Stocks spurted ahead early Thursday but gave back about two-thirds of the morning’s gains. The Nasdaq closed with a 0.5% gain after being up 1.6%. The S&P 500 and IBD 50 also added 0.5%. Volume slipped on the NYSE but edged up on the Nasdaq. Turnover was fast during the morning ascent and then dropped off during the afternoon retreat. So the volume action remained bullish, although the uptrend remains under pressure.