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Lena Palaniyappan

10 papers in the library · 53 citations · publishing 2019-2026

Papers

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Reading between the lines: Combining pause dynamics and semantic coherence for automated assessment of thought disorder.

Neuropsychologia July 28, 2026 Feng Chen, Weizhe Xu, Changye Li et al.

Formal thought disorder (FTD), a hallmark of schizophrenia spectrum disorders, manifests as incoherent speech and poses challenges for clinical assessment. Traditional clinical rating scales, though validated, are resource-intensive and lack scalability. Automated speech recognition (ASR) allows for objective quantification of linguistic and temporal features of speech, offering scalable...

Operationalizing the Whole of Psychic Life: Toward a Structured Framework for Psychopathology.

Psychopathology June 15, 2026 Ary Gadelha, Bernardo Haguiara, Pedro Gabriel Lorencetti et al.

Contemporary psychiatry has advanced by decomposing behavior into discrete constructs, improving reliability but fragmenting conceptual foundations. Excessive comorbidity, blurred diagnostic boundaries, and the reification of operational criteria have created a gap between empirical data and the understanding of mental life as a coherent, lived whole - the modern paradox of "more data, less...

Grounding psychosis research: why observable signs should anchor biological investigations.

Frontiers in Psychiatry 2026 Lena Palaniyappan

Biological psychiatry faces a significant epistemic challenge in identifying valid objects for mechanistic research. Both diagnostic constructs and individual symptoms are abstract symbols defined circularly within a closed hermeneutic system, creating a symbol grounding problem that hinders the discovery of biophysical substrates (biomarkers). I argue that progress requires an epistemological...

Quantitative natural language processing markers of psychoactive drug effects: A pre-registered systematic review

Journal of Psychopharmacology February 16, 2025 Sachin Ahuja, Farida Zaher, Lena Palaniyappan 4 citations

Psychoactive substances used for recreational purposes have mind-altering effects, but systematic evaluation of these effects is largely limited to self-reports. Automated analysis of expressed language (speech and written text) using natural language processing (NLP) tools can provide objective readouts of mental states. In this pre-registered systematic review, we investigate findings from...

Syntactic complexity of spoken language in the diagnosis of schizophrenia: A probabilistic Bayes network model.

Schizophrenia Research September 1, 2023 Angelica M Silva, Roberto Limongi, Michael Mackinley et al. 49 citations

In the clinical linguistics of schizophrenia, syntactic complexity has received much attention. In this study, we address whether syntactic complexity deteriorates within the six months following the first episode of psychosis in those who develop a diagnosis of schizophrenia. We collected data from a cohort of twenty-six first-episode psychosis and 12 healthy control subjects using the Thought...

Language and Psychosis: Tightening the Association.

Schizophrenia Bulletin March 22, 2023 Eric J Tan, Iris E C Sommer, Lena Palaniyappan

This special issue of DISCOURSE in Psychosis focuses on the role of language in psychosis, including the relationships between formal thought disorder and conceptual disorganization, with speech and language markers and the neural mechanisms underlying these features in psychosis. It also covers the application of computational techniques in the study of language in psychosis, as well as the...

Neuroimaging the Consciousness of Self: Review, and Conceptual-Methodological Framework.

Neuroscience and Biobehavioral Reviews January 26, 2020 Paul Frewen, M. Schroeter, Giuseppe Riva et al.

We review neuroimaging research investigating self-referential processing (SRP), that is, how we respond to stimuli that reference ourselves, prefaced by a lexical-thematic analysis of words indicative of "self-feelings". We consider SRP as occurring verbally (V-SRP) and non-verbally (NV-SRP), both in the controlled, "top-down" form of introspective and interoceptive tasks, respectively, as...

Glutamate and Dysconnection in the Salience Network: Neurochemical, Effective-connectivity, and Computational Evidence in Schizophrenia

bioRxiv November 2, 2019 Roberto Limongi, P. Jeon, Michael Mackinley et al. preprint

In the dysconnection hypothesis, psychosis is caused by NMDA hypofunction resulting in aberrant network connectivity. Combining a cognitive-control task, functional magnetic resonance spectroscopy, and functional magnetic resonance imaging, we tested this hypothesis in the salience network of 20 first-episode psychosis (FEP) and 20 healthy control (HC) subjects. Across groups, glutamate...

Dysregulated Brain Dynamics in a Triple-Network Saliency Model of Schizophrenia and Its Relation to Psychosis.

Biological Psychiatry 2019 Kaustubh Supekar, Weidong Cai, R. Krishnadas et al.

BACKGROUND Schizophrenia is a highly disabling psychiatric disorder characterized by a range of positive "psychosis" symptoms. However, the neurobiology of psychosis and associated systems-level disruptions in the brain remain poorly understood. Here, we test an aberrant saliency model of psychosis, which posits that dysregulated dynamic cross-network interactions among the salience network...