"margin call" sell off . "forced" to sell. Somebody's buying.
It seems the market thinks that stock prices should go up everday just like houses, there 250 trading days in a year if the dow rose just 10 points every session the Dow Jones 30 would add 2500 points a year. Once the market hits a new high investors feel that stocks should remain at that value and progress higher over time, but if the value falls a bit investor's fear begin rising. In an unmanipulated market prices should remain stable as real supply and demand factors drive stock prices but in a manipulated market like in the USA stock regulators have allowed the creation of many supply and demand distorters like margin,short selling and naked short selling. Shorting is mainly the deeds of wall street , they will short stocks then through media outlets create a little sell off and buy back the shares at the same time "margin calls" are going out to clients of Wall street firms, once all the margin calls are made and the buyers are "forced" to sell.
The fed monitors the total amount of stocks that are margined, the fed banks let jp morgan, goldmansacs know etc, at this time stocks can sell off with the "margin call" sell off. This type of sell off is easy to fullfill as most of the margin buyers are instructed to put stop loss orders in at a discount to what they just purchased the shares for. A build up of stop loss orders could trigger a "sell-off" as the orders change to market orders as the price drops each stop loss order pushes the stock price down until it hits support which is usally put there by short sellers to cover their trades, after this "wash out " is complete the stock can rise again as forced selling supply drys up. Computer market monitoring programs watch everything that will enable the manipulation, wall street even watches the amount of "quotes" of stocks to monitor "buzz".
Wallstreet will scare people into buying puts thus making the VIX index rise, but by option exp the market will recover or stabalize rendering huge profits on the puts for wall street not the people. At the same time the VIX is high wall street will close out open call positions and go long calls which makes the VIX "fall".
So buy low, buy , buy calls and sell puts all when the VIX is spiking.
Remember this 10 points a day gain on dow 30 would add 2500 points a year so expect a down day once in a while and a down week every couple months or so, have no worrys you know what to do , in every and i mean every sell off somebodys buying.