In the 1960s, the psychologist showed that participants could recall 76% of the letters briefly flashed on a screen. The findings from his study indicate visual impressions in are photograph-like in nature. Shiffrin; iconic Shiffrin; echoic Sperling; echoic Sperling; iconic

Sperling; iconic.

Explanation:

In 1960, George Sperling performed several experiments to show the existence of iconic memory which is the subtype of sensory memory.

In his experiment in the 1960s, Sperling used a tachistoscope that was used to improve the reading speed of people. He flashed an image on the screen for less a second and observed that his participants were able to recall only 3-4 letters out of 12 letters displayed. The visual impression was named visual icon or iconic memory.

So, the correct answer is Sperling and iconic.