NCM 116 (1-4)

• Definition of Perception:

  • The process of receiving stimuli or data and consciously organizing and translating them into meaningful information
• Definition of Coordination:

  • The combination of body activities that result in intended actions
• Special Senses involved in perception and coordination:

  • Vision (the eye)
  • Hearing and balance (the ear, which includes the auditory system and vestibular system)
  • Smell (the nose)
  • Taste (the tongue)
• Vision:

  • Physical information from the world (light) including hue, saturation, and brightness
  • Specialized sense organ (eye)
  • Specialized neural tissue (retina)
  • Specialized sensory receptors (rods, cones)
  • Sensory transduction: light - neural activity
• Parts of the Eye:

  • Upper eyelid: responsible for cosmetic appearance
  • Lower eyelid: collects and prevents preocular film and tears from overflowing
  • Pupil: allows light into the eye
  • Iris: regulates the amount of light that enters the eye
  • Eyebrow: helps direct moisture away from eyes, reduces light entry, and keeps dirt away
  • Lateral angle of eye: the lateral end of the palpebral fissure
• Lacrimal Gland:

  • Tear glands that release fluid to cleanse and protect the eye's surface
  • Lacrimal ducts: transmit tears from the eye surface to the nasal cavity
  • Lacrimal canaliculi: small channels in each eyelid that drain lacrimal fluid
  • Lacrimal sac: collects tears that drain out of the eyes
  • Nasolacrimal duct: opens at the inferior meatus located underneath the inferior nasal turbinate
• The Iris:

  • Circular smooth muscles that constrict the pupillary aperture
  • Radial smooth muscles that dilate the pupil
• The Lens:

  • Ciliary body (ciliary muscle): controls accommodation for viewing objects at varying distances
  • Suspensory ligaments: crucial for keeping the eyeball in its usual posture within the orbit
• Rods and Cones:

  • Cone cell: responsible for color vision
  • Rod cell: perceives size, shape, and brightness of visual images
  • Horizontal cell: increases contrast via lateral inhibition
  • Bipolar cells: provide main pathways from photoreceptors to ganglion cells
  • Amacrine cells: major carriers of rod signals to ganglion cells
  • Interplexiform cell: regulates lateral inhibitory effects in the retina
  • Ganglion cell: projection neurons conveying information from retinal neurons to the brain
• Basic Parts of the Neuron:

  • Cell body (soma): contains genetic information and provides energy
  • Axon: transmits electric signals between brain cells
  • Dendrite: branch extensions that receive stimuli from other neurons
• Types of Neurons:

  • Multipolar neurons: receive impulses from multiple neurons
  • Bipolar neurons: send signals and receive information from the world
  • Unipolar neurons: have a single long axon for sending electrical signals
• Cells of the Nervous System:

  • Glial Cells (Neuroglia):
  • Astrocytes: provide structural support
  • Ependymal cells: line ventricles of the brain
  • Microglia: phagocytic
  • Oligodendrocytes: form myelin sheath in the CNS
  • Schwann cells: form myelin sheath in the PNS
• Organization of the Nervous Tissue:

  • Gray Matter: contains cell bodies of neurons, receives and regulates information
  • White Matter: composed of axons, transmits signals to other regions of the brain and body
• Action Potential:

  • Resting membrane potential: electrical potential difference across the plasma membrane in a non-excited state
  • Depolarization: shift from negative to positive charge
  • Repolarization: return to a negative value after depolarization
• Synapses:

  • Connect neurons and help transmit information from one neuron to the next
  • Presynaptic neuron: transmits the signal toward a synapse
  • Postsynaptic neuron: transmits the signal away from the synapse
  • Synaptic vesicles: play a central role in synaptic transmission
• Synaptic transmission involves key organelles that play a central role in functions such as uptake, storage, and release of neurotransmitters
• Intracranial volume is divided into Brain, CSF, and Blood & Blood vessel
• Meninges protect the brain and spinal cord, with layers including Dura mater, Arachnoid, and Pia mater
• Frontal Lobe is responsible for controlling abilities like thinking, movement, memory, social skills, and interaction with others
• Parietal Lobe integrates sensory information such as touch, temperature, pressure, and pain
• Occipital Lobe is associated with visual processing, visuospatial processing, and memory formation
• Temporal Lobe manages emotions, processes sensory information, stores memories, and understands language
• Brain Stem connects the cerebrum to the spinal cord and cerebellum
• Thalamus relays sensory input to the cerebrum and plays a role in sleep, wakefulness, consciousness, learning, and memory
• Cerebellum is responsible for muscle control, balance, movement, language processing, and memory
• Spinal Cord sends motor commands from the brain to the body, receives sensory information, and coordinates reflexes
• Hypothalamus receives chemical messages, maintains internal balance, and plays a role in emotions
• Hippocampus is involved in memory, learning, and emotion, transferring short-term memories to long-term storage
• Pituitary gland is the "master gland" regulating bodily functions through hormone production
• Corpus callosum allows information transmission between brain hemispheres, playing a role in movement control, cognitive functions, and vision
• Cerebral cortex is responsible for higher-level brain processes like language, memory, reasoning, emotion, and personality
• Midbrain plays a crucial role in processing visual and auditory signals, involving movement and cerebral cortex pathways
• Pons relays and regulates pain signals from the body below the neck
• Medulla manages heart, circulation, and breathing, controlling heart rate, blood pressure, and more
• Skeletal muscles include Skeletal, Cardiac, and Smooth types
• Muscles have parts like Origin, Belly, Insertion, and are connected to bones by Tendons
• Bone structure includes Epimysium, Endomysium, Perimysium, Compact Bone, and Cancellous bone with trabeculae
• The Skeletal System is divided into Axial (head, neck, back, chest) and Appendicular (limbs, pelvis, scapula)
• Muscle contraction sequence involves synaptic vesicle release, diffusion of neurotransmitters, and muscle cell membrane permeability changes
• Classification of bones includes Long, Short, Flat, and Irregular types