Which type of disorder involves an inflexible pattern of relating and thinking that causes distress?

The type of disorder that involves an inflexible pattern of relating and thinking, which can lead to significant distress, is the personality disorder. These disorders are characterized by enduring patterns of behavior, cognition, and inner experience that deviate markedly from the expectations of an individual's culture. This can manifest in various ways, such as difficulties in interpersonal relationships, challenges in managing emotions, and rigid ways of thinking that do not adapt well to different situations. Consequently, individuals with personality disorders may find it hard to function effectively in different aspects of life, causing distress not only to themselves but also to those around them.

On the other hand, anxiety disorders primarily involve excessive fear or anxiety related to specific situations or objects but don’t inherently include the rigid patterns of behavior found in personality disorders. Behavioral disorders typically focus on specific patterns of behavior that can be changed or managed, rather than the deeply ingrained personality elements. Adjustment disorders are short-term responses to stressors, lacking the pervasive patterns seen in personality disorders. Thus, personality disorders are distinct in their enduring nature and the inflexible patterns of thinking and behavior that lead to distress in interpersonal interactions and overall functioning.