In the short story "Flowers for Algernon," Charlie Gordon, like the mouse Algernon, receives an operation to improve his intelligence. They are both the first of their kinds to go through this process. Also like Algernon, it takes a while for Charlie to become more intelligent. Algernon becomes a super mouse, able to navigate mazes that no other mouse could, and Charlie's intelligence and knowledge skyrocket to genius levels. For example, he knows Hindustani and Chinese and understands the mathematical variance equivalent in Dobermann's Fifth Concerto.
However, over time, Algernon becomes uncooperative and no longer wants to run the mazes. Charlie notes that Algernon is starting to regress mentally, and that his glandular activity has slowed. In addition, he is showing signs of progressive amnesia, meaning he can't form new memories or learn new tasks. Charlie uncovers what he calls the Algernon-Gordon Effect, which states that one's intelligence (after one has gone through the surgery and become smarter) declines as rapidly as it increased. Algernon dies, and the dissection shows his brain had decreased in size. Charlie also begins to suffer from deterioration and can't remember what he learned recently. He becomes slothful and unmotivated, and he can no longer understand the books he once read. He returns to his old janitorial job, and he asks his former teacher to place flowers on Algernon's grave, as Charlie fears his own death is also near. Both man and mouse go through the same process of rapidly increasing their intelligence and then going through a rapid decline, and their lives are sacrificed to science.
In the book Flowers for Algernon the experiences for Charlie and Algernon were similar and different. Algernon had always been smart. He was able to demonstrate his intelligence by quickly moving through the maze. Charlie had a brain that mentally challenged with an IQ of 68. When tested against Algernon, he could not respond as well.
The first thing that they both have in common is that they are needed by the scientists for the experiment. In this sense Charlie is no less of a lab rat than Algernon. He does not really have value to the scientists other than for the results of their experiment. The scientists want to use the results for publication and to promote their careers. Charlie and Algernon both experience test after test.
As Algernon's mental status begins to deteriorate, Charile begins to under stand through his own research that he too will be returning to his prior state of inferior intelligence. He is upset but he relates to Algernon who also had to struggle with diminishing abilities until he dies.