They found a drug, that erases memories.
They trained some mice to avoid a trianglular area of their pen by giving them a shock every time they got into the area. They gave a drug they referred to as Zip, and the mice permanantly forgot about the shocks from the triangular area.
They said right now. it is like erasing the hard drive. they want to see if they can find a way to be very selective on the memory erasure, such as removing memories of tramatic incidents.
Being mostly a science fiction person, my mind went wild with the concept.
Of course, I don't know the nature of the drug, whether it is only an injectable, or can be taken orally, or what kinds of conditions it is kept under. I will assume the best for the concepts.
The bad guy gets a stockpile of the drugs and slips it into some food that a good portion of the elite or power people eat. They start having memory problems which allows the bad guy a chance to take over.
the drug is used in hollywood. The actors forget their past, forget people they knew, but are able to learn their lines and their handlers guide them through the life expected of being popular, so no one ever knows the difference.
The politicians have created a medical system where people must see the doctor every month. When a politician messes up, and the people start to complain about the mistakes, the people are given an amount of the drug that fades the recent memories so they forget all about the mistakes when the next election is coming up. there are always those who are activists. They are cleared more and more until they stop being activists or are activists for inconsiquencial things.
Aliens have an attack that is quite effective. An energy is sent out to cause extreme irritation among the population. Little things become disasters for the people. real disasters become debilitating. The aliens are sending a rain of small asteroids to cause real disasters in some parts of the country.
Scientists use the memory erasing drug in small doses to remove the most recent memories of disaster victims so they can start to function again. The population is kept busy, the aliens are kept away because our society is able to continue to operate, to prepare for a real war.
This is just a few I thought of in the past half hour. Maybe some of you can come up with others, or use what I have already suggested.
Here's one link to a news story, though I'm sure there are others.
http://abcnews.go.com/Health/Story?id=2964509&page=1
Motor control is apparently not affected. What about learning, language, personality, identity? What are it's limitations? Short-term memory isn't affected. And apparently long-term memory storage recovers once the drug leaves the brain. The issue of selective erasure doesn't seem to be insurmountable. Localized brain activity can be tracked related to memory recall. However, the possibilities for abuse are ripe. At least the availability of the drug is not widespread. If it were a naturally occurring or easy to make drug, people would have been losing their long-term memories for some time. Imagine the drug on the black market.
"Name?"
"John Doe."
"And, John, where'd ya get the Zip?"
"Can't remember."
"How about a plea bargain? You tell us who you got the Zip from, and we'll ignore the fraud and money laundering charges."
"Fraud? Money laundering? Charges?"
"You are John Doe, right?"
"I am?"
If that's the case, it's not only traumatic memories (combination of chemicals and neural connections?) that are the problem. Another problem would be a person's inability to cope with memories in such a way that they can rebuild their pathways to direct more "positive" than "negative" information. Removing the memory without rebuilding the pathways could actually hinder a person's long-term health, as they would continue to deal with the negative consequences (e.g., panic attacks) without knowing how to address the problem--as they wouldn't remember the source.
It's difficult to be happy when you feel like something's wrong with you and you can't determine what it is.
A person's personality is not likely to change drastically with the loss of memory. A good person will continue to be good, unless they are the kind of people who put on a front, being nice and considerate to you and really a total jerk when you are not around. there are a lot of those and I would assume they would become their true self instead of showing their shell.
Things they would retain their muscle memory. If there was something they did as part of their job such as type , jog, work with machines, drive, bicycle, hammer metal, they will just need to show the basics of it to be able to do it as well as they did before. It is muscle memory that allows us to be doing something complex while letting our minds wander.
With all ethical questions on science, it all depends on who is in control over the results. There are a few entities that are immune to the law and can do things that ethicists are worried about and no one can stop them. The trick is to keep those entities away from questionable science so the laws can be used to prevent abuse.