Exam 1: Slide 1 Flashcards
(84 cards)
The Compound Microscope
discovered in the 1600s-1700s; neural cells could be distinguished
Who proposed the theory of Phrenology?
Franz Joseph Gall; early 18002
Phrenology
a. That the brain was the source of behavior
b. Specific regions of the cortex correlated to specific function (i.e. generosity, religiousness, etc.)
c. With use, the brain region associated with a specific function grew (like a muscle), and the bumps on your skull reflected this
Camillo Golgi
Formulated the Golgi method
Golgi made incredibly detailed drawings of different neuronal types using this method
As a result of his work, Golgi helped support the reticular theory
The Golgi Method
usiing silver slats to stain whole neurons in the brain
Reticular Theory
stated that the brain was made up of a continuous network of neurons; supported by Golgi’s work; This was later disproved by Cajal
Santiago Ramon y Cajal
(late 1800s) – Spanish neuroanatomist
Improved upon the Golgi method
Cajal was able to show that neurons were individual cells that communicated with each other instead of a continuous network. This was known as the neuron doctrine
The Neuron Doctrine
Cajal was able to show that neurons were individual cells that communicated with each other instead of a continuous network and became known as this
Peripheral Nervous System
Classified based on some are all neuronal parts being located outside of a bony casing(i.e. not all contained within the brain and spinal cord); comprises axons that are bundled into what are called nerves, and cell bodies called ganglia
The PNS can be further divided into:
Somatic nervous system: communication with sensory organs and voluntary motor control and is largely under our conscious control; cranial and spinal nerves
Autonomic nervous system – communication with internal organs and is not under voluntary control
PNS: Somatic Nervous System
communication with sensory organs and voluntary motor control and is largely under our conscious control; cranial and spinal nerves
PNS: Autonomic Nervous System
communication with internal organs and is not under voluntary control
sympathetic and parasymapthetic
Cranial Nerves
- sensory and motor innervation for head and neck
- You have 12 pairs of cranial nerves, some are purely sensory (vision, smell and vestibulocochlear), some are purely motor (oculomotor, trochlear, abducens, spinal accessory and hypoglossal) and the rest are mixed (trigeminal, facial, glossopharyngeal and vagus)
- PNS: Somatic
Spinal Nerves
-sensory and motor innervation for the rest of the body
-You have 31 pairs of spinal nerves, broken in to 4 distinct segments: cervical (neck), thoracic (trunk), lumbar (lower back), sacral (pelvic) and coccygeal (bottom).
From each spinal cord section, you will have two types of nerve bundles going into or out of the spinal cord:
1. Dorsal root
2. Ventral root
Spinal Nerves Segment
cervical (neck), thoracic (trunk), lumbar (lower back), sacral (pelvic) and coccygeal (bottom)
Dorsal Root
sensory information coming in to the spinal cord on the dorsal (i.e. back) side
spinal nerves; nerve bundles
Ventral Root
motor information leaving the spinal cord on the ventral side (i.e. stomach) side
spinal nerves; nerve bundles
Autonomic Nervous System
communicates with internal organs and glands and is largely not under our conscious control.
comprised of the sympathetic and parasympathetic nervous system
PNS: Autonomic: Sympathetic Nervous System
“fight or flight”; cell bodies located in the vertebral column for the first neuron (preganglionic), which synapses onto a postganglionic neuron usually located in the sympathetic chain ganglia. This second neuron then sends its axons to a target gland.
The preganglionic fiber releases a neurotransmitter called acetylcholine, while the postganglionic releases a neurotransmitter called norepinephrine.
PNS: Autonomic: Parasympathetic Nervous System
-rest and digest; cell bodies located by target organs/glands (preganglionic), with the postganglionic neuron projecting to the target.
The preganglionic and postganglionic fibers release acetylcholine.
Central Nervous System
- contains your brain and spinal cord, which is the main focus of this class
- In the CNS bundles of axons are called tracts (pns=nerve), and clustered cell bodies are called nuclei (pns=ganglia)
Central Nervous System Grey and White matter
The myelin covering the axons tend to be white in appearance and the cell bodies grey, thus regions with cell bodies are called grey matter and regions with axons white matter.
The four major divisions of the CNS
forebrain, midbrain, hindbrain and the spinal cord
Forebrain
Gyri (gyrus=one)
Sulci (sulcus=one)
The cortex contains two hemispheres, a left and a right
layered structure, with 6 layers of neurons in humans.
Forebrain Gyri and Sulci
Gyri (gyrus=one) – cortical bulges that are divided by:
Sulci (sulcus=one) – grooves in between the gyri
The sulci and gyri allow humans to have a lot of brain tissue within our skull compared to other species.