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A Deep Dive into Psychological Disorders

In the MCAT section of Psychological, Social, and Biological Foundations of Behavior, there is a section dedicated to testing the aspiring medical student’s knowledge concerning psychological disorders. This article would tackle some questions that may aid you in understanding the topic more and prepare you for your upcoming exam! It must be noted that this does not cover the entirety of the topic and there are still other types of psychological disorders (and nervous system disorders) that are not discussed in this article.

1. What are the three clusters of personality disorders?

Since there are numerous types and intensities of unusual behavior patterns, a system was developed to compile and differentiate the various forms of personality disorders.

Cluster A: Strange and Eccentric Behaviors

  1. Schizotypal Personality Disorder: thoughts and actions that are deemed to be abnormal according to societal and cultural norms

  2. Schizoid Personality Disorder: detachment and lack of interest in interpersonal relationships and social situations

  3. Paranoid Personality Disorder: strong suspicion and distrust of others

Cluster B: Excessively Dramatic and Emotional Behaviors

  1. Narcissistic Personality Disorder: attention-seeking attitudes and the strong belief that one is better in aspects like physical attractiveness and achievements than others

  2. Antisocial Personality Disorder: disregard for safety, well-being, and feelings of others as well as lack of remorse for irresponsible and immoral behaviors

  3. Borderline Personality Disorder: unstable moods, self-image, and relationships

  4. Histrionic Personality Disorder: excessive and over-dramatic actions to garner attention

Cluster C: Distressed and Frightened Behaviors

  1. Obsessive-Compulsive Disorder: extreme attention to cleanliness, orderliness, and perfectionism as well as the desire to be in control of specific items and situations

  2. Dependent Personality Disorder: excessive dependence on others, inability to act for oneself, and need for constant reassurance

  3. Avoidant Personality Disorder: high sensitivity and fear of failure, rejection, and embarrassment

2. What are the positive and negative symptoms of schizophrenia?

Positive symptoms are thoughts, attitudes, and behaviors that stray away from social norms. Auditory and/or visual hallucinations wherein the individual could see events that are not happening in real life. Moreover, delusions entail erroneous and unusual beliefs that the individual holds with strong conviction. In addition, an individual suffering from schizophrenia may have difficulties in regulating one’s line of thoughts and conversing in a coherent manner.

Negative symptoms, on the other hand, refer to aspects that are absent from the usual behavior. This includes a lack of interest, emotion, concentration, and social interactions.

3. What is the monoamine theory of depression?

The monoamine theory of depression discusses how the aforementioned illness is said to be caused by decreased or depleted levels of neurotransmitters, specifically serotonin, norepinephrine, and dopamine in the central nervous system. This can lead to drastic changes in appetite, mood, and sleeping habits as well as frequent occurrences of suicidal thoughts.

4. What are the three forms of bipolar disorders that medical professionals can select from when making an accurate diagnosis?

Firstly, Bipolar I disorder involves manic episodes that last at least seven days or that have a severity required for immediate hospitalization. These may or may not require depressive episodes. Bipolar II disorder refers to both manic and depressive episodes. There must be at least one major depressive episode that occurs before or after a hypomanic episode. Cyclothymia, which is said to have less severe symptoms compared to the previous two forms, entails periods of hypomania and depression that last for a minimum of two years.

Note: Although Alzheimer’s Disease and Parkinson’s Disease are not psychological disorders, this MCAT portion has been known to include these nervous system disorders in the examination. Therefore, it would be beneficial to review details about such!

5. What are the symptoms of Alzheimer’s Disease?

Aside from memory loss and changes in personality, Alzheimer’s Disease causes beta-amyloid plaques which are created from the breakdown of larger protein molecules. Then, the accumulation of beta-amyloid protein pieces would disrupt and impair cell-to-cell signaling and cell function.

Moreover, there would be the occurrence of neurofibrillary tangles of tau protein which starts from unusually high levels of aggregated protein present in the brain. There would be the detachment of tau proteins from the microtubules and the attachment of such to other tau molecules. This would produce threads and subsequent entanglements within the neurons that would cause blockages in the communication and transport systems.

Furthermore, Alzheimer’s Disease brings forth atrophy which is the progressive deterioration of neurons and nerve tissues.

6. What can be used to treat or alleviate Parkinson’s Disease?

Levodopa or L-DOPA, which is a precursor to dopamine, has been utilized to manage Parkinson’s Disease because it has the ability to replace the lost dopamine in the brain. This increases the production of the neurotransmitter which improves the motor function of the affected individual.

In addition, a new approach has been created to control the symptoms of Parkinson’s Disease. It was discovered that through stem cell therapy, there may be the regeneration and repair of dopaminergic neurons in the brain.

I hope that this article helped you in your MCAT preparation! Studying psychological disorders is definitely essential in the medical field because medical professionals would have to be equipped with the knowledge and skills on forming accurate diagnoses according to the symptoms that the patients present. They must carefully study the patients’ mental processes and behavioral patterns as well as employ the proper treatment strategies. It is all about providing care for the overall health and well-being of the patients.

Good luck, future medical professional!

Oriana Tolentino



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