This experimental investigation concerns the functioning of human attention. It is based on a replication of the famous “Stroop effect” produced in 1935 by John Ridley Stroop. The aim of this experiment was to demonstrate how difficult it is for a person to divide their attention into different tasks, by having participants read a series of three stimuli which consisted of: 1) colored words in black ink , 2) color words in their actual font color, and 3) color the words with a different ink, where the participant reads the font instead of the present word. The research hypothesis assumed that selective attention is as easy to achieve visually as it is audibly. The controlled variable of the experiment was the color of the words in black ink, while the second stimuli was considered as an experimental variable. There were two independent variables which were the color words corresponding to their color and the number of errors made by each participant in each category. The dependent variable was the third stimuli, where the participant read their font rather than the presented word. The experiment was carried out within a group of sixteen participants aged 13 to 16 (eight girls and eight boys in total). The average time and errors in each variable were as follows: 9.28 seconds with no errors, 9.53 seconds with one error, and 25.53 seconds with an average of two errors. In conclusion, the observations showed that it took much longer for the last stimuli, which were those that divided attention into two tasks. The involvement results would correspond to the minimum number of participants in the experiment. The aim of the experiment was to discover the implications of attention when used in two different tasks. This inve...... middle of paper ......my day at about the same time. They were also tested one by one, while the others remained in a classroom without exposure to what they would do when it was their turn. If the words were given in the participant's native language, the results would be more reliable because it was their most proficient language. Two of the participants had the experiment carried out later in another environment. Works Cited “BACKGROUND OF THE STROOP EFFECT”. Rochester Institute of Technology. Internet. Feb 16 2010. “BDoughertyAmSchool – IB Information – Grade 11.” BDoughertyAmSchool - home. Internet. Feb 16 2010. “Participant Selection -.” Participedia. Internet. February 16. 2010..