Why you're picking the wrong answer on the MCAT

By Henry

While many students blame incorrect answers on a lack of knowledge or careless mistakes, these explanations don’t account for the many ways an MCAT test writer can mess with a poor unsuspecting test-takers brain. If the MCAT were a simple matter of knowledge and diligence, the studying process would be far easier. Knowledge is easily acquired (though less easily remembered, for more details see this post on memory) and diligence is easily drilled (see this post here on diligence). If you want to see a higher MCAT score, you need to acknowledge it’s a little more complicated than it looks. 

Why I started to look deeply at my mistakes:

During the course of my own studying, I spent weeks learning content and taking practice exams without seeing my score significantly improve. Being the sadomasochistic pre-med student that I am, I placed the burden of responsibility exclusively on myself in rather blunt ways. Why did I think I missed problems: carelessness, stupidity, tiredness, bad memory, lack of logic, naivety, or maybe lack of discipline. In short, I attributed my bad performance to personal qualities.

Luckily, I had an experienced tutor (from Cambridge Coaching, in fact) who had been in my position, and gave me some of the best advice I ever received: “don’t give yourself so much credit.” He went on to explain that because of the way the MCAT is written, one can easily fall victim to tricks of the mind that will skew my perceptions. Instead of blaming difficult-to-change personal qualities, I should look at these mistakes as evidence of normal tendencies (felt to some extent by everyone) that I needed to learn to counteract. By approaching my mistakes in this fashion, I learned to see past the following psychological tendencies.

Here's why you're getting the wrong answer, with examples

1. Availability Heuristic:

“The availability heuristic is a mental shortcut that relies on immediate examples that come to a given person's mind when evaluating a specific topic, concept, method, or decision. The availability heuristic operates on the notion that if something can be recalled, it must be important, or at least more important than alternative solutions which are not as readily recalled.” Students fall victim to this effect when they try to answer a question using their knowledge of a particular scientific concept instead of using the passage to deduce the correct answer. Many times, the answer to a question is constrained by terms offered by paragraphs, and as such, general scientific knowledge is not really applicable.

2. Choice-supportive Bias:

“choice-supportive bias is the tendency to retroactively ascribe positive attributes to an option one has selected.” This occurs when students look at the answer choices, decide that one answer feels right and try to justify it. This leads students to all sorts of outlandish justifications. One should avoid this by rigorously examining each answer choice regardless of how they “feel."

3. Outcome bias:

“The outcome bias is an error made in evaluating the quality of a decision when the outcome of that decision is already known.” This happens not during the MCAT test itself, but during the studying process when students feel that just because they got the right answer they did the question correctly. Since random guessing would lead a student to the correct answer ¼ of the time, it is essential that students examine both correct and incorrect answers during the study process in order to improve.

4. Serial Position effect:

"When asked to recall a list of items in any order (free recall), people tend to begin recall with the end of the list, recalling those items best (the recency effect).” This effect happens when a student doesn’t refer directly to the passage (typically during CARS) to answer the question but tries to answer the question based on their memory of the passage. In doing this, they will not equally weigh all the information in the passage and instead overemphasize an author's claims in the beginning and end of the passage, often leading to the selection of an incorrect answer choice.

5. Blind spot bias:

“The bias blind spot is the cognitive bias of recognizing the impact of biases on the judgment of others while failing to see the impact of biases on one's own judgment.” This applies to the CARS section when students fail to see their own bias in their appraisal of answer choices. Occasionally, the MCAT will feature a passage about an unpalatable topic such as corporal punishment or the death penalty, and the student will inadvertently substitute their own views for the authors’ views when answering the question. Recognizing that one’s own views differ from the authors and being aware of that can combat this.

6. Overconfidence:

“The overconfidence effect is a well-established bias in which a person's subjective confidence in his or her judgments is reliably greater than the objective accuracy of those judgments, especially when confidence is relatively high.” This can manifest in many ways on the MCAT, but I find it most prevalent with passages on the biological sciences when students feel very confident in the material and select their answer without doing a thorough appraisal of the answer choices compared to the conditions prescribed in the passage. For example, a student will confidently select an answer choice indicating that ATP is created in the Electron Transport Chain without comparing this information to the passage which says that the cell is in anaerobic conditions.

7. Selective perception:

“Selective perception is the tendency not to notice and more quickly forget stimuli that cause emotional discomfort and contradict our prior beliefs.” This tends to manifest in the level of care that students exhibit when trying to solve certain questions that they are weak at. For example, a student may struggle to read graphs, and when trying to answer a question, forget that the graph was even there, since they have such a bad reaction to graph questions. This type of mistake can be avoided by acknowledging one's weaknesses and owning the fact that simply because a question will be a struggle, does not mean it cannot be answered correctly. 

8. Conservatism bias:

When people cling to prior beliefs or evidence when presented with new evidence. This affects many students in the CARS section when an author presents one position before ultimately taking an opposing position. Students will often overweigh the author's first position compared to the second, simply because it came first despite stronger evidence that the author believes the second position. This weakness can be rectified by accurately mapping the passage so as to take the whole passage into account equally.

9. Salience effect:

This is when people focus on easily perceived aspects of a concept without taking into account their relative importance. This afflicts my students when they are examining multi-part answer choices where half an answer choice is easily appraisable and the other half is slightly trickier to examine, leading students to pick an answer solely based on part of an answer choice.

10. Stereotyping:

"A stereotype is a thought that can be adopted about specific types of individuals (things)…” This happens most often to students that try to group different types of questions that they seen have commonalities and try to answer them with the same strategy. While many similar questions can be answered with the same strategy, many students over-rely on such stereotypes and waste valuable time trying to adapt an incompatible method to question best attempted with a different strategy. This can be avoided by maintaining flexibility while answering questions, and not being afraid to start the process over. 

11. Ostrich Effect:

When people try to ignore or bypass situations they see as negative or risky. This happens often to students that see a very complex and detailed passage, assume the questions will be equally difficult, possibly time-consuming, and skip the passage, coming back to it later if they have time. In my experience, most super complex or difficult passages have somewhat easier questions, and skipping them leaves points on the table. Every student should try to answer every question.

12. Anchoring bias:

“is a cognitive bias that describes the common human tendency to rely too heavily on the first piece of information offered (the "anchor") when making decisions.” This is when students over-depend on the first time a particular topic was mentioned in the passage when answering a question as opposed to looking at how the topic was mentioned over the course of the passage.

13. Confirmation bias:

“This is the tendency to search for, interpret, favor, and recall information in a way that confirms one's preexisting beliefs or hypotheses, while giving disproportionately less consideration to alternative possibilities.” This leads students to recall information confirming that an answer choice is correct. This is problematic when one of the answer choices is more correct than the others but is presented later (as option C or D). Students often will pick an earlier answer choice with evidence behind it even without looking at the later answer choices, which often have more evidence behind them. This issue can be avoided by rigourously examining every answer choice every time.

Avoid these pitfalls!

How can you learn to fight these many potential pitfalls? I wouldn’t recommend trying to memorize them all in hopes of avoiding them. I recommend engaging in a tactic called Complete Justification, which you should check out in my next post!


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