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Psych Brain 1B

Nervous System

  • 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

Endocrine System

  • 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


Types of Neural Messaging

  • 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

Sleep and Dreams

  • 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)