Section 9 Final Flashcards
Define sensation
the conscious or subconscious awareness of a stimulus
What are the 3 different types of general senses?
Somatic Senses, Visceral Senses, & Special Senses
What is epilepsy?
a disorder characterized by short, recurrent, periodic attacks of motor, sensory and psychologic malfunction
What initiates epilepsy attacks?
these attacks are initiated by abnormal, synchronous electrical discharges by numerous neurons in the brain which leads to seizures (i.e. uncontrolled nervous activity)
What causes epilepsy?
a wide variety of causes, ex. brain trauma, infection, metabolic disorders, etiology unknown, etc….
What is Quadriplegia?
paralysis of all limbs
What is Hemiplegia?
paralysis of one side of the body (e.g. upper limb, torso, lower limb)
What is Paraplegia?
paralysis of the lower limbs
What is Monoplegia?
paralysis of one limb
What is Transection?
severing of all or part of the spinal cord
What is Paralysis?
loss or impairment of motor function
What are first order neurons?
conducts the nervous impulse from the somatic sensory receptor to the CNS (Brain Stem or Spinal Cord)
What are 2nd order neurons?
conduct the nervous impulse from First Order Neurons to the Thalamus on the opposite side of the body
Where do the 2nd order neurons cross over?
these axons will cross over at the Spinal Cord or the Brain Stem
Where do the First and Second Order Neurons synapse?
in the Brain Stem or Spinal Cord
What is the function of Third Order Neurons?
conduct nervous impulses from the Thalamus to the Primary Somatosensory Area (Postcentral Gyrus) on the same side
Where do Second and Third Order Neurons synapse?
in the Thalamus
Where are Lower Motor Neurons (LMN) located?
cell bodies are located in the Brain Stem or Spinal Cord
What do Lower Motor Neurons (LMN) transmit?
transmit the nerve impulse to skeletal muscle
Where do Upper Motor Neurons (UMN) originate?
originate in the Precentral Gyrus and the surrounding area
Where do Upper Motor Neurons (UMN) descend/ crossover?
these axons descend to the Medulla Oblongata, most of these cross over to the other side of the body (i.e. decussate)at this level, the remaining axons will cross over in the spinal cord at the level where the nerve impulse exits the CNS
What is the function of Somatic Motor Pathways?
transport nerve impulses associated with movements from the brain
What is the function of Somatic Sensory Pathways?
these relay information from the somatic sensory receptors to the brain
What are Nociceptors?
respond to damage to tissue, i.e. pain receptors
What is adaptation?
a decrease in sensation when a receptor is constantly stimulated
What are the different types of sensory receptors?
Free nerve endings, Encapsulated nerve endings, & Separate cells
What are free nerve endings?
bare dendrites that have no apparent structure
EX: Thermoreceptor (sense temperature change)
What are encapsulated nerve endings?
dendrites enclosed in a connective tissue capsule
EX: Pressure receptor
What is the function of separate cells?
these are designed to receive a specific stimulus
EX: Photoreceptors
What are somatic senses associated with?
associated with the body
EX: pain receptor
What information do Visceral Senses provide?
provide information about the conditions within internal organs
EX:chemoreceptor
Where are the receptors of Special Senses located?
receptors are located in complex sensory organs that are located in specific regions of the body
EX: sight, hearing
Define Perception
the conscious awareness and the interpretation of the meaning of sensations
What are Modalities?
each unique type of sensation, a neuron is associated with only one modality
EX: pain, touch
What are the different classes of modalities?
- General senses:
- somatic
- visceral - Special senses
