A patient is described as being detached from social relationships and showing restricted emotional responses. Which personality disorder is this?

The personality disorder characterized by a detachment from social relationships and restricted emotional responses is the schizoid personality disorder. Individuals with this condition typically exhibit a pervasive pattern of indifference to social relationships, combined with a limited range of emotional expression in interpersonal settings. They may appear aloof or isolated, often preferring solitary activities and showing little desire for intimacy or closeness with others. Their emotional world is often muted, leading to perceptions of being cold or indifferent, which aligns with the key traits of this disorder.

In contrast, the other personality disorders mentioned present with different patterns of behavior and emotional responses. Borderline personality disorder often involves intense and unstable interpersonal relationships, along with marked emotional fluctuations. Paranoid personality disorder is characterized by a pervasive distrust and suspicion of others, leading to significant interpersonal difficulties. Histrionic personality disorder focuses on excessive emotionality and attention-seeking behavior, which is distinctly different from the emotional detachment seen in schizoid personality disorder. Thus, the description provided in the question aligns most closely with schizoid personality disorder.