anatomy Flashcards
The central nervous system contains…
the brain and the spinal cord
the peripheral nervous system is…
division located outside the skull and spine.
Somatic (of the body) nervous system- interacts with the environment
Autonomic (unconscious/ automatic) nervous system - regulates internal environment.
The divisions of the spinal cord:
CTLS
the cervical region- head, neck, diaphram, arms and hands
the thoracic region - chest, abdominal
the lumbar region- legs and feet
the sacral region- bowel and bladder control, sexual functions
The dorsal root
The unipolar sensory neurons are afferent neurons bringing sensory information via the dorsal roots to the CNS. They have their cell bodies grouped in the dorsal root ganglions. Each neuron has a peripheral process ending in the skin, a muscle or a joint (sensory receptor) and a central process ending in the dorsal horn of the spinal cord.
The ventral root
The mutlipolar motor neurons are efferent neurons sending motor information via the ventral roots to the muscles. They have their cell bodies in the ventral horn.
What are the 3 major subdivisions of the brain?
. Forebrain
. Midbrain
. Hindbrain
The forebrain
T: CBL
D: TH
Telencephalon
Cerebral cortex
Basal ganglia
limbic system
Diencephalon
Thalamus
Hypothalamus
Midbrain
M: T T
Mesencephalon
Tegmentum
Tectum
Hindbrain
M: P C
M: M
Metencephalon
Pons
Cerebellum
Myelencephalon
Medulla
The Medulla (Myelencephalon)
Contains tracts carrying signals from the brain to the body
- contains caudal part of the reticular formation
- low level sensorimotor control
- involved in a variety of vital functions
Pons
Metencephalon
Bridge
Relays from cortex and midbrain to the cerebellum
Cerebellum
Metencephalon
smaller than the brain but contains as many neurons as the rest of the CNS
corrects motor errors between intended and actual movement.
Tectum
midbrain- mesencephalon
Also called little hills. VIsual/ spatial and auditory frequency maps
Superior colliculus- sensitive to sensory change (orienting/ defensive movements)
Inferior colliculus
similar but for auditory
Tegmentum (3)
Midbrain- mesencephalon
The Periaqueductal gray (defense, reprodution, analgesia)
Red nucleus (target of cortex and cerebellum, projects to spinal cord, role in pre- cortical control in arms and legs)
Substantia nigra (dopamine cells) - basal ganglia input.. parkinsons disease. Substantia nigra pars reticulata- basal ganglia output
Diencephalon- (mid)
Thalamus
Relay structure.
Specific nuclei : relay signals to cortex/ limbic system for all sensations (but smell)
Non specific nuclei : role in regulating state of sleep and wakefulness
Important relays from basal ganglia and cerebellum back to cortex.
