ARTICLE REVIEW2Intelligence is defined by two categories, fluid and crystallized intelligence. An individual’s fluid intelligence is their global capacity to reason and logic. Fluid intelligence is theworking memory which provides the ability to learn new things, think abstractly and quickly to accomplish basic and sometimes complex problem solving. (Gazzaniga, Ivry & Mangun, 2013). Cognitive domains are the mental abilities to process information. These necessary processes allow individuals to perform task and function successfully. Impairments in these executive functions greatly affect the fluid intelligence and vice versa. In this paper I will review the article, The Relationship Between Executive Functions and Fluid Intelligence in Parkinson’s Disease(Roca et al., 2012), in attempts to address the major findings within the study and explain the strengths and weaknesses. Major Findings/ConclusionsWithin this article, The Relationship Between Executive Functions and Fluid Intelligence in Parkinson’s Disease, (Roca et al., 2012), researchers demonstrated the degeneration of fluid intelligence is a consequential contributor to frontal deficits in Parkinson’s disease. Research in this study showed that with some classical ‘executive function’ tasks, frontal deficiencies were solely elucidated by fluid intelligence. Whereas secondary test of frontal functions, which were statistically controlled, showed the frontal deficits remained after the conclusion of the test. A frontal deterioration in functions, is frequently the most observed cognitive decline detected in Parkinson’s Disease. This specific study is steered to resolve the execution of fluid intelligence insuch deteriorations. Researchers concluded these findings proved that it is necessary to test fluid intelligence in Parkinson’s patients using definitive task focusing on both theory of mind and multi-tasking (Roca et al., 2012).