Clusters, Dimensions, and Hierarchies: Finding a Path Forward for the Neuroscience of Mental Disorders?

The Diagnostic and Statistical Manual of Mental Disorders (DSM) serves as the primary classification system for mental health disorders, providing standardized diagnostic criteria for clinicians and researchers. First published by the American Psychiatric Association (APA) in 1952, the DSM has undergone several revisions to reflect evolving psychiatric understanding. The fifth edition, DSM-5, released in 2013, introduced key updates that expanded diagnostic categories and modified diagnostic...

Consider the gas molecules in a cylinder. They move in a random motion as they collide with each other and change speed and direction. The average of all the path lengths between collisions is known as the "mean free path."

Abraham Maslow's theory of motivation, introduced in 1943, is widely known as the "Hierarchy of Needs." This theory posits that human needs are arranged in a hierarchical structure, starting with basic survival needs and progressing toward more complex psychological and self-fulfillment desires. The hierarchy is typically a pyramid, and the lower needs must be satisfied to reach the next level.
At the pyramid's base are physiological needs, including food, water, and shelter...

The hierarchy of motor control refers to the different levels of organization and processing involved in controlling movement in the body. These levels range from higher cortical areas involved in planning and decision-making to lower spinal cord reflexes that respond automatically to external stimuli.

Consider the two thermodynamic processes involving an ideal gas that are represented by paths AC and ABC in Figure 1:

Intrinsically disordered proteins are a group of proteins that do not fold into specific three-dimensional structures. Their structural flexibility allows them to complement ordered proteins to perform functions that are inaccessible to rigid structures. They are more common in eukaryotes than prokaryotes and may either be exclusively intrinsically disordered or hybrid proteins, consisting of a mix of ordered and disordered regions. The absence of a rigid structure in these proteins can be...