Final answer:
The P20-P50 attention effect is a demonstration of inattentional blindness, where individuals fail to notice visible elements in their environment when they are focused on a different task, as shown in studies by Daniel Simons and Christopher Chabris.
Step-by-step explanation:
The P20-P50 Attention Effect
The P20-P50 attention effect is related to the phenomenon of inattentional blindness, which is the inability to perceive features in a visual scene when the focus of attention is directed towards a different, specifically assigned task. This was famously demonstrated in a study by Simons and Chabris (1999) involving participants watching a video and failing to notice a gorilla because their attention was directed at counting basketball passes. A related study involving a red cross and black or white objects showed a similar effect. This reveals how selective our attention can be and how it leads to missing other visible information when we are deeply focused on a particular task.
Our cognitive system prioritizes attention and often employs mental shortcuts, known as heuristics, to efficiently process the vast amount of information we encounter. When engaged in attention-heavy tasks, especially if they are novel or complex, we may not process stimuli outside of our focal point, which can also be affected by fatigue, stress, or anxiety.