The Brain Attic

Yes of course! So SSRI is an abreviation for Selective Serotonin Reuptake Inhibitor. Prozac is probably the most well known example of an SSRI medication used to treat depression, anxiety, easting disorders and sometimes PTSD. 

To understand how SSRIs work, we first need to look at where it takes effect. SSRIs work in your synapses; the gaps between neurones where neurotransmitters diffuse across to send a signal. And as I am oh so nice I’ve a made a some diagrams to explain:

Structure of A Synapse:

As you can see, when an impulse travels along the first neurone (known as the presynaptic neurone), it is stimulated to release neurotransmitters, in this case serotonin, across the gap (known as the synaptic cleft). These neurotransmitters then move by diffusion across the gap and bind to their receptors on the next neurone, known as the post-synaptic neurone. If enough neurotransmitter binds in a given time, the signal will then be carried down through that neurone (keyword here is enough; there is a threshold and if that is not met/exceeded, NO impulse AT ALL will be generated in the postsynaptic neurone). Since serotonin is a neurotransmitter that contributes to feelings of wellbeing, this resulting impulse promotes a generally good mood. However, serotonin tends to lack in those with depression which means it is harder for them to generate such impulses (as it is harder to meet the threshold). So how do SSRIs fit in and work to compensate for this? 

The Process Of Reuptake

You’ll remember SSRI stands for selective serotonin reuptake inhibitor, in other words it stops serotonin from being absorbed back into the neurone it came from. This process is called reuptake. Reuptake happens through channels like the one shown in pink, where the serotonin molecules pass through so they can be used by the neurone again for the next impulse. 

The Action Of SSRIs

Week 19 of the deductionist training program.

Answer for retrograde analysis puzzle #3.

Answer retrograde analysis puzzle #3:

So this is a simple logic problem, it’s a quite hard creative problem. Most people have a hard time with this problem but I’ll try explaining this the best I can. If the bishop would stand on e4 there would be no black squared piece that would have moved. Which is a problem.

The white pawns couldn’t have moved. No piece have moved from white to black or from black to white. That means the white king couldn’t have moved because it can’t get out thanks to the pawns and couldn’t go to the white squares. If it castled it wouldn’t have been able to get back. So no black squared piece could have moved if the bishop is on e4. If that’s true none of those pieces could have captured any other piece either so there would be a black piece on a black square too, because there must have been a piece which captured all the other white pieces on the black squares, but there aren’t. A piece can’t capture and disappear afterwards.

“Two lions attack each other and eventually they eat each other so there is no remains left” - This isn’t possible, one lions remains must still exist.

So the bishop most be on e3.

You tell SM your conclusions and he tells you that you’re correct.