Module 4: Incredible Nervous System AF

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Module 4 Incredible Nervous System A-F

• By Sergio Romero
• Period 1

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A. Genes Evolution

• Genetic instruction
• Evolution of the human brain

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Genetic Instruction

• Your brain and body develop according to complex
  chemical instructions that were written in a
  human cell no larger than a grain of sand
• 1. Fertilization human life begins when a
  fathers sperm penetrates a mothers egg.
• 2. Zygote is the cell that results when an egg
  is fertilized. A zygote contains 46 chromosomes
  arranged in 23 pairs. Its the largest human cell
  and contains the equivalent to 300,000 pages of
  typed-written instructions.
• 3. Chromosomes is a short, rodlike, microscopic
  structure that contains tightly coiled strands of
  chemical DNA.
• 4. Chemical alphabet The chemical alphabet is
  used to write instructions for the development
  and assembly of the 100 trillion highly
  specialized cells that make up the brain and
  body.
• 5. Genes and proteins Genes determine physical
  traits (eye color, shapes of ear lobes) as well
  as contribute to the development of emotional,
  cognitive, and behavioral traits. Proteins are
  chemical building blocks from which all the parts
  the brain and body are constructed.
• 6. Genome the human genome project mapped all
  the human genes.
• 7. An error in instruction Fragile X syndrome,
  an inherited developmental disability, is due to
  the defect in the X chromosome. It can result in
  physical changes, such as a relatively large head
  with protruding ears.

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Evolution Of the Human Brain

• Theory of evolution says that different species
  arose from a common ancestor and that those
  species that survived were the best adapted to
  meet the demands of the environment.
• According to the theory of evolution, present-day
  humans descended from a creature that split off
  from apes millions of years ago

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B. Studying The Living Brain

• Brain Scans
• Brain Scans MRI FMRI
• Brain Scans and Cognitive Neuroscience
• Tools Versus Animals

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Brain Scans

• In the past 10 years researchers have developed
  several brain scanning techniques that can look
  through the thick skull and picture the brain
  with astonishing clarity yet cause no damage to
  the extremely delicate brain cells.
• By using these techniques, researchers are
  mapping a variety of cognitive functions as well
  as sites of emotional feelings and hunger
  sensations.

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Brain Scans MRI FMRI

• MRI or magnetic resonance imaging, involves
  passing nonharmful radio frequencies through the
  brain. A computer measures how theses signals
  interact with brain cells and transforms this
  interaction into an incredibly detailed image of
  the brain (or body). MRIs are used to study the
  structures of the brain.
• The f in FMRI (functional magnetic resonance
  imaging) stands for the functional and measures
  the activity of specific neurons that are
  functioning during cognitive tasks, such as
  thinking, listening, or reading.

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Brain Scans and Cognitive Neuroscience

• Cognitive neuroscience involves using imaging
  techniques to literally light up your thoughts
  and feelings.
• PET scans involves injecting a slightly
  radioactive solution into the blood and then
  measuring the amount of radiation absorbed by
  brain cells called neurons. Different levels of
  absorption are represented by colors- red and
  yellow indicate maximum activity of neurons,
  while blue and green indicate minimal activity.

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Tools Versus Animals

• Thinking of animals occurs in the back of the
  brain.
• Thinking of tools occurs in the front of the
  brain.
• Researchers concluded that you are able to
  identify thousands of objects, in large part,
  because the brain has two separate built-in
  systems one for thoughts about naming animals,
  which involves distinguishing between size,
  shapes, and colors, and another for thoughts
  about naming tools, which involves thinking about
  how tools are used.

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C. Organization of the Brain

• Divisions of the Nervous System
• Major Parts of the Brain

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Divisions of the Nervous System

• Major divisions of the nervous system are
• The central nervous system-CNS is made up of the
  brain and spinal cord.
• You are capable of many complex cognitive
  functions-such as thinking, speaking, and
  reading, as well as moving, feeling, seeing, and
  hearing-because of your central nervous system.
• The peripheral nervous system-PNS includes all
  the nerves that extend from the spinal cord and
  carry messages to and from various muscles,
  glands, and sense organs located throughout the
  body.
• The PNS has two subdivisions, the somatic and
  autonomic nervous system.
• Somatic nervous system consists of a network or
  nerves that connect either to sensory receptors
  or to muscles that you can move voluntarily.
• ANS-Autonomic nervous system regulates heart
  rate, breathing, blood pressure, digestion,
  hormone secretion, and other functions. The ANS
  usually functions without conscious effort, which
  means that only a few of its responses, such as
  breathing, can be controlled voluntarily.
• The ANS also has two subdivisions, the
  sympathetic division and parasympathetic
  division.
• Sympathetic division is triggered by threatening
  or challenging physical or psychological stimuli,
  increases physiological arousal and prepares the
  body for action.
• Parasympathetic division returns the body to a
  calmer, relaxed state and is involved in
  digestion.

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Major Parts of the Brain

• Midbrain has a reward or pleasure center, which
  is stimulated by food, sex, money, music, looking
  at attractive faces, and some drugs (cocaine)
  has areas for visual auditory reflexes, such as
  automatically turning your head toward a noise.
• Hindbrain has three distinct structures the
  pons, medulla, and cerebellum. It is also a
  primitive part of the brain.
• Pons functions as a bridge to interconnect
  messages between the spinal cord and brain. The
  pons also makes chemicals involved in sleep.
• Medulla which is located at the top of the
  spinal cord, includes a group of cells that
  control vital reflexes, such as respiration,
  heart rate, and blood pressure.
• Cerebellum which is located at the very back and
  underneath the brain, is involved in coordinating
  motor movements but not in initiating voluntary
  movements.
• Forebrain which is the largest part of the
  brain, has right and left sides that are called
  hemispheres. The hemispheres, which are connected
  to a wide band of fibers, are responsible for
  learning and memory, speaking and language, etc.

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D. Control Centers Four Lobes

• Overall View of the Cortex
• Frontal Lobe Functions
• Parietal Lobe Functions
• Temporal Lobe Functions
• Occipital Lobe Functions

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Overall View of the Cortex

• The cortex is the thin layer of cells that
  essentially covers the entire surface or the
  forebrain. The vast majority of our neurons are
  located in the cortex, which folds over on itself
  so that it forms a large surface area.
• The cortex is divided into four separate areas,
  or lobes, each with different functions.
• The frontal lobe is involved with personality,
  emotions, and motor behaviors.
• The parietal lobe is involved with perception
  and sensory experiences.
• The occipital lobe is involved with processing
  visual information.
• The temporal lobe is involved with hearing and
  speaking.

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Frontal Lobe Functions

• The frontal lobe, which is located in the front
  part of the brain, includes a huge area of the
  cortex.
• The frontal lobe is involved in many functions
  performing voluntary motor movements,
  interpreting and performing emotional behaviors,
  behaving normally in social situations,
  maintaining a healthy personality, paying
  attention to things in the environment, making
  decisions, and executing plans.
• Because the frontal lobe is involved in making
  decisions, planning, reasoning, and carrying out
  behaviors, it is said to have executive
  functions.

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Parietal Lobe Functions

• The parietal lobe is located directly behind the
  frontal lobe.
• The parietal lobes functions include processing
  sensory information from body parts, which
  include touching, locating positions of limbs,
  and feeling temperature and pain, and carrying
  out several cognitive functions, such as
  attending to and perceiving objects.

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Temporal Lobe Functions

• The temporal lobe is located directly below the
  parietal lobe and is involved in hearing,
  speaking coherently, and understanding verbal and
  written material.
• The primary auditory cortex, which is located on
  the top edge of each temporal lobe, receives
  electrical signals from receptors in the ear and
  transforms these signals into meaningless sound
  sensations, such as vowels and consonants.
• The auditory association area transforms basic
  information, such as noises or sounds, into
  recognizable auditory information, such as words
  or music.
• Wernickes, which is located in the left temporal
  lobe, is necessary for speaking in coherent
  sentences and for understanding speech.

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Occipital Lobe Functions

• The occipital lobe is located at the very back of
  the brain and is involved in processing visual
  information, which includes seeing colors and
  perceiving and recognizing objects, animals, and
  people.
• The primary visual cortex receives electrical
  signals from receptors in the eyes and transforms
  these signals into meaningless basic visual
  sensations, such as lights, lines, shadows,
  colors, and textures.
• The visual association area transforms basic
  sensations, such as lights, lines, colors, and
  textures, into complete, meaningful visual
  perceptions, such as persons, objects, or animals.

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E. Limbic System Old Brain

• Structures and Functions
• Autonomic Nervous System

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Structures and Functions

• The limbic system refers to a group of about half
  a dozen interconnected structures that make up
  the core of the forebrain.
• The limbic systems structures are involved with
  regulating many motivational behaviors such as,
  obtaining food, drink, and sex with organizing
  emotional behaviors such as fear, anger, and
  aggression and with storing memories.
• Important parts of the limbic system
• Hypothalamus regulates many motivational
  behaviors, including eating, drinking, sexual
  responses emotional behaviors, such as arousing
  the body when fighting or fleeing and the
  secretion of hormones, such as occurs at puberty.
• Amygdala receives input from all the senses.
• Thalamus is involved in receiving sensory
  information, doing some initial processing, and
  then relaying the sensory information to areas of
  the cortex.
• Hippocampus is involved in saving many kinds of
  fleeting memories by putting them into permanent
  storage in various parts of the brain.

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Autonomic Nervous System

• The sympathetic division, which is one part of
  the ANS, is triggered by threatening or
  challenging physical stimuli, such as a snake, or
  by psychological stimuli, such as the thought of
  having to give a public speech. Once triggered,
  the sympathetic division increases the bodys
  physiological arousal.
• The fight-or-flight response, which is a state of
  increased physiological arousal caused by
  activation of the sympathetic division, helps the
  body cope with and survive threatening
  situations.
• The parasympathetic division, which is the other
  part of the ANS, decreases physiological arousal
  and helps return the body to a calmer, more
  relaxed state. It also stimulates digestion
  during eating.

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F. Endocrine System

• Definition
• Control Center
• Other Glands

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Definition

• The endocrine system is made up of numerous
  glands that are located throughout the body.
• These glands secrete various chemicals, called
  hormones, which affect organs, muscles, and other
  glands in the body.

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Control Center

• In many ways, the hypothalamus, which Is located
  in the lower middle part of the brain, controls
  much of the endocrine system by regulating the
  pituitary gland, which is located directly below
  and outside the brain.
• The hypothalamus is often called the control
  center of the endocrine system

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Other Glands

• Pituitary gland a key component of the endocrine
  system, it is divided into anterior and posterior
  sections.
• Posterior pituitary the rear portion of the
  pituitary regulates water and salt balance.
• Anterior pituitary the front part of the
  pituitary regulates growth through secretion of
  growth hormones and produces hormones that
  control the adrenal cortex, pancreas, thyroids,
  and gonads.
• Pancreas this organ regulates the level of sugar
  in the bloodstream by secreting insulin
• Thyroid this gland, which is located in the
  neck. Regulates metabolism through secretion of
  hormones.
• Adrenal glands the adrenal cortex secretes
  hormones that regulate sugar and salt balances
  and helps the body resist stress they are also
  responsible for growth of pubic hairs. The
  adrenal medulla secretes two hormones that arouse
  the body to deal with stress and emergencies.
• Gonads in females, the ovaries produce hormones
  that regulate sexual development, ovulation, and
  growth of sex organs. In males, the testes
  produce hormones that regulate sexual
  development, production of sperm, and growth of
  sex organs.