Depression is usually characterized by extremes of these characteristics:
- lethargy, slow moving, lack of energy
- social withdrawal
- lack of sexual interest
- changes in eating habits
- excessive sleep
The manic states are the extreme opposite:
- Non stop speech
- lots of energy
- full of own self
- insomnia
- unrealistic in most thoughts and actions
Some studies have shown the heritability rate for bipolar disorder to be very significant. For monozygotic twins there was a 69 percent concordance rate, whereas for dizygotic twins it was only 13 percent.
There are many different levels of this disorder of course, some only containing depression and others only mania. But the underlying brain functions are relatively the same.
Let's go into a few of the treatments for this disorder.
Again, as with all of these complicated things I've been talking about, there is no way I can cover everything. And in case I butcher something, you might want to check this place out:
- MAO inhibitors
- Trycyclic Antidepressants
- Electroconvulsive Therapy
- Sleep Deprivation
MAO inhibitors work on the cellular level, in the synapses between neurons. It's a long complicated explanation but here's the quick and easy: People who have depressive symptoms are thought to have low levels of certain neurotransmitters. So, of course, the drug is going to try and raise those levels. Normally the brain releases certain neurotransmitters called monoamines, these are ones like, dopamine, norepinephrine, and serotonin. And also unsually, there is a substance called MAO that breaks these down. Now, if these patient's levels are already low, what do you think they could do to reverse that?
Yep, they found a substance that would block the MAO's from breaking down any more of those much needed neurotransmitters.
Trycyclic Antidepressants, of course work to reduce the depressive symptoms, and cheer 'em up a bit. Once again, since levels are low in these patient's brains they had to think of more ways to keep them flowing. So what they did was find a drug that let the neurotransmitters hang around longer in the synapse. That means that the receptors on the other side would a longer chance to "grab on". So the antidepressants block the reuptake of the monoamine, Norepinephrine.
Electroconvulsive Therapy was used because of its emmense storm of neural activity. This, believe it or not is still doing the same things as the other ones are, trying to keep the substance available. In this case the neural activity cause by the shock, allows Norepinephrine to flow more freely. Usually there are these things on the presynaptic membranes called autoreceptors and they regulate the anount of neurotransmitter substance released, so what happens during shock is, it inhibits those autoreceptors. Whereby letting more Norepinephrine be released.
The whole reason for depriving them of sleep, was to avoid the critical REM period, the state in which people dream. There are two types, selective and total sleep deprivation. Selective is when they wake the patients up right when they start to go into the dream, REM state. Total, is when they are not allowed to sleep at all. Their reasoning is that there is thought to be a brain substance released during sleep that causes some of the depression. The patients feel better after deprivation therapy, only to awaken after resuming sleep to be depressed.
So, there you go. Don't forget to read up more with the link I suggested above!!