Cognition in Major Depressive Disorder
Cognition in Major Depressive Disorder by: Roger S. McIntyre, Danielle S. Cha, and Joanna K. Soczynska
Review by: Jacqueline Veras & Danielle S. Cha
Cognition in Major Depressive Disorder is a concise pocketbook that provides its readers with an articulate description of cognition (e.g., concentration, learning, memory, etc.) and its impact on individuals diagnosed with major depressive disorder. Ample research has demonstrated that mood disorders can lead to and manifest cognitive impairments (e.g., inability to think, trouble with memory, and lack of concentration). However, there has been a paucity of research studies critically investigating the multifactorial effect impaired cognition has on individuals with major depressive disorder. These factors include, but are not limited to the individual’s social, work, or domestic circumstances. The enduring effects of cognitive dysfunction in major depressive disorder beyond resolution of the acute episode indicates that it may represent a trait/residual phenomenon in many individuals. The authors express the ignominious position of major depressive disorder as one of the world’s leading causes of disability and cognitive dysfunction as a principal cause of functional impairment.
Several significant points are posed in this pocketbook, bringing to light a perspective that encourages a greater focus on research and prospective treatment applications for a patient population characterized by cognitive impairments. Cognitive deficits are a focus of research for diverse patient populations– however, not all relate to mental illness – indicating that individuals may require different methods of treatment and care. In medicine, particularly psychiatry, patients’ treatments are applied across a heterogeneous group (e.g., major depressive disorder) without considering potential stratification strategies that may improve treatment outcomes (e.g., inflammation status, metabolic comorbidity, etc.). It remains to be determined whether cognitive dysfunction is subserved by discrete neurobiological substrate(s) and/or if they overlap with substrate(s) implicated in other neuropsychiatric disorders. Moreover, further investigation evaluating the contribution of various effector systems and molecular pathways that converge across frequently comorbid conditions (e.g., major depressive disorder, diabetes mellitus type II, and Alzheimer’s Disease) may provide the basis for novel treatment avenues specific to ameliorating and preventing cognitive dysfunction.
Depressive symptoms have consistently been associated with decreased workplace productivity. However, therapeutic interventions specifically targeting cognitive dysfunction in major depressive disorder are not currently available due to insufficient information on the underlying neurobiological substrate(s) and/or circuits associated with the effects of this subjective complaint. The hazards posed by cognitive impairments in major depressive disorder demonstrate the need to target cognition to better identify and treat, as well as prevent, reduce, and/or recover psychosocial function in individuals with major depressive disorder.
Available evidence provides the impetus to further refine potential mechanisms and molecular pathways subserving these disorders in order to more effectively treat these populations by aiming to reduce and prevent cognitive impairments. Several lines of evidence are brought forth in this pocketbook, encouraging novel treatment approaches and the pursuit of empirically-based, hypothesis-driven research. Questions regarding which treatment modalities, if any, are more effective in mitigating cognitive deficits, enhancing cognitive function, and/or preventing their occurrence in major depressive disorder remain unanswered. Cognition in Major Depressive Disorder uses available evidence to demonstrate the importance and need to explore the various facets of cognition and its subsequent deficits as a domain requiring further investigation in this heterogeneous clinical population. Collectively, this pocketbook effectively introduces the concept of cognition to its readers and its relevance to major depressive disorder. The chapters are constructed in such a way that the principal ideas are easily accessible at the start of each chapter in the form of two or three bullet points that is then elaborated throughout each chapter. The headers for each chapter, followed by the key points, research gathered, and analyses are all essential and successfully portrayed. The chapters demonstrate a wide variety of perspectives when discussing cognition and cognitive deficits in major depressive disorder, highlighting their mediational contribution to psychosocial impairment in this clinical population. The authors Dr. Roger S. McIntyre, Danielle S. Cha, and Joanna K. Soczynska exceeded expectations, providing an informative piece of work that represents a paramount exposition on the topic of cognition in major depressive disorder.