A&P Chap 12 Flashcards
1
Q
What does CNS consist of?
A
Brain and spinal cord
2
Q
What is cephalization?
A
- Evolutionary development of anterior portion of CNS
- Resulted in increased number of neurons
- Highest level reached in human brain
3
Q
Embryologically, the brain and spinal cord begin as a __________.
A
Neural tube
4
Q
Neural tube’s anterior end expands, and constrictions form three primary vesicles:
A
- Prosencephalon (forebrain)
- Mesencephalon (midbrain)
- Rphombencephalon (hindbrain)
Posterior end becomes spinal cord
5
Q
Primary vesicles give rise to five secondary brain vesicles. Forebrain becomes…?
Midbrain? Hindbrain?
A
Forebrain: telencephalon and diencephalon
Midbrain: remains
Hindbrain: metencephalon and myelencephalon
6
Q
Telencephalon gives rise to ______?
A
Cerebral hemispheres (cerebrum)
7
Q
Diencephalon becomes …?
A
the epithalamus, thalamus, hypothalamus and retina
8
Q
Metencephalon becomes…?
A
The pons and cerebellum
9
Q
Myelencephalon becomes…?
A
Medulla oblongata
10
Q
Central cavity of neural tube becomes…?
A
The ventricles
11
Q
Adult brains have four regions:
A
- Cerebral hemispheres (cerebrum)
- Diencephalon
- Brain stem (midbrain, pons, medulla)
- Cerebellum
12
Q
Each of the cerebral hemisphere has three regions. What are they?
A
- Cerebral cortex gray matter
- Internal white matter
- Basal nuclei
13
Q
What is gray matter?
A
Short, nonmyelinated neurons and cell bodies
14
Q
What is white matter?
A
- Myelinated and nonmyelinated axons
- Primarily in fiber tracts
- The dense coating of fatty myelin gives white matter its color
15
Q
What is a basic pattern found in CNS
A
- Central cavity surrounded by gray matter, with white matter external to gray matter
- Brain stem has additional gray matter nuclei scattered within white matter
- Cerebrum and cerebellum contain outer layer of gray matter. called the cortex
16
Q
Elevated ridges of tissue is called…?
Shallow grooves are called…?
A
- Gyri
- Sulci
17
Q
What are the five lobes divided by several sulci?
A
- Frontal
- Parietal
- Temporal
- Occipital
- Insula
18
Q
What is cerebral cortex?
A
- Executive suite of brain
- Site of conscious mind; awareness, sensory perception, voluntary motor initiation, communication, memory storage, understanding
- Thin superficial layer of gray matter, composed of neuron cell bodies, dendrites, glial cells, and blood vessels but no axons
- 40% mass of brain
19
Q
What does functional imaging (PET and MRI) show?
A
Specific motor and sensory functions located in domains
20
Q
What does premotor cortex do?
A
- Helps plan movements; staging area for skilled motor activities
- Controls learned, repetitious, or patterned motor skills
- Coordinates simultaneous or sequential actions
- Controls voluntary actions that depend on sensory feedback
21
Q
What is Broca’s area?
A
- Present in one hemisphere (usually left)
- Motor speech area that directs muscles of speech production
- Active in planning speech and voluntary motor activities
22
Q
What is sensory areas?
A
- Areas of cortex concerned with conscious awareness of sensation
- Occur in parietal, insular, temporal, and occipital lobes
- Primary somatosensory cortex, somatosensory association cortex, visual areas, auditory areas, vestibular cortex, olfactory cortex, gustatory cortex and visceral sensory area
23
Q
What is vestibular cortex?
A
- Posterior part of insula and adjacent parietal cortex
- Responsible for conscious awareness of balance (position of head in space)
24
Q
What is olfactory cortex?
A
Involved in conscious awareness of odors
25
What is gustatory cortex?
Involved in perception of taste
26
What is multimodal association areas?
- Allows us to give meaning to information received, store in memory, tie to previous experience, and decide on actions
- Sensations, thoughts, emotions become conscious: makes us who we are
27
What is anterior association area?
- aka prefrontal cortex
- Involved with intellect, cognition, recall and personality
- Contains working memory needed for abstract ideas, judgment, reasoning, persistence, and planning
- Development depends on feedback from social environment
28
What is posterior association area?
- Plays role in recognizing patterns and faces and localizing us in space
- Involved in understanding written and spoken language (Wernicke's area)
29
What is limbic association area?
Provides emotional impact that makes a scene important to us and helps establish memories
30
What do left and right hemisphere control?
Left: language, math, and logic
Right: Visual-spatial skills, intuition, emotion and artistic and musical skills
31
What are functions of basal nuclei?
- Influence muscle movements
- Play role in cognition and emotion
-Regulate intensity of slow or stereotyped movements
- Filter out incorrect/inappropriate responses
- Inhibit antagonistic/unnecessary movements
32
What does diencephalon include?
- Thalamus
- Hypothalamus
- Epithalamus
33
What does thalamus do?
Acts to mediate sensation, motor activities, cortical arousal, learning, and memory
Sorts, edits, and relays ascending input such as:
- regulating emotion and visceral function
- help direct motor cortices
- memory or sensory integration
34
What does hypothalamus do?
- The main visceral control and regulating center that is vital to homeostasis
- Controls autonomic nervous system
Examples: blood pressure, rate and force of heartbeat, digestive tract motility, pupil size
- Initiates physical responses to emotions
Part of limbic system: perceives pleasure, fear, rage, biological rhythms, and drives (sex drive)
- Regulates body temperature: sweating or shivering
- Regulates hunger and satiety in response to nutrient blood levels or hormones
- Regulates water balance and thirst
- Controls endocrine system functions such as:
Secretions of anterior pituitary gland
Production of posterior pituitary hormones
35
What does epithalamus do?
- Contains pineal gland
- Secretes melatonin to regulate sleep wake cycle
36
What are three regions of brain stem and what is its functions?
- Midbrain, pons, medulla oblongata
- Controls automatic behaviors necessary for survival
37
Where is midbrain located?
Between diencephalon and pons
Periaqueductal gray matter: nuclei that play a role in pain suppression and fight-or-flight response
38
Parkinson’s disease is degeneration of ...?
Substantia nigra
39
Where is pons located?
- Between midbrain and medulla
- Some nuclei play role in reticular formation, and some help maintain normal rhythm of breathing
40
What is the function of medulla?
- Medulla is an autonomic reflex center
- Many functions overlap with hypothalamus
- Hypothalamus relays instructions via medulla
- Cardiovascular center: adjusts force and rate of heart contraction
- Respiratory centers: generate respiratory rhythm; control rate and depth of breathing
- Vomiting
- Hiccupping
- Swallowing
- Coughing
- Sneezing
41
What is cerebellum?
- 11% of brain mass
- Located dorsal to pons and medulla
- Processes input from cortex, brain stem, and sensory receptors to provide precise, coordinated movements of skeletal muscles
- Also plays a major role in balance
- Plays role in thinking, language, and emotion
