11 The Central Nervous System Flashcards
What are the parts of the brain during the fourth week of embryonic brain development from anterior to posterior?
Prosencephalon, mesencephalon, rhombencephalon, spinal cord
What are the areas of the brain in the fifth week of development from anterior to posterior?
Telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon
What secondary brain vesicles derive from the prosencephalon?
Telencephalon, diencephalon
What adult brain structures derive from the telencephalon?
Cerebrum and lateral ventricles
What adult brain structures derive from the diencephalon?
Epithalamus, thalamus, hypothalamus, and third ventricle
What secondary brain vesicles derive from the mesencephalon?
Mesencephalon
What adult brain structures derive from mesencephalon?
Midbrain (cerebral peduncles, corpora quadrigemina) mesencephalic aqueduct
What secondary brain vesicles derive from rhombencephalon?
The metencephalon and the myelencephalon
What adult brain structures derive from the metencephalon?
Pons and cerebellum. Anterior part of fourth ventricle.
What adult brain structures derive from the myelencephalon?
The medulla oblongate and the posterior part of the fourth ventricle
What are the meninges?
Connective tissue layers surrounding the brain and spinal cord.
What are the three meninges that surround the CNS?
The dura mater, arachnoid mater, and pia mater
What are the functions of the meninges?
Separate brain from skull. Enclose brain and protect blood vessels supplying the brain. Contain and circulate cerebrospinal fluid.
Name the ventricles of the brain.
Lateral ventricles
Septum pellucidum
Third ventricle
Fourth ventricle
Where is cerebrospinal fluid produced?
In the choroid plexus by the ependymal cells.
What are the functions of cerebrospinal fluid?
Buoyancy– reduces brain weight by 95%
Protection– liquid cushion
Environmental stability– transports nutrients, chemical messengers, and removes waste.
What is hydrocephalus?
Excessive cerebrospinal fluid flaking the ventricles and brain case.
What is hydrocephalus caused by and how is it treated?
Obstruction of CSF flow and intrinsic problems with arachnoid villi which drain CSF. Treated with ventriculoperitoneal shunts or endoscopic third ventriculostomy.
What is the location of conscious thought processes?
The cerebrum
What structure connects the two hemispheres of the cerebrum?
What type of structure is this?
The corpus callosum
Commissural tract
What type of brain matter is superficial on the cerebral cortex?
Grey matter
What makes up gray matter?
neuron cell bodies
What type of brain matter is deep in the cerebrum?
White matter
What makes up white matter?
Myelinated sheaths of axons.
What functions occur in the frontal lobe?
Decision making, personality, verbal communication, voluntary motor control of skeleton msucles
What functions occur in the parietal lobe?
Sensory interpretations of textures and shapes, understanding speech
What functions occur in the temporal lobe?
Auditory and olfactory experience
What functions occur in the occipital lobe?
Visual interpretation
What functions occur in the insula lobe?
Taste and memory
What are the functional areas of the cerebrum?
Pre-central gyrus, post-central gyrus, and association areas
What functions occur in the Pre-central gyrus?
Somatic motor control, contains primary motor cortex
What functions are located in post-central gyrus?
Contains somatosensory cortex. Somatic sensory control.
What is a homunculus?
A map of motor and sensory cortexes of the brain.
What are association tracts?
Areas that connect different parts of the same brain hemisphere
What are commissural tracts?
Areas that connect different hemispheres e.g. Corpus callosum
What are projection tracts?
Vertical areas that convey sensory and motor information.
What structures make up the diencephalon?
Epithalamus, hypothalamus, and thalamus
What kind of matter primarily makes up the diencephalon?
Gray matter
What structures make up the epithalamus?
Posterior roof of diencephalon and top of third ventricle. Habenular nuclei and pineal gland.
What are the functions of the habenular nuclei?
Relay signals from the limbic system, help in the visceral and emotional responses to odors
What is the function of the pineal gland?
Secretes melatonin to regulate circadian rhythms
What is the location of the thalamus?
Either side of the third ventricle
What is the thalamus’s function?
It serves a the principle rely point for sensory and motor information into cerebrum
What are the functions of the hypothalamus?
Effects and controls behavior, endocrine system, emotion, temperature control, sleep/wake cycles, hunger/ thirst, autonomic body control, and memory.
What structures are associated with the hypothalamus?
The infundibulum and the pituitary gland
What are the functions of the cerebellum?
Smoothes and coordinates body movements via information on equilibriums and posture, information on current movements, and proprioception.
What is proprioception?
The perception of your body parts’ spacial relations to each other.
What structures are associated with the cerebellum?
Cerebellar hemispheres, arbor vitae, and vermis
What is the brain stem?
The “primitive brain.” the bidirectional passageway between cerebrum and spinal cord.
What functions occur in the brain stem?
Autonomic and reflex centers essential for survival
What structures are part of the brain stem?
Mesencephalon, pons, and medulla oblongata
What is the medulla oblongata and what functions occur there?
Vasomotor center. Controls blood pressure through vasoconstrictions and vasodilation. Cardiac and respiratory center. Reflexes, coughing, sneezing, gagging, and vomiting.
What structures attach at the medulla oblongata?
The cranial nerves.
What is the limbic system and what functions is it associated with?
The “emotional brain”. Involved in memory, motivation, and energy
What structures are associated with the limbic system?
Cingulate gurus, fornix, anterior thalamic nucleus, septal nucleus, mammillary body, hippocampus, amygdaloid body, parahippocompal gyrus, olfactory tract, and olfactory bulb.
Where is gray matter in the spinal cord?
Deep.
Where is white matter in the spinal cord?
Superficial
What spinal cord structures are made up of gray matter?
Central canal, anterior, lateral, and posterior horns.
What spinal cord structures are made up of white matter?
Anterior, lateral, and posterior funiculi
What is Alzheimer’s disease?
Progressive degenerative disease of the brain.
What is the result and symptoms of Alzheimer’s disease.
Results in dementia. Symptoms are memory loss, depression, disorientation
What are the causes of Alzheimer’s disease?
Thought to be neurofibrillary tangles, the build up of amyloid precursor proteins, aka senile plaques.
What functions does Parkinson’s disease affect?
Affects muscle movement and balance
What are the symptoms of Parkinson’s disease?
Stiff posture, expressionless face, slow movements, resting tremor, shuffling gait.
What causes Parkinson’s disease?
Deficiency of neurotransmitter dopamine.
