PPT

• Consciousness is a state of being awake and aware of one’ssurroundings, the awareness of perception of something by aperson, and the fact of awareness by the mind of itself andthe world.
• Many explain the result as a sort of neurological blip, somescientists believe that it is possible to discover the basis forthese experiences and perhaps even prove that there isindeed life after death, or at least some remnant of life thatdoesn’t expire along with the body.
• According to Hameroff, consciousness is based on smallstructures that are called microtubules and are found inside thebrain.
• That is, if consciousness is a quantum phenomenon, then it is constituted of the same substance that makes up the rest of the universe, which has existed since the beginning of time and is made up of the geometry of time itself. Quantum predicts very strange things about how matter works that are completely at odds with how things seem to work in the real world.
• Einstein saw quantum theory as means to describe nature. He thought that describing reality required firm predictions followed by direct observations.
• In order to understand what the brain does, it isfirst necessary to understand what it is—to knowthe names and locations of its major parts andhow they are connected to one another.
• our experiences depend on the activity of a hugenumber of separate but interconnected cells. Tounderstand the nervous system, the place to begin is toexamine the cells that compose it.
• The nervous system and theendocrine system control thefunctions of the body.
• Thenervous system is composedbasically of specialized cells,whose function is to receivesensory stimuli and totransmit them to effectororgans,whether muscular orglandular
• The sensory stimuli that arise either outside or inside the body are correlated within the nervous system, and the efferent impulses are coordinated so that the effector organs work harmoniously together for the well-being of the individual.
• The central nervous system (CNS) is the division of the nervous system located within the skull and spine.
• Peripheral nervous system (PNS) is the division located outside the skull and spine.
• The central nervous system is composed of two divisions: the brain and the spinal cord. The brain is the part of the CNS located in the skull;the spinal cord is the part located in the spine.
• Somatic - controls voluntary muscles and conveys sensory information TO the nervous system.
• Autonomic - controls involuntary muscles. Sympathetic: expands energy, fight or flight. Parasympathetic - conserves energy, rest and digest.
• The central nervous system is composed of large numbers of excitable nerve cells and their processes, called neurons, which are supported by specialized tissue called neuroglia. The long processes of a nerve cell are called axons or nerve fibers.
• CNS is the body’s processing centre. The brain controls most of the functions of the body, including awareness, movement, thinking, speech, and the 5 senses of seeing, hearing, feeling, tasting and smelling. Nerves also connect the spinal cord to the brainstem.
• In the peripheral nervous system, the cranial and spinal nerves, which consist of bundles of nerve fibers or axons, conduct information to and from the central nervous system.
• Although the nerves are surrounded by fibrous sheaths as they run to different parts of the body, they a relatively unprotected and are commonly damaged by trauma.
• PNS: Cranial, spinal, autonomic nerves.
• Somatic Nervous System - is the part of the PNS that interacts with the external environment. It is composed of afferent nerves that SENSORY signals from the skin, muscles, and joints to the CNS and efferent nerves that carry MOTOR signals from the CNS to the muscles and joints
• PNS: connects the cns to organs, limbs, skin. carries sensory and motor information to and from the nervous system. allows the brain and spinal cord to receive and send info. and regulates involuntary body functions like heartbeat and breathing.
• Autonomic Nervous System - is the part of the peripheralnervous system that regulates the body’s internal environment. The autonomic nervous system controls specific body processes, such as blood circulation, digestion, breathing, urination, heartbeat, etc. The autonomic nervous system is named so because it works autonomously, i.e., without a person’s conscious effort.
• The primary function of the autonomic nervous system is homeostasis. Apart from maintaining the body’s internal environment, it is also involved in controlling and maintaining body functions like: Digestion MetabolismUrinationDefecationBlood pressure Sexual response Body temperature Heartbeat Breathing rate Fluid balance
• The autonomic nervous system has two kinds of efferent nerves:sympathetic nerves and parasympathetic nerves.

  
  

  The sympathetic nerves are autonomic motor nerves that projectfrom the CNS in the lumbar (small of the back) and thoracic (chestarea) regions of the spinal cord.

  
  

  The parasympathetic nerves are those autonomic motor nerves that project from the brain and sacral (lower back) region of the spinal cord.
• Parasympathetic Autonomic Nervous System: It is located in between the spinal cord and the medulla. It primarily stimulates the body’s “rest and digest” and “feed and breed” responses. The parasympathetic nervous system inhibits the body from overworking and restores the body to a calm and composed state.
• Sympathetic Autonomic Nervous System: It is the part of the autonomic nervous system located near the thoracic and lumbar regions in the spinal cord. Its primary function is to stimulate the body’s fight-or-flight response. It does this by regulating the heart rate, rate of respiration, pupillary response and more
• Neurons are some of the longest-lived cells in the body. Cells in the cerebral cortex has the same life span as you currently have.
• Neurons vary in size, shape, and function.
• Neurons are irreplaceable. Most neurons are amitotic (cannot divide)
• Neurons have huge appetite. They need constant and abundant glucose and oxygen.
• Except for mammalian red blood cells, all animal cells have a nucleus, the structure that contains the chromosomes.
• A mitochondrion (plural: mitochondria) is the structure that performs metabolic activities, providing the energy that the cell uses for allactivities.
• Mitochondria have genes separate from those in the nucleus of a cell, and mitochondria differ from one another genetically. People with overactive mitochondria tend to burn their fuel rapidly andoverheat, even in a cool environment. People whose mitochondria are less active than normal are predisposed to depression and pains. Mutated mitochondrial genes are a possible cause ofautism.
• All neurons include a soma (cell body), and most also have dendrites, an axon, and presynaptic terminals except for tiniest.
• The single long tubular neurite that conducts impulses away from the cell body is called the axon. The dendrites and axons are often referred to as nerve fiber projects.
• A neuron with more than two processes extending from its cell body is classified as a multipolar neuron; most neurons are multipolar.
• neuron with one process extending from its cell body is classified as a unipolar neuron, and aneuron with two processes extending from its cell body is classified as a bipolar neuron
• Neurons with a short axon or no axon at all are called interneurons; their function is to integrate neural activity within a single brain structure, not to conduct signals from one structure to another.
• Metabolic center of neurons. Contains the following: Nucleus – contains chromosomes. Ribosomes – synthesize new protein molecules. Mitochondria – performs metabolic activities/energy provider. Contains genes separate from nucleus. Axon Hillock – connects soma to axon. Range of diameter: 0.005 to 0.1 mm