The USDJPY moved lower in the US session but after getting within 11 pips of the 100 hour MA. Since then the price has gone back to 157.84 now as the buyers have strong control. The last time the price tested the 100 hour MA was back on December 17th and December 18th before the FOMC rate decision. That decision helped push the price higher after that.
Yesterday a new high was reached dating back to July 17th. The price also moved to a swing area on the daily chart between 157.66 and 158.86. The area is extensive but is home to several swing levels. If the buyers are going to take even more control and possibly run to the high for the year at 161.94, it is necessary to get and stay above that level.