World's Best Scientists 2026 revealed!
Brian Hallahan

Brian Hallahan

D-Index & Metrics

Psychology

D-Index
33
Citations
4223
World Ranking
10598
National Ranking
35

Brian Hallahan publication distribution in Psychology in 2026

The chart shows the distribution of publications by all Research.com ranked scientists in the field of Psychology in 2026. The highlighted bar marks where Brian Hallahan sits on this spectrum.

31–40 publications: 6 scientists 41–50 publications: 52 scientists 51–60 publications: 138 scientists 61–70 publications: 299 scientists 71–80 publications: 461 scientists 81–90 publications: 605 scientists 91–100 publications: 713 scientists 101–110 publications: 736 scientists 111–120 publications: 686 scientists 121–130 publications: 670 scientists 131–140 publications: 644 scientists 141–150 publications: 597 scientists 151–160 publications: 576 scientists 161–170 publications: 477 scientists 171–180 publications: 450 scientists 181–190 publications: 397 scientists 191–200 publications: 343 scientists 201–210 publications: 328 scientists 211–220 publications: 313 scientists 221–230 publications: 283 scientists 231–240 publications: 226 scientists 241–250 publications: 196 scientists 251–260 publications: 201 scientists 261–270 publications: 171 scientists 271–280 publications: 151 scientists 281–290 publications: 139 scientists 291–300 publications: 113 scientists 301–310 publications: 102 scientists 311–320 publications: 100 scientists 321–330 publications: 76 scientists 331–340 publications: 92 scientists 341–350 publications: 85 scientists 351–360 publications: 69 scientists 361–370 publications: 71 scientists 371–380 publications: 63 scientists 381–390 publications: 58 scientists 391–400 publications: 57 scientists 401–410 publications: 43 scientists 411–420 publications: 33 scientists 421–430 publications: 50 scientists 431–440 publications: 41 scientists 441–450 publications: 32 scientists 451–460 publications: 27 scientists 461–470 publications: 28 scientists 471–480 publications: 25 scientists 481–490 publications: 28 scientists 491–500 publications: 20 scientists 501–510 publications: 23 scientists 511–520 publications: 26 scientists 521–530 publications: 17 scientists 531–540 publications: 21 scientists 541–550 publications: 14 scientists 551–560 publications: 16 scientists 561–570 publications: 10 scientists 571–580 publications: 22 scientists 581–590 publications: 9 scientists 591–600 publications: 14 scientists 601–610 publications: 9 scientists 611–620 publications: 11 scientists 621–630 publications: 4 scientists 631–640 publications: 7 scientists 641–650 publications: 5 scientists 651–660 publications: 10 scientists 661–670 publications: 8 scientists 671–680 publications: 8 scientists 681–690 publications: 4 scientists 691–700 publications: 3 scientists 701–704 publications: 4 scientists 705+ publications: 100 scientists
31 publications 705+

This scientist: 189 publications — 65th percentile

65% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 705 publications or more.

Brian Hallahan D-index placement in Psychology in 2026

The chart shows the D-index (discipline H-index) distribution of Psychology scientists ranked by Research.com in 2026. The highlighted bar marks where Brian Hallahan sits on this spectrum.

30–31 D-Index: 398 scientists 32–33 D-Index: 702 scientists 34–35 D-Index: 671 scientists 36–37 D-Index: 659 scientists 38–39 D-Index: 641 scientists 40–41 D-Index: 671 scientists 42–43 D-Index: 617 scientists 44–45 D-Index: 558 scientists 46–47 D-Index: 495 scientists 48–49 D-Index: 487 scientists 50–51 D-Index: 445 scientists 52–53 D-Index: 390 scientists 54–55 D-Index: 408 scientists 56–57 D-Index: 345 scientists 58–59 D-Index: 325 scientists 60–61 D-Index: 321 scientists 62–63 D-Index: 248 scientists 64–65 D-Index: 290 scientists 66–67 D-Index: 218 scientists 68–69 D-Index: 219 scientists 70–71 D-Index: 215 scientists 72–73 D-Index: 183 scientists 74–75 D-Index: 169 scientists 76–77 D-Index: 132 scientists 78–79 D-Index: 137 scientists 80–81 D-Index: 120 scientists 82–83 D-Index: 112 scientists 84–85 D-Index: 86 scientists 86–87 D-Index: 101 scientists 88–89 D-Index: 83 scientists 90–91 D-Index: 77 scientists 92–93 D-Index: 70 scientists 94–95 D-Index: 78 scientists 96–97 D-Index: 58 scientists 98–99 D-Index: 53 scientists 100–101 D-Index: 57 scientists 102–103 D-Index: 48 scientists 104–105 D-Index: 53 scientists 106–107 D-Index: 46 scientists 108–109 D-Index: 24 scientists 110–111 D-Index: 35 scientists 112–113 D-Index: 27 scientists 114–115 D-Index: 32 scientists 116–117 D-Index: 31 scientists 118–119 D-Index: 22 scientists 120–121 D-Index: 16 scientists 122–123 D-Index: 24 scientists 124–125 D-Index: 18 scientists 126–127 D-Index: 11 scientists 128–129 D-Index: 19 scientists 130–131 D-Index: 10 scientists 132–133 D-Index: 16 scientists 134–135 D-Index: 10 scientists 136–137 D-Index: 12 scientists 138–139 D-Index: 8 scientists 140–141 D-Index: 5 scientists 142–143 D-Index: 12 scientists 144+ D-Index: 98 scientists
30 D-Index 144+

This scientist: 33 D-Index — 10th percentile

10% of scientists in this discipline score the same or lower.

The last bar groups every scientist with 144 D-Index or more.

Overview

Brian Hallahan is affiliated with the National University of Ireland, Galway in Ireland. Their research spans multiple disciplines primarily within Medicine and Psychology, focusing extensively on Psychiatry and Mental Health, Clinical Psychology, Radiology, Nuclear Medicine and Imaging, Cognitive Neuroscience, and Biological Psychiatry.

Their main fields of study include:

  • Medicine
  • Psychology

The subfields that characterize their work are:

  • Psychiatry and Mental health
  • Clinical Psychology
  • Radiology, Nuclear Medicine and Imaging
  • Cognitive Neuroscience
  • Biological Psychiatry

Brian Hallahan's research topics cover:

  • Schizophrenia research and treatment
  • Functional Brain Connectivity Studies
  • Advanced Neuroimaging Techniques and Applications
  • Bipolar Disorder and Treatment
  • Tryptophan and brain disorders
  • COVID-19 and Mental Health
  • Mental Health Research Topics

Recent publications authored or co-authored by Brian Hallahan include:

  • In vivo hippocampal subfield volumes in bipolar disorder-A mega-analysis from The Enhancing Neuro Imaging Genetics through Meta-Analysis Bipolar Disorder Working Group, 2020, Human Brain Mapping
  • Impact of the COVID-19 pandemic on patients with pre-existing anxiety disorders attending secondary care, 2020, Irish Journal of Psychological Medicine
  • Early life Adversity, functional connectivity and cognitive performance in Schizophrenia: The mediating role of IL-6, 2021, Brain Behavior and Immunity
  • Childhood trauma, brain structure and emotion recognition in patients with schizophrenia and healthy participants, 2020, Social Cognitive and Affective Neuroscience
  • Changes in Default-Mode Network Associated With Childhood Trauma in Schizophrenia, 2021, Schizophrenia Bulletin

The most frequent venues of publication for Brian Hallahan's research are:

  • Irish Journal of Psychological Medicine
  • Biological Psychiatry
  • Schizophrenia Bulletin
  • European Neuropsychopharmacology
  • Brain Behavior and Immunity

Collaborations form an important part of Brian Hallahan's work. Frequent co-authors include:

  • Colm McDonald
  • Dara M. Cannon
  • Laurena Holleran
  • Gary Donohoe
  • Derek W. Morris

Best Publications

  • Structural magnetic resonance imaging in bipolar disorder: an international collaborative mega-analysis of individual adult patient data.

    Brian Hallahan;John Newell;Jair C. Soares;Paolo Brambilla;Paolo Brambilla

  • Efficacy of omega-3 highly unsaturated fatty acids in the treatment of depression.

    Brian Hallahan;Timothy Ryan;Joseph R. Hibbeln;Ivan T. Murray

  • Omega-3 fatty acid supplementation in patients with recurrent self-harm. Single-centre double-blind randomised controlled trial.

    Brian Hallahan;Joseph R Hibbeln;John M Davis;Malcolm R Garland

  • Clinical and anatomical heterogeneity in autistic spectrum disorder: a structural MRI study

    Fiona Toal;Eileen Daly;Lisa Page;Quinton Deeley

  • Fragile X-associated disorders: a clinical overview

    Anne Gallagher;Brian Hallahan;Brian Hallahan

  • Essential fatty acids and mental health

    Brian Hallahan;Malcolm R Garland

  • Neuropsychiatric syndromes of multiple sclerosis

    Ruth Murphy;Stefani O'Donoghue;Timothy Counihan;Colm McDonald

  • Women with autistic-spectrum disorder: magnetic resonance imaging study of brain anatomy

    Michael C. Craig;Shahid H. Zaman;Eileen M. Daly;William J. Cutter

  • Brain morphometry volume in autistic spectrum disorder: a magnetic resonance imaging study of adults.

    B. Hallahan;E. M. Daly;Grainne McAlonan;E. Loth

  • In vivo brain anatomy of adult males with Fragile X syndrome: an MRI study.

    Brian P. Hallahan;Brian P. Hallahan;Brian P. Hallahan;Michael C. Craig;Fiona Toal;Eileen M. Daly

  • Response inhibition and serotonin in autism: a functional MRI study using acute tryptophan depletion

    Eileen Daly;Christine Ecker;Brian Hallahan;Quinton Deeley

  • Lipids and essential fatty acids in patients presenting with self-harm

    Malcolm R Garland;Brian Hallahan;Mairead McNamara;Philip A Carney

  • Childhood trauma levels in individuals attending adult mental health services: An evaluation of clinical records and structured measurement of childhood trauma

    Amy Rossiter;Fintan Byrne;Anna Paulina Wota;Zafar Nisar

  • Anatomy and aging of the amygdala and hippocampus in autism spectrum disorder: an in vivo magnetic resonance imaging study of Asperger syndrome.

    Clodagh Murphy;Quinton Deeley;Eileen Daly;Christine Ecker

  • Serotonin and the neural processing of facial emotions in adults with autism: an fMRI study using acute tryptophan depletion.

    Eileen M Daly;Quinton Deeley;Christine Ecker;Michael Craig

  • Towards Precision Medicine in Psychosis: Benefits and Challenges of Multimodal Multicenter Studies-PSYSCAN: Translating Neuroimaging Findings From Research into Clinical Practice.

    Stefania Tognin;Hendrika H van Hell;Kate Merritt;Inge Winter-van Rossum

  • In vivo hippocampal subfield volumes in bipolar disorder-A mega-analysis from The Enhancing Neuro Imaging Genetics through Meta-Analysis Bipolar Disorder Working Group.

    Unn Kristin H. Haukvik;Unn Kristin H. Haukvik;Tiril Pedersen Gurholt;Tiril Pedersen Gurholt;Stener Nerland;Torbjørn Elvsåshagen;Torbjørn Elvsåshagen

  • Essential fatty acids and their role in the treatment of impulsivity disorders

    Brian Hallahan;Malcolm R. Garland;Malcolm R. Garland

  • Changes in male brain responses to emotional faces from adolescence to middle age

    Quinton Deeley;Eileen M. Daly;Rayna Azuma;Simon A. Surguladze

  • Progressive Brain Atrophy and Cortical Thinning in Schizophrenia after Commencing Clozapine Treatment

    Mohamed Ahmed;Dara M Cannon;Cathy Scanlon;Laurena Holleran

  • Structural Magnetic Resonance Imaging in Bipolar Disorder: An International Collaborative Mega-Analysis of Individual Adult Patient Data

    Brian Hallahan;John Newell;Jair C. Soares;Paolo Brambilla

Frequent Co-Authors

Colm McDonald
Colm McDonald University of Galway
Dara M. Cannon
Dara M. Cannon University of Galway
Eileen Daly
Eileen Daly King's College London
Declan G. Murphy
Declan G. Murphy King's College London
Gary Donohoe
Gary Donohoe University of Galway
Aiden Corvin
Aiden Corvin Trinity College Dublin
Derek W. Morris
Derek W. Morris University of Galway
Agnes Higgins
Agnes Higgins Trinity College Dublin
Michael C. Craig
Michael C. Craig King's College London
Quinton Deeley
Quinton Deeley King's College London

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