Narcolepsy- a sleep disorder characterized by uncontrollable sleep attacks where the sufferer may lapse directly into REM sleep, often at inappropriate times
Sleep apnea- characterized by temporary cessation of breathing during sleep and repeated momentary awakenings
Sleepwalking and sleeptalking- doing normal walking activities while asleep; sleep talking can happen at any stage while sleepwalking is NREM-3
Night terrors- characterized by high arousal and an appearance of being terrified and seldom remembered (unlike nightmares)