cogn psych m2 paper

What methods did we employ in this experiment?

On each trial of the experiment, a sequence of 19 letters was presented, with each new letter overwriting the previous one. Each letter was presented for only 100 milliseconds. Your task was to judge whether the letters J or K were in the sequence. The independent variable in this experiment was the temporal separation of the letters. On some trials, a K might have followed a J with only one letter in between. On other trials, a J might have followed a K with five letters in between. On some trials only a J or a K was presented.

What do we predict participants will do? Why?

The graph shows the percentage of times you detected the first and second target letters as a function of their separation. You should find that the second target is detected more frequently as separation increases. The curve for the second target should slant up from left to right. For separation zero, there was no second target, so the percentage reported should be close to zero. You should also find that the detection of the first target is relatively unaffected by separation. This finding supports the hypothesis that bringing attention to the first target interferes with detection of the second, but not vice-versa. Although the task in this experiment may seem rather absurd, it is quite similar to tasks some individuals must perform on a routine basis. In the airline industry, both pilots and controllers attend to many different stimuli that change characteristics very quickly. The temporal properties of attention revealed through studies like this one help guide development of more general theories of attention, with immediate applications to high-pressure situations.

How robust is this effect? Are there limits to this effect?

The attentional blink is quite robust. It can be observed with a wide variety of stimuli, not just letters. Attentional blink experiments have been used to study the effects of aging (Maciokas & Crognale, 2003) and Alzheimer's disease (Kavcic & Duffy, 2003) on attention.

Results on June 21, 2015 12:11:00 PM PDT

Data summary for experiment Attentional Blink.

The plot shows the percentage of times you reported seeing the first or second of the target letters (different lines) in the stream as a function of the separation between letters. A separation of zero means only the first letter was actually shown. The expected result is that the percentage of reports for the first letter do not vary much with separation. For the second letter, there should be few reports at separation zero, and the percentage of reports should increase with separation.

Data summary

Trial-by-trial data

The separation is the space between successive letters. A separation of 0 includes presentation of only the first target letter. Any reports of the second letter for a separation of 0 are mistakes. A response of J or K is indicated by that letter, a blank means neither J or K was given as a response.