Lecture 2 (neuroanatomy and imaging) Flashcards
How is the nervous system divided?
CNS and PNS
What does CNS include?
The brain (encephalon) and the spinal cord.
What does PNS include?
The autonomic nervous system and the somatic nervous system.
What does the autonomic nervous system include?
The sympathetic, parasympathetic, and the enteric nervous system.
What does the somatic nervous system consist of?
The cranial nerves and spinal nerves.
What is the enteric nervous systems job?
To regulate the gastrointestinal channel.
What are neurons?
Excitatory cells that can send electrochemical signals from one cell to another.
Dendrites - output or input?
Input.
Axons - output or input?
Output.
What do glia cells?
They support the neurons’ functions. They are involved in immune response, myelinization, input of substance.
Which kind of glia cells exist?
Mikroglia, astrocytes, and Oligodendrocytes
Mikroglia?
Works as macrophages. They eat those cells that we don’t want.
Astrocytes?
Regulates the blood supply to neurons.
Oligodendrocytes?
Myelinization of the cells in the CNS
Parietal lope?
the experience of space. Sense of touch.
Occipital lope?
vision. V1-V5 is vision areas.
Temporal lope?
placed close to the ear. Hearing and sense of smelling. The big memory system is found medial in this lope. Hippocampus.
Frontal lope?
the motoric areas. Executive functions.
Brainstem?
pulse. Can’t live without.
Ventricles?
fluid filled space. Protecting of the CNS. CSF is produced in the lateral part of the ventricles.
The basal ganglia?
subcortical nucleus. Motoric control, procedural learning, habits.
The basal ganglia has a strong connection to cortex - with which functions?
motoric function, rewards, executive functions.
What happens in the basal ganglia with Parkinson’s disease?
loss of dopaminergic neurons in striatum.
The limbic system?
no one agree how to divide the limbic system. There is a big overlap between hippocampus and amygdala in this system. Much about the emotional functions and memory.
What does the diencephalon consist of?
Thalamus and hypothalamus.
Thalamus?
the brain’s switchboard. Many of the sensory signals come here through.
Hypothalamus?
central for homeostase. Control over the endocrine system via pituitary gland.
Hippocampus?
used when in need to get around. Used to make mental images.
CT?
x-ray is used to make the images. It measures how much radiation there is on the other side. It depends on the tissue how much radiation is coming through. 2-dimensionel images.
MRI?
you take advantage of the fact that the different types of tissue have different magnetic features. The magnetic field rectify all the magnets that have hydrogen atoms in them when scanning. Afterwards, you put on a secondary magnetic field which force all of these protons down in a horizontal position.
What are the structural imaging techniques?
CT and MRI
What are the functional imaging techniques?
EEG, PET, single photon emission CT, fMRI
EEG?
you look at the sum of rhythmic changes in cortex. Good for looking at sleep, epilepsy, consciousness.
PET?
you get an injection with a tracer in the blood. This tracer sends out positrons which attracts the electrons.
Single photon emission CT?
the tracer sends out gamma radiation which is measure directly. Otherwise, it is much alike PET
fMRI?
these images are layered over the structural MR-images (to get a higher solution). Is often build on the difference images between two conditions.
Advantage of MRI?
no x-ray/radiation. Higher spatial solution.
Advantage of CT?
cheaper. Faster. Less noise. Fewer problems with claustrophobia. No magnetic impact.
What are the steps in doing fMRI?
When analyzing the images, you use “smoothing” of data. This is used to reduce unnecessary noise. In the images, you will know see clusters of activity instead of small dots all over the place. It also reduces the effect of anatomical differences in the people.
What is the neuron doctrine?
The fact that cells of the brain are independent from one another structurally, metabolically, and functionally.
Glia cells and schizophrenia?
Changes in all three kinds of glia cells are implicated in the onset and symptoms of schizophrenia.
What do motor nerves do?
Transmit information from the spinal cord and brain to the muscles, organs, and glands.
What do sensory nerves do?
Convey information from the body to the spinal cord and brain.
Which communication does corpus callosum enable?
Communication between the right and left cerebral hemispheres.
What does grey matter do?
primarily receives and processes information
What does white matter do?
mostly transmits information to other locations.
Cerebellum?
crucial for motor coordination and control but also in aspects of cognition, including learning.
Medulla?
marks the transition from the brain to spinal cord. Contains nuclei that regulate breathing and heart rate.
What is circle of Willis?
an alternate route for blood flow if any of the main arteries to the brain should be damaged or blocked by disease.
Ligand?
any substance that binds to a receptor.
Agonist?
this form of ligand initiates the normal effects of the transmitter on that receptor.
Antagonist?
a ligand that binds to a receptor but without activating it.
Inverse agonist?
a ligand that binds to the receptor but has the reverse effect than normally.
Which effect does GABA have?
An inhibitory effect.
Where is dopamine especially found?
Midbrain.
Norephinephrine (noradrenaline)?
Contributes to diverse behavioral and physiological processes, such as mood, overall arousal, and sexual behavior. Used in the sympathetically nerve system.
Serotonin?
implicated in the control of sleep states, mood, sexual behavior, anxiety, and many other functions. Many antidepressants’ drugs share an action on serotonin; they act to increase its synaptic availability.
What is binding affinity?
the degree of chemical attraction between a ligand and a receptor.
Typical antipsychotics are good at?
The typical ones are good at relieving the positive symptoms from the disease.
Atypical antipsychotics?
The atypical ones seem to reduce the negative symptoms.
How does antidepressants work?
Normally, MAOs break down monoamine neurotransmitters at axon terminals, thereby reducing transmitter activity. By blocking this process, MAO inhibitors allow monoamine neurotransmitters to accumulate at synapses with an associated improvement in mood.
Depressants?
Used to help with anxiety. It is drugs that depress or reduce nervous system activity. Alcohol and opiates are perhaps the original anxiolytics.
Telencephalon?
The same as cerebrum.
Mesencephalon?
Cerebral penduncles, superior colliculus, and inferior colliculus.
Metencephalon?
Pons and cerebellum
Myelencephalon?
Medulla oblongata
