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Psychology

D-Index
48
Citations
8985
World Ranking
5946
National Ranking
40

Overview

Tor K. Larsen is affiliated with the University of Bergen in Norway and has an extensive body of research primarily within medicine and neuroscience. The scientist's work largely focuses on psychiatry and mental health, clinical psychology, cellular and molecular neuroscience, biological psychiatry, and philosophy as subfields of study.

The central themes in Larsen's research involve schizophrenia research and treatment, bipolar disorder and treatment, tryptophan and brain disorders, mental health and psychiatry, treatment of major depression, neurotransmitter receptor influence on behavior, and stress responses and cortisol.

The scientist's recent publications include several articles across prominent journals. Notable papers are:

  • Amisulpride, aripiprazole, and olanzapine in patients with schizophrenia-spectrum disorders (BeSt InTro): a pragmatic, rater-blind, semi-randomised trial, 2020, The Lancet Psychiatry
  • Sex differences in antipsychotic efficacy and side effects in schizophrenia spectrum disorder: results from the BeSt InTro study, 2021, Schizophrenia
  • Association between early suicidal trajectories in first-episode psychosis and 10-year follow-up: TIPS registry-linked study, 2023, The Lancet Psychiatry
  • One-Year Outcome and Adherence to Pharmacological Guidelines in First-Episode Schizophrenia, 2020, Journal of Clinical Psychopharmacology
  • The association between cytokines and psychomotor speed in a spectrum of psychotic disorders: A longitudinal study, 2021, Brain Behavior & Immunity - Health

Frequent collaborators in Larsen's work include:

  • Erik Johnsen
  • Rune A. Kroken
  • Maria A. Rettenbacher
  • Solveig Klæbo Reitan
  • Inge Joa

Larsen's research outputs have been published repeatedly in key venues such as:

  • Schizophrenia Research
  • Journal of Clinical Psychopharmacology
  • The Lancet Psychiatry
  • Schizophrenia
  • Brain Behavior & Immunity - Health

The scientist contributes extensively to understanding complex psychiatric disorders, especially focusing on schizophrenia and bipolar disorder treatments. The research also investigates biological underpinnings such as cytokine associations and the impact of neurotransmitter receptors on behavior, with longitudinal and clinical trial approaches frequently employed.

Best Publications

  • Reducing the duration of untreated first-episode psychosis: effects on clinical presentation.

    Ingrid Melle;Tor K. Larsen;Ulrik Haahr;Svein Friis

  • First-episode Schizophrenia: I. Early Course Parameters

    Tor K. Larsen;Thomas H. McGlashan;Lars Conrad Moe

  • Long-term follow-up of the TIPS early detection in psychosis study: effects on 10-year outcome.

    Wenche ten Velden Hegelstad;Tor K. Larsen;Bjørn Auestad;Julie Evensen

  • Early detection strategies for untreated first-episode psychosis

    Jan Olav Johannessen;Thomas H McGlashan;Tor Ketil Larsen;Marthe Horneland

  • Early detection and intervention in first-episode schizophrenia: a critical review

    T. K. Larsen;S. Friis;U. Haahr;I. Joa

  • First-episode schizophrenia with long duration of untreated psychosis: Pathways to care

    Tor K. Larsen;Jan Olav Johannessen;Stein Opjordsmoen

  • Early Detection of the First Episode of Schizophrenia and Suicidal Behavior

    Ingrid Melle;Jan Olav Johannesen;Svein Friis;Ulrik Haahr

  • The Key to Reducing Duration of Untreated First Psychosis: Information Campaigns

    Inge Joa;Jan Olav Johannessen;Bjørn Auestad;Svein Friis

  • Premorbid functioning versus duration of untreated psychosis in 1 year outcome in first-episode psychosis.

    Tor K. Larsen;Lars C. Moe;Lars Vibe-Hansen;Jan Olav Johannessen

  • Neurocognitive Dysfunction in First-Episode Psychosis: Correlates With Symptoms, Premorbid Adjustment, and Duration of Untreated Psychosis

    Bjørn Rishovd Rund;Ingrid Melle;Svein Friis;Tor K. Larsen

  • Prevention of negative symptom psychopathologies in first-episode schizophrenia: two-year effects of reducing the duration of untreated psychosis.

    Ingrid Melle;Tor K. Larsen;Ulrik Haahr;Svein Friis

  • Shortened Duration of Untreated First Episode of Psychosis: Changes in Patient Characteristics at Treatment

    Tor K. Larsen;Thomas H. McGlashan;Jan Olav Johannessen;Svein Friis

  • First-episode Schizophrenia: II. Premorbid Patterns by Gender

    Tor K. Larsen;Thomas H. McGlashan;Jan Olav Johannessen;Lars Vibe-Hansen

  • Early detection of psychosis: positive effects on 5-year outcome.

    T. K. Larsen;I. Melle;B. Auestad;U. Haahr

  • The course of neurocognitive functioning in first-episode psychosis and its relation to premorbid adjustment, duration of untreated psychosis, and relapse

    Bjørn Rishovd Rund;Ingrid Melle;Svein Friis;Jan Olav Johannessen

  • Premorbid adjustment in first-episode non-affective psychosis: distinct patterns of pre-onset course.

    Tor K. Larsen;Svein Friis;Ulrik Haahr;Jan Olav Johannessen

  • Early Detection of First-Episode Psychosis: The Effect on 1-Year Outcome

    Tor K. Larsen;Ingrid Melle;Bjørn Auestad;Svein Friis

  • Neurocognition and Duration of Psychosis: A 10-year Follow-up of First-Episode Patients

    Bjørn Rishovd Rund;Bjørn Rishovd Rund;Helene Eidsmo Barder;Julie Evensen;Julie Evensen;Ulrik Haahr;Ulrik Haahr

  • Predictors of involuntary hospitalizations to acute psychiatry

    Kjetil Hustoft;Tor Ketil Larsen;Bjørn Auestad;Inge Joa

  • Substance abuse in first-episode non-affective psychosis

    Tor K. Larsen;Ingrid Melle;Bjørn Auestad;Svein Friis

Frequent Co-Authors

Ingrid Melle
Ingrid Melle University of Oslo
Inge Joa
Inge Joa Stavanger University Hospital
Bjørn Rishovd Rund
Bjørn Rishovd Rund Vestre Viken Hospital Trust
Erik Simonsen
Erik Simonsen University of Copenhagen
Per Vaglum
Per Vaglum University of Oslo
Kjetil Sundet
Kjetil Sundet University of Oslo
Larry Davidson
Larry Davidson Yale University
Kenneth Hugdahl
Kenneth Hugdahl University of Bergen
Erik Lykke Mortensen
Erik Lykke Mortensen University of Copenhagen
Srdjan Djurovic
Srdjan Djurovic Oslo University Hospital

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