Chapter 3: CNS Structure And Function

Question 1

What does somatic system

Answer 1

• it controls voluntary muscles and conveys sensory information to the central nervous system
• It is blue blood
• Part of peripheral nervous system

Question 2

What does autonomic system do?

Answer 2

• It controls involuntary muscles
• Has sympathetic(expends) and parasypmathic(conserves)
• part of peripheral nervous system

Question 3

Steps of somatic nervous system

Answer 3

Sensory receptor —> sensory input(PNS) —> integration (brain and spinal cord CNS) —> Motor output (peripheral nervous system —> effector cells in muscle

Question 4

What is the function of the sympathetic nervous system?

Answer 4

• It is a network of nerves that perpares the organs for rigorous activity
• Increases heart rate, blood pressure, respiration etc. (fight or flight)
• mainly uses norepinephrine as a neurotransmitter at the postganglionic synapses

Question 5

What is the infection of the parasymphathetic nervous system?

Answer 5

• It facilitates vegetative, non emergency responses.
• decreases functions increased by sympathetic nervous system
• mainly uses acetylcholine as the neurotransmitter at the postganglionic synapses.
• dominant during our relaxed states

Question 6

Neuraxis

Answer 6

Imaginary line drawn through the CNS as a reference for communication of neuroanatomical location

Dorsal = top
Ventral = bottom
Both sides are lateral and medial
Poster back, anterior front

Question 7

Electroencephalogram (EEG) function

Answer 7

• billions of neurons produce very small electrical signals that form patterns called brains waves
• small sensors are attached to your head that detect brains waves from the thousands of neurons immediately below = summated electrical potentials
• the EEG machine amplifies the signals and records them

Question 8

Pneumoencephalogram

Answer 8

Air is introduced into CSF circulation and the x ray imaging permits ventricular spaces within the space to be observed

Question 9

Computed Tomography (CT)

Answer 9

• Scans of sections of tissue in 360 degree are obtained and made into a whole image from the compilation of the slices … like slices of a loaf of bread. Tissues absorb different amounts of x ray radiation and appear different; bone appears white, soft tissue is gray and air is black.

Question 10

Positron Emission Tomography (PET)

Answer 10

A short lived radioactive tracer isotope is injected into the blood circulation. The tracer is fluorodeoxyglucose (FDG), a sugar, which is taken up into metabolically active brain tissues. Radioactive emissions are detected when they reach a scintillator in the scanning device. During the scan a record of tissue tracer concentration is made as the tracer decays. Computer performs a 3-D reconstruction of images taken serially throughout the brain.

Question 11

PET scans of CNS Pleasure Centers

Answer 11

During induced laughter the same brain areas are activated as are by amphetamines, cocaine, monetary reward, and attractive faces.

Question 12

Magnetic Renosance imaging (MRI)

Answer 12

• Uses radio waves and a strong magnetic field to provide clear and detailed images
• Magnetic field is used to align the brain hydrogen ion atomic nuclei
• Then, radio frequency magnetic fields are applied to systematically alter the alignment of this magnetization —> causes rotating magnetic fields detectable by the scanner.
• different tissue depths oscillate at different speeds

Question 13

FMRI

Answer 13

• In an fMRI a cognitive task is performed when imaging is taking place. The blood flow in the area responsible for performing this task will increase and the signal in the image will change similarly.
• thus, brain activity in the fMRI image is based on the blood floe to the local vasculature and the oxygen extraction that accompanies the brain activity.
• By performing specific task that correspond to different functions, it is possible to locate the corresponding are of the brain that governs the function

Question 14

Telencephalon

Answer 14

• part of the forebrain
• one of the last parts of the brain to mature
• cerebral cortex

Question 15

Corpus collusm

Answer 15

Connects the two hemispheres and allows for communication between the sides

Question 16

Alzheimer’s

Answer 16

• Sucli are enlarged in Alzheimer’s because degradation of cerebral cortical cells and shrinking on brain
• memory loss occurs because hippocampus is attacked first, part of lambic system and telecephlolon

Question 17

Movement

Answer 17

Input comes in through the sensory organs, goes from those receptors to the thalamus in the diancelelon major relay center of brain —> primary center cortex (auditory to auditory cortex, etc), then it goes to the second cortex where we make a plan for movement, whether and how to respond, then goes to primary motor cortex where we activate subcortical motor pathways then out the information goes through somatic nervous system to a skeletal muscle

Question 18

Does brain size mean higher intelligence?

Answer 18

• intelligence is due to the brains underlying organization and molecular activity at its synapses.
• What counts is that neurons are available for learning, remembering, reasoning, and making plans.

Question 19

Cerebral hemispheres

Answer 19

Each hemisphere receives sensory information from and controls movement of the opposite side of the body

Question 20

Homotopic callosal pathways

Answer 20

Like structures in the left and right hemispheres are directly connected

Question 21

Primary associational cortex

Answer 21

• each lobe has a primary associational cortex
• primary cortex in the sensory lobes provides initial processing resulting in awareness

Question 22

Secondary associational cortex

Answer 22

• Each lobe has a secondary associational cortex
• secondary cortex does more in-depth processing resulting in comprehension

Question 23

Flow of information through the cortex

Answer 23

Sensory organs —> thalamus —> first sensory —> second sensory —> AG —> second motor —> first motor —> subcortical motor pathways —> skeletal muscle

Question 24

Wernickes aphasia

Answer 24

Speech comprehension deficit unrelated to auditory dysfunction

Question 25

Wernickes and Broca’s areas in human speech

Answer 25

Wernickes area -> Broca’s area -> primary motor cortex -> speech

Question 26

What does the lambic system do?

Answer 26

• Consists of a number of interlinked structures that form a border around the brain stem
• it serves to mediate motivation, emotion, drives and aggression
• includes the olfactory bulb, hypothalamus, hippocampus, amygdala, and cingulate gyrus of the cerebral cortex

Question 27

What basal ganglia do?

Answer 27

• Subcortical motor control
• Associated with planning of movement and aspects of memory and emotional expression
• comprised of the caudate nucleus and put amen and globes pallidus

Question 28

Diencephalon

Answer 28

Thalamus major relay station receiving

• info from sensory organs and forwarding this input to the cortex and
• motor output from the cortex and forwarding it to the muscles

Question 29

Hypothalamus

Answer 29

• below the thalamus, is a small area near the base of the brain
• associated with eating, drinking, sexual behavior, and other motivated behaviors
• conveys messages to the pituitary gland to alter the release of hormones influencing endocrine organs (ovaries/testes, adrenals, bone)

Question 30

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