Brain Flashcards
What is a meninge?
Connective membrane that surrounds CNS
How many membranes do mammals have?
3
Dura mater, arachnoid, pia mater
What are the three main divisions of the brain?
Prosencephalon, Mesencephalon, Rhombencephalon
What are the divisions of the prosencephalon (forebrain)?
Telencephalon (cerebrum)
Diencephalon (epithalamus, thalamus, hypothalamus)
What do the Mesencephalon (midbrain) consists of?
Tectum and tegmentum
What are the divisions of the rhombencephalon (hindbrain)?
Metencephalon
Myelencephalon
What is the Myelencephalon? (hindbrain)
Medulla oblongata
Nuclei for CN 5-10/11
pathway for ascending and descending fiber tract
Contains center for regulating heart beat, blood pressure, intestinal motility, pulmonary respiration
What is does the Metencephalon consist of? (hindbrain)
Pons and cerebellum
What does the pons do?
Only in mammal s and is the pathway for ascending and descending fiber tracts
What does the cerebellum do?
Connected to brainstem via cerebellar peduncles
Receives proprioceptive and equilibrium info
Integrates inputs to contribute to fine motor
What is the Mesemcephalon? (midbrain)
Tectum: 2 optic lobes and 2 auditory lobes (cororaquadrigemin)
tegementum: nuclei of CN 3 and 4
What is the epithalamus? (forebrain, diencephalon)
Includes pineal gland which effects skin pigment, photoreception, biological rhythms
What is the thalamus? (forebrain, diencephalon)
major rely center for all sensory impulses from spinal cord, hindbrain, midbrain to telencephalon
What is the hypothalamus? (forebrain, diencephalon)
Endocrine connection
Regulates body temp, water balance, appetite, and sexual behavior
What is the pituitary gland?
Protrusion off hypothalamus
divided into adenohypophysis and neurohypophysis
What are the two embryonic sources of the pituitary gland?
Neurohypophyseal bud and Rathke’s pouch
What is the cerebrum? (forebrain, telencephalon)
Similar basic structure in all vertebrates
Has 2 region
-pallium for sensory
-sub-pallium for motor
Describe fish cerebrum
Pallium: sensory area for receiving and processing olfactory
Subpallium: Motor area, receives all input from pallium and thalamus, sends efferent to innervate lower motor neurons
Describe amphibian cerebrum
Pallium: medial, dorsal, lateral
Subpallium: Gives rise to nuclei like globus pallidus and striatum, coordinates movement of limbs
Describe reptile cerebrum
Pallium: has large expansion of lateral pallium becoming the DVR
Subpallium: sends Sends efferent to innervate lower motor neurons
What is the function Dorsal ventricular ridge?
Receives and processes visual, auditory, somatic sensory info from thalamus
Sends efferents to globus pallidus and striatum of subpallium
Describe Bird cerebrum
Reptilian like
Dorsal part of DVR expands further to form the wulst for stereoscopic vision
Describe mammal cerebrum
Dorsal pallium expands to form neocortex
Hemispheres connected by corpuscallosum
Afferent sent from thalamus to cortex
Efferent from cortex to basal nuclei and lower motor neurons
What is the basal nuclei?
Involved in coordination of movement
Has three parts: globus pallidus, striatum, substantia nigra
Medial pallium associated with olfactory
Lateral pallium forms piriform cortex of cerebrum
What does the piriform cortex do?
Primary olfactory cortex and receives olfactory info
Contains uncus
What is the ancient olfactory pallium in fishes homologous with?
Hippocampus which is part of the limbic system involved wit memory and emotion
WHat pathway does CN 11 take?
motor fibers enter skull through foramen magnum to join fibers from medulla then exits through the jugular foramen
What are occipitospinal nerves?
1 or more pairs of nerves between vagus and first spinal nerve in fish
Only motor rami (ventral)
What forms the hypobranchial nerve in fish?
occipitospinal nerve ventral rami
What are lateral line cranial nerves?
Somatic sensory and electroreceptors that originate in the medulla and innervate the lateral line
6 pairs
