Examining Identification Through the Study of Responses to Traumatic Events Reveals a Fundamental Process: Thinking by Similarity

Objective: Identification—the experience of perceiving oneself as like another—is a central process in human relatedness, empathy, and emotion regulation. Although well-established in psychoanalytic and developmental theory, its function under stress and trauma has received limited systematic attention. This paper integrates interpersonal, cognitive, and neurobiological perspectives to conceptualize identification as a core mental operation and to propose thinking by similarity as its underlying cognitive process. Method: Through focused conceptual synthesis, the manuscript draws on psychoanalytic, developmental, social-cognitive, and neurobiological research to examine the origins, mechanisms, and manifestations of identification across the life span and following high-stress and traumatic events. Results: Identification emerges early in development through attachment and imitation, shaping empathy and social understanding. Neurobiological evidence, including mirror neurons and limbic system activation, demonstrates shared brain activations that ground identification biologically. Under threat or trauma, cognition may shift to thinking by similarity, facilitating appraisal of safety and danger but also increasing vulnerability to distress and cognitive rigidity. Following traumatic events, this process may yield adaptive empathy and solidarity or maladaptive over-identification with victims and aggressors and posttraumatic stress disorder. Conclusions: Identification is a fundamental psychological and neurobiological process. The concept of identification as thinking by similarity offers a unifying linking of psychodynamic, developmental, and neurobiological models. This framework advances understanding of empathy, resilience, and vulnerability under stress, with implications for trauma-informed clinical practice and research.