3.3 Stop And Check Flashcards
What determines whether ontogenetic stimulation excites or inhibits it?
Ontogenetic stimulation activates a light-sensitive protein.
If that protein opens a sodium channel in the membrane, the result is excitation of the neuron. If it opens a chloride channel, the result is inhibition
What is the difference between a lesion and an ablation?
A lesion is damage to a structure.
An ablation is removal of the structure.
For example, a blood clot might produce a lesion, whereas surgery could produce an ablation
What does fMRI measure?
It detects an increase in blood flow to a brain area immediately after an increase in brain activity, and it also detects a slightly slower increase in the percentage of hemoglobin lacking oxygen.
Suppose someone demonstrates that a particular brain area becomes active when people are listening to music. When that area becomes active later, what if anything can we conclude?
Without further evidence, we should not draw any conclusions.
Perhaps the person is listening to music again, but this area may perform functions other than listening to music.
A good test of how well we understand the area would be to find out whether we can use fMRI recordings to guess which type of music someone is hearing
(or whether they are listening at all)
What are the similarities and differences between MRI and fMRI?
Both methods measure the responses of brain chemicals to a magnetic field.
MRI shows the anatomy of the brain.
The fMRI method shows which brain areas are most active at the moment
Why are both brain size and brain-to-body ratio unsatisfactory ways of estimating animal intelligence?
If we consider ourselves to be the most intelligent species, we are confronted with the fact that we have neither the largest brains nor the highest brain-to-body ratios
Brain-to-body ratio depends on selection for thinness as well as selection for brain size
Furthermore, animal intelligence is undefined, so we cannot determine what correlates with it.
Why do recent studies show a stronger relationship between brain size and IQ than older studies did?
The use of MRI greatly improves the measurement of brain size, in comparison to measurements based on the skull
In which way do men and women differ most- intellectual performance, total gray matter, or total white matter?
Men have more white matter, and therefore larger brains.
However, men and women are equal in intellectual performance and nearly equal in gray matter.
