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Abstract
Background. Thought disorders are among the key psychopathological phenomena and play an important role in the early diagnosis, differential diagnosis, and assessment of the course of mental disorders. Although numerous studies have investigated their phenomenology, neurobiological mechanisms, and clinical manifestations, contemporary approaches to the systematic identification of thought disorders during the clinical interview, particularly in clinical psychology, remain insufficiently integrated.
Objective. To summarise current scientific evidence on thought disorders, describe their neurobiological and psychopathological characteristics, analyse contemporary approaches to their assessment during the clinical interview, and propose a structured algorithm for the assessment of thought processes in clinical practice.
Materials and methods. A narrative review of contemporary scientific literature was conducted using publications indexed in international databases, clinical practice guidelines, international diagnostic classifications, and psychometric studies. Bibliographic, comparative, system-structural, and clinical-psychopathological methods were applied to analyse and synthesise the available evidence.
Results. Current concepts describe thought disorders as multidimensional psychopathological phenomena associated with dysfunction of language, executive, and cognitive neural networks. Contemporary evidence indicates that thought disorders have a transdiagnostic nature and may occur in schizophrenia, bipolar disorder, depressive disorders, neurocognitive disorders, organic brain diseases, traumatic brain injury, and autism spectrum disorders. The main characteristics of thought processes, including tempo, sequence, goal-directedness, logical organisation, productivity, and critical thinking, were systematised, and their clinical significance as well as contemporary approaches to their assessment during the mental status examination were analysed. Modern standardised assessment instruments, including the Thought, Language and Communication Scale (TLC), the Thought and Language Disorder Scale (TALD), the Thought and Language Index (TLI), and the Clinical Language Disorder Rating Scale (CLANG), were reviewed. A structured algorithm for the clinical interview aimed at comprehensively assessing thought disorders was proposed.
Conclusions. Comprehensive assessment of thought disorders during the clinical interview improves the quality of psychopathological evaluation, facilitates early detection of mental disorders, and enhances differential diagnosis. The proposed algorithm may be used by clinical psychologists, psychiatrists, psychiatry residents, and multidisciplinary mental health teams, as well as in undergraduate and postgraduate education in mental health.
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Copyright (c) 2026 Ольга Люта, Олена Венгер, Юрій Мисула, Неоніла Корильчук, Юлія Венгер