Dr O’Sullivan completed a PhD in clinical neurology in 2010 from University College London. He has published approximately 130 peer-reviewed papers in high quality medical journals, and is the author of four book chapters. He is also the author of 6 papers reviewed by the Faculty of 1000, a post-publication peer review website.

His areas of publication are from across the spectrum of neurological disorders including Parkinson’s Disease, Movement Disorders, Epilepsy, Multiple Sclerosis, Stroke, Headache, Neuromuscular Disorders, Peripheral Neuropathy, Spinal Cord diseases, Neuro-genetics, Neuro-Infectious Disease, Neuropathic pain, Autonomic disorders, Sleep disorders, Behavioural Neurology, Neuro-ophthalmology, Neuro-oncology, Neuro-Urology and Dementia.

Follow his Research publication list to see more.

Dr. O’Sullivan is a Clinical Senior Lecturer at University College Cork (UCC). He has on-going research studies in the fields of Movement Disorders, Headache and is the co-founder of the UCC Parkinson’s Disease Research Cluster. http://www.ucc.ie/en/pdrc/


Peer-reviewed Publications

Management of Impulse Control and Related Disorders in Parkinson’s Disease: An Expert Consensus.
Debove I, Paschen S, Amstutz D, Cardoso F, Corvol JC, Fung VSC, Lang AE, Martinez
Martin P, Rodríguez-Oroz MC, Weintraub D, Krack P, Deuschl G; and the Members of
the ICBD in PD Management Consensus Group. Mov Disord. 2024 Feb;39(2):235-
248. doi: 10.1002/mds.29700. Epub 2024 Jan 17.PMID: 38234035  Review.

Predictors of Motor Symptom Response with Levodopa-Carbidopa Intestinal Gel in Advanced PD: COSMOS Post Hoc Analysis
Fasano A, O’Sullivan S, Johansson A, Parra J, Saad A, Bergmann L, Krikmann U, Simu
M
Eur J Neurol 2022 29, 175-175
Neuropsychiatric Features of Punding and Hobbyism in Parkinson’s Disease.
Barbosa P, O’Sullivan SS. , Joyce E, Lees AJ, Warner TT, Djamshidian A. Mov Disord Clin
Pract. 2021 Nov 11;9(1):82-86. doi: 10.1002/mdc3.13363


A subtle presentation of a treatable cause of predominant hemidystonia with minimal
ataxia.
Wrigley SM, O’Sullivan SS. , Ryan AM. Parkinsonism Relat Disord. 2021 Nov 19:S1353-
8020(21)00397-7. doi: 10.1016/j.parkreldis.2021.11.001

Neurology patient engagement with online health-related resources.
Murphy OC, Suhaimi SS, O’Sullivan SS. J Neurol Sci. 2021 Jan 15;420:117264. doi: 10.1016/j.jns.2020.117264. Epub 2020 Dec 9. PMID: 33341083

The “round the houses” sign and “zig-zag” sign in progressive supranuclear palsy and other conditions.
Fearon C, Field R, Donlon E, Murphy OC, Cronin S, Buckley C, Williams L, Llamas Y, O’Dowd S, O’Sullivan SS, Gold DR, Gold DR, Walsh R, Healy DG, Quinn N, Lynch T. Parkinsonism Relat Disord. 2020 Dec;81:94-95. doi: 10.1016/j.parkreldis.2020.10.030. Epub 2020 Oct 19.PMID: 33120075

Scales to assess impulsive and compulsive behaviors in Parkinson’s disease: Critique and recommendations.
Evans AH, Okai D, Weintraub D, Lim SY, O’Sullivan SS, Voon V, Krack P, Sampaio C, Post B, Leentjens AFG, Martinez-Martin P, Stebbins GT, Goetz CG, Schrag A; Members of the International Parkinson and Movement Disorder Society (IPMDS) Rating Scales Review Committee.
Mov Disord. 2019 May 28. doi: 10.1002/mds.27689. [Epub ahead of print] PMID: 31136681

The long-term outcome of impulsive compulsive behaviours in Parkinson’s disease.
Barbosa PM, Djamshidian A, O’Sullivan SS, de Pablo-Fernandez E, Korlipara P, Morris HR, Bhatia KP, Limousin P, Foltynie T, Lees AJ, Warner TT.
J Neurol Neurosurg Psychiatry. 2019 Feb 1. doi: 10.1136/jnnp-2018-319891. [Epub ahead of print]  PMID: 30709896

The utility of dopamine transporter scans for diagnosing Parkinsonian disorders
Crotty GF, O’Corragain OA, Bogue C, Crotty J, O’Sullivan SS.
Ir Med J. 2018 May 10;111(5):751.

PMID: 30489047

Compulsive sexual behaviour in Parkinson’s disease is associated with higher doses of levodopa.
Barbosa PM, Grippe T, Lees AJ, O’Sullivan S, Djamshidian A, Warner TT.
J Neurol Neurosurg Psychiatry. 2018 Oct;89(10):1121-1123. doi: 10.1136/jnnp-2017-317298.

Teenage Onset Head Tremor Due to Novel Mutation in GNAL Gene
O’Connor A, M Buckley M, O’Sullivan SS
Movement Disorders Clinical Practice 2017 4 (6), 903-904

The readability of internet information on lewy body dementia
O’connor A, Crowley F, Vaughan D, O’Sullivan SS
J Neurol Neurosurg Psychiatry 88 (Suppl 1), A21-A21

Excessive burden of lysosomal storage disorder gene variants in Parkinson’s disease.
Robak LA; International Parkinson’s Disease Genomics Consortium (IPDGC), Heutink P, Shulman JM

Brain. 2017 Nov 13. doi: 10.1093/brain/awx285. [Epub ahead of print] PMID: 29140481

Review of ‘Mentored by a Madman:the William Burroughs Experiment’ by A.J. Lees, published by Notting Hill Editions, 2016.
O’Sullivan SS.

J Neurol Neurosurg Psychiatry. 2017 Mar;88(3):280. PMID: 28213511

No genetic association between attention-deficit/hyperactivity disorder (ADHD) and Parkinson’s disease in nine ADHD candidate SNPs.
Geissler JM; International Parkinson Disease Genomics Consortium members, Romanos M, Gerlach M, Berg D, Schulte C.

Atten Defic Hyperact Disord. 2017 Jun;9(2):121-127. PMID: 28176268

Discovery and functional prioritization of Parkinson’s disease candidate genes from large-scale whole exome sequencing.
Jansen IE; International Parkinson’s Disease Genetics Consortium (IPGDC), Heutink P.

Genome Biol. 2017 Jan 30;18(1):22. PMID: 28137300

Phenomenology and epidemiology of impulsive-compulsive behaviours in Parkinson’s disease, atypical Parkinsonian disorders and non-Parkinsonian populations.
Maloney EM, Djamshidian A, O’Sullivan SS.

J Neurol Sci. 2017 Mar 15;374:47-52.  PMID: 28108021

No genetic association between attention-deficit/hyperactivity disorder (ADHD) and Parkinson’s disease in nine ADHD candidate SNPs.
Geissler JM; International Parkinson Disease Genomics Consortium members., SchulteC.

Atten Defic Hyperact Disord. 2017 Feb 7. [Epub ahead of print] PMID: 28176268

Discovery and functional prioritization of Parkinson’s disease candidate genes from large-scale whole exome sequencing.
Jansen IE, Ye H, International Parkinson’s Disease Genetics Consortium (IPGDC), Heutink P.

Genome Biol. 2017 Jan 30;18(1):22. PMID: 28137300

A genome-wide association study in multiple system atrophy.
Sailer A, Scholz SW, Nalls MA, Schulte C, Federoff M, Price TR, Lees A, Ross OA, Dickson DW, Mok K, Mencacci NE, Schottlaender L, Chelban V, Ling H, O’Sullivan SS, Wood NW, Traynor BJ, Ferrucci L, Federoff HJ, Mhyre TR, Morris HR, Deuschl G, Quinn N, Widner H, Albanese A, Infante J, Bhatia KP, Poewe W, Oertel W, Höglinger GU, Wüllner U, Goldwurm S, Pellecchia MT, Ferreira J, Tolosa E, Bloem BR, Rascol O, Meissner WG, Hardy JA, Revesz T, Holton JL, Gasser T, Wenning GK, Singleton AB, Houlden H; European Multiple System Atrophy Study Group and the UK Multiple System Atrophy Study Group..

Neurology. 2016 Oct 11;87(15):1591-1598. PMID: 27629089

Palliative care for Parkinson’s disease: Patient and carer’s perspectives explored through qualitative interview.
Fox S, Cashell A, Kernohan WG, Lynch M, McGlade C, O’Brien T, O’Sullivan SS, Foley MJ, Timmons S.

Palliat Med. 2017 Jul;31(7):634-641. PMID:27683476

Augmentation and impulsivity in restless legs syndrome patients: A complex interaction.
O’Sullivan SS, Poyares D.

Neurology. 2016 Jul 5;87(1):15-6. PMID: 27261094

Severe Headache With Left Nasal Discharge: Is it Always Due to Autonomic Over Activity?
Bhattacharjee S, Elkider M, O’Sullivan S.Headache. 2016 Jan;56(1):162-3. doi: 10.1111/head.12705. Epub 2015 Oct 7.PMID: 26442991

Apomorphine: A potential modifier of amyloid deposition in Parkinson’s disease?
Yarnall AJ, Lashley T, Ling H, Lees AJ, Coleman SY, O’Sullivan SS, Compta Y, Revesz T, Burn DJ.

Mov Disord. 2016 May;31(5):668-75. PMID: 27156393

Jumping to conclusions in untreated patients with Parkinson’s disease.
de Rezende Costa FH, Averbeck B, O’Sullivan SS, Vincent MB, Rosso AL, Lees AJ, Djamshidian A.

Neuropsychologia. 2016 Mar 5;85:19-23. PMID: 26956927

Loss of VPS13C Function in Autosomal-Recessive Parkinsonism Causes Mitochondrial Dysfunction and Increases PINK1/Parkin-Dependent Mitophagy.
Lesage S, Drouet V, Majounie E; International Parkinson’s Disease Genomics Consortium (IPDGC)
Am J Hum Genet. 2016 Mar 3;98(3):500-13. PMID: 26942284

The Clinical Utility of a Low Serum Ceruloplasmin Measurement in the Diagnosis of Wilson Disease.
Kelly D, Crotty G, O’Mullane J, Stapleton M, Sweeney B, O’Sullivan SS.

Ir Med J. 2016 Jan;109(1):341-3. PMID: 26904791

Interviews with Irish healthcare workers from different disciplines about palliative care for people with Parkinson’s disease: a definite role but uncertainty around terminology and timing.
Fox S, Cashell A, Kernohan WG, Lynch M, McGlade C, O’Brien T, O’Sullivan SS, Timmons S.

BMC Palliat Care. 2016 Feb 9;15(1):15. PMID: 26860859

Psychogenic and neural visual-cue response in PD dopamine dysregulation syndrome.
Loane C, Wu K, O’Sullivan SS, Lawrence AD, Woodhead Z, Lees AJ, Piccini P, Politis M.

Parkinsonism Relat Disord. 2015 Nov;21(11):1336-41. PMID: 26427639

Morphometric changes in the reward system of Parkinson’s disease patients with impulse control disorders.
Pellicano C, Niccolini F, Wu K, O’Sullivan SS, Lawrence AD, Lees AJ, Piccini P, Politis M.

J Neurol. 2015 Dec;262(12):2653-61. PMID: 26410743

Rodent models of impulsive-compulsive behaviors in Parkinson’s disease: How far have we reached?
Cenci MA, Francardo V, O’Sullivan SS, Lindgren HS.

Neurobiol Dis. 2015 Oct;82:561-73. Review. PMID: 26325219

Clinical Reasoning: Vanishing tumor: A 7-year puzzle solved.
Kelly CM, O’Dowd S, Drake C, McCarthy L, Bermingham N, Fanning N, O’Sullivan SS, O’Reilly S.

Neurology. 2015 Sep 1;85(9):e69-73. PMID: 26324866

Survey of Health Care Workers Suggests Unmet Palliative Care Needs in Parkinson’s Disease.
Fox S, Gannon E, Cashell A, Kernohan WG, Lynch M, McGlade C, O’Brien T, O’Sullivan SS, Sweeney C, Timmons S.

Mov Disorders Clin Pract 04/2015; DOI: 10.1002/mdc3.12133

Single versus multiple impulse control disorders in Parkinson’s disease: an 11C-raclopride positron emission tomography study of reward cue-evoked striatal dopamine release.
Wu K, Politis M, O’Sullivan SS, Lawrence AD, Warsi S, Bose S, Lees AJ, Piccini P.

J Neurol. 2015 Jun;262(6):1504-14

Serotonergic markers in Parkinson’s disease and levodopa-induced dyskinesias.
Cheshire P, Ayton S, Bertram KL, Ling H, Li A, McLean C, Halliday GM, O’Sullivan SS, Revesz T, Finkelstein DI, Storey E, Williams DR.

Mov Disord. 2015 May;30(6):796-804. PMID: 25649148

NeuroX, a fast and efficient genotyping platform for investigation of neurodegenerative diseases.
Nalls MA, Bras J, Hernandez DG, International Parkinson’s Disease Genomics Consortium (IPDGC)., Singleton AB;.
Neurobiol Aging. 2015 Mar;36(3):1605.e7-12. PMID: 25444595

Perceptual decision-making in patients with Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Lawrence AD, Foltynie T, Aviles-Olmos I, Magdalinou N, Tomassini A,
Warner TT, Lees AJ, Averbeck BB.
J Psychopharmacol. 2014 Dec;28(12):1149-54. PMID: 25237123

Large-scale meta-analysis of genome-wide association data identifies six new risk loci for Parkinson’s disease.
Nalls MA, Pankratz N, Lill CM, International Parkinson’s Disease Genomics Consortium (IPDGC) et al., Singleton AB.
Nat Genet. 2014 Sep;46(9):989-93.

In a rush to decide: deep brain stimulation and dopamine agonist therapy in Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Tomassini A, Foltynie T, Limousin P, Aviles-Olmos I, Warner TT, Lees AJ, Averbeck BB.
J Parkinsons Dis. 2014;4(4):579-83. doi: 10.3233/JPD-140388.

Problematic Internet use in Parkinson’s disease.
Wu K, Politis M, O’Sullivan SS, Lawrence AD, Warsi S, Lees A, Piccini P.

Parkinsonism Relat Disord. 2014 May;20(5):482-7. PMID: 24582704

Unbiased screen for interactors of leucine-rich repeat kinase 2 supports a common pathway for sporadic and familial Parkinson disease.
Beilina A, Rudenko IN, Kaganovich A, Civiero L, Chau H, Kalia SK, Kalia LV, Lobbestael E, Chia R, Ndukwe K, Ding J, Nalls MA; International Parkinson’s Disease Genomics Consortium; North American Brain Expression Consortium, Olszewski M, Hauser DN, Kumaran R, Lozano AM, Baekelandt V, Greene LE, Taymans JM, Greggio E, Cookson MR.

Proc Natl Acad Sci U S A. 2014 Feb 18;111(7):2626-31.

Susceptibility loci for pigmentation and melanoma in relation to Parkinson’s disease.
Dong J, Gao J, Nalls M, Gao X, Huang X, Han J, Singleton AB, Chen H; International Parkinson’s Disease Genomics Consortium (IPDGC).

Neurobiol Aging. 2014 Jun;35(6):1512.e5-10

Impulsive and compulsive behaviors in Parkinson’s disease.
Averbeck BB, O’Sullivan SS, Djamshidian A.

Annu Rev Clin Psychol. 2014 Mar 28;10:553-80.

The unfolded protein response is activated in disease-affected brain regions in progressive supranuclear palsy and Alzheimer’s disease.
Stutzbach LD, Xie SX, Naj AC, Albin R, Gilman S; PSP Genetics Study Group, Lee VM, Trojanowski JQ, Devlin B, Schellenberg GD.

Acta Neuropathol Commun. 2013 Jul 6;1:31. PMID: 24252572

Genetic comorbidities in Parkinson’s disease.
Nalls MA, Saad M, Noyce AJ, Keller MF, Schrag A, Bestwick JP, Traynor BJ, Gibbs JR, Hernandez DG, Cookson MR, Morris HR, Williams N, Gasser T, Heutink P, Wood N, Hardy J, Martinez M, Singleton AB; International Parkinson’s Disease Genomics Consortium (IPDGC); Wellcome Trust Case Control Consortium 2 (WTCCC2); North American Brain Expression Consortium (NABEC); United Kingdom Brain Expression Consortium (UKBEC).

Hum Mol Genet. 2014 Feb 1;23(3):831-41. PMID: 24057672

Influence of single nucleotide polymorphisms in COMT , MAO-A and BDNF genes on dyskinesias and levodopa use in Parkinson’s disease.
Cheshire P, Bertram K, Ling H, O’Sullivan SS, Halliday G, McLean C, Bras J, Foltynie T, Storey E, Williams DR.

Neurodegener Dis. 2014;13(1):24-8. PMID: 24008922

Dopamine agonists rather than deep brain stimulation cause reflection impulsivity in Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Foltynie T, Aviles-Olmos I, Limousin P, Noyce A, Zrinzo L, Lees AJ, Averbeck BB.

J Parkinsons Dis. 2013;3(2):139-44

Impulsive-compulsive behaviours in Parkinson’s disease–prevention is better than cure.
Ryan SA, O’Sullivan SS.

Ir Med J. 2013 Jun;106(6):162.

Serum iron levels and the risk of Parkinson disease: a Mendelian randomization study.
Pichler I, Del Greco M F, Gögele M, Lill CM, Bertram L, Do CB, Eriksson N, Foroud T, Myers RH; PD GWAS Consortium, Nalls M, Keller MF; International Parkinson’s Disease Genomics Consortium; Wellcome Trust Case Control Consortium 2, Benyamin B, Whitfield JB; Genetics of Iron Status Consortium, Pramstaller PP, Hicks AA, Thompson JR, Minelli C.

PLoS Med. 2013;10(6):e1001462

The midbrain to pons ratio: a simple and specific MRI sign of progressive supranuclear palsy.
Massey LA, Jäger HR, Paviour DC, O’Sullivan SS, Ling H, Williams DR, Kallis C, Holton J, Revesz T, Burn DJ, Yousry T, Lees AJ, Fox NC, Micallef C.

Neurology. 2013 May 14;80(20):1856-61. PMID: 2361616

Uncertainty about mapping future actions into rewards may underlie performance on multiple measures of impulsivity in behavioral addiction: evidence from Parkinson’s disease.
Averbeck BB, Djamshidian A, O’Sullivan SS, Housden CR, Roiser JP, Lees AJ.

Behav Neurosci. 2013 Apr;127(2):245-55. PMID: 23565936

The Val158Met COMT polymorphism is a modifier of the age at onset in Parkinson’s disease with a sexual dimorphism.
Klebe S, Golmard JL, Nalls MA, Saad M, Singleton AB, Bras JM, Hardy J, Simon-Sanchez J, Heutink P, Kuhlenbäumer G, Charfi R, Klein C, Hagenah J, Gasser T, Wurster I, Lesage S, Lorenz D, Deuschl G, Durif F, Pollak P, Damier P, Tison F, Durr A, Amouyel P, Lambert JC, Tzourio C, Maubaret C, Charbonnier-Beaupel F, Tahiri K, Vidailhet M, Martinez M, Brice A, Corvol JC; French Parkinson’s Disease Genetics Study Group; International Parkinson’s Disease Genomics Consortium (IPDGC).

J Neurol Neurosurg Psychiatry. 2013 Jun;84(6):666-73. PMID: 23408064

Neural response to visual sexual cues in dopamine treatment-linked hypersexuality in Parkinson’s disease.
Politis M, Loane C, Wu K, O’Sullivan SS, Woodhead Z, Kiferle L, Lawrence AD, Lees AJ, Piccini P.

Brain. 2013 Feb;136(Pt 2):400-11. PMID: 23378222

Trial of CBT for impulse control behaviors affecting Parkinson patients and their caregivers.
Okai D, Askey-Jones S, Samuel M, O’Sullivan SS, Chaudhuri KR, Martin A, Mack J, Brown RG, David AS.

Neurology. 2013 Feb 26;80(9):792-9

Increased reflection impulsivity in patients with ephedrone-induced Parkinsonism.
Djamshidian A, Sanotsky Y, Matviyenko Y, O’Sullivan SS, Sharman S, Selikhova M, Fedoryshyn L, Filts Y, Bearn J, Lees AJ, Averbeck BB.

Addiction. 2013 Apr;108(4):771-9

MM2 subtype of sporadic Creutzfeldt-Jakob disease may underlie the clinical presentation of progressive supranuclear palsy.
Petrovic IN, Martin-Bastida A, Massey L, Ling H, O’Sullivan SS, Williams DR, Holton JL, Revesz T, Ironside JW, Lees AJ, Silveira-Moriyama L.

J Neurol. 2013 Apr;260(4):1031-6

Using genome-wide complex trait analysis to quantify ‘missing heritability’ in Parkinson’s disease.
Keller MF, Saad M, Bras J, Bettella F, Nicolaou N, Simón-Sánchez J, Mittag F, Büchel F, Sharma M, Gibbs JR, Schulte C, Moskvina V, Durr A, Holmans P, Kilarski LL, Guerreiro R, Hernandez DG, Brice A, Ylikotila P, Stefánsson H, Majamaa K, Morris HR, Williams N, Gasser T, Heutink P, Wood NW, Hardy J, Martinez M, Singleton AB, Nalls MA; International Parkinson’s Disease Genomics Consortium (IPDGC); Wellcome Trust Case Control Consortium 2 (WTCCC2).

Hum Mol Genet. 2013 Jul 15;22(14):2973. PMID: 22892372

Recognition of psychogenic non-epileptic seizures: a curable neurophobia?
O’Sullivan SS, Redwood RI, Hunt D, McMahon EM, O’Sullivan S.

J Neurol Neurosurg Psychiatry. 2013 Feb;84(2):228-31

Decision making, impulsivity, and addictions: Do Parkinson’s disease patients jump to conclusions?
Djamshidian A, O’Sullivan SS, Sanotsky Y, Sharman S, Matviyenko Y, Foltynie T, Michalczuk R, Aviles-Olmos I, Fedoryshyn L, Doherty KM, Filts Y, Selikhova M, Bowden-Jones H, Joyce E, Lees AJ, Averbeck BB.
Mov Disord. 2012 Aug;27(9):1137-45.

Conventional magnetic resonance imaging in confirmed progressive supranuclear palsy and multiple system atrophy.
Massey LA, Micallef C, Paviour DC, O’Sullivan SS, Ling H, Williams DR, Kallis C, Holton JL, Revesz T, Burn DJ, Yousry T, Lees AJ, Fox NC, Jäger HR.
Mov Disord. 2012 Dec;27(14):1754-62.

Effects of dopamine on sensitivity to social bias in Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Lees A, Averbeck BB.
PLoS One. 2012;7(3):e32889. Epub 2012 Mar 9.

Putaminal Upregulation of FosB/ΔFosB-Like Immunoreactivity in Parkinson’s Disease Patients with Dyskinesia
Lindgren HS, Rylander D, Iderberg H, Andersson M, O’Sullivan SS, Williams DR, Lees AJ, Cenci MA.
J Parkinsons dis 2011; 1 (4) 347-357

Testing an aetiological model of visual hallucinations in Parkinson’s disease.
Gallagher DA, Parkkinen L, O’Sullivan SS, Spratt A, Shah A, Davey CC, Bremner FD, Revesz T, Williams DR, Lees AJ, Schrag A.
Brain. 2011 Nov;134(Pt 11):3299-309. Epub 2011 Sep 15.

Disentangling the Relationship between Lewy Bodies and Nigral Neuronal Loss in Parkinson’s Disease
Parkkinen L, O’Sullivan SS, Collins C, Petrie A, Holton JL, Revesz T, Lees AJ.
J Parkinsons dis 2011; 1 (3) 277-286

Does levodopa accelerate the pathologic process in Parkinson disease brain?
Parkkinen L, O’Sullivan SS, Kuoppamäki M, Collins C, Kallis C, Holton JL, Williams DR, Revesz T, Lees AJ.
Neurology. 2011 Oct 11;77(15):1420-6. Epub 2011 Sep 14.

Clinical aspects of impulsive compulsive behaviours in Parkinson’s disease.
Djamshidian A, Averbeck BB, Lees AJ, O’Sullivan SS.
J Neurol Sci. 2011 Nov 15;310(1-2):183-8. Epub 2011 Aug 11. Review.

Globular glial tauopathies (GGT) presenting with motor neuron disease or frontotemporal dementia: an emerging group of 4-repeat tauopathies.
Ahmed Z, Doherty KM, Silveira-Moriyama L, Bandopadhyay R, Lashley T, Mamais A, Hondhamuni G, Wray S, Newcombe J, O’Sullivan SS, Wroe S, de Silva R, Holton JL, Lees AJ, Revesz T.
Acta Neuropathol. 2011 Oct;122(4):415-28.

Vascular endothelial growth factor is upregulated by L-dopa in the parkinsonian brain: implications for the development of dyskinesia.
Ohlin KE, Francardo V, Lindgren HS, Sillivan SE, O’Sullivan SS, Luksik AS, Vassoler FM, Lees AJ, Konradi C, Cenci MA.
Brain. 2011 Aug;134(Pt 8):2339-57. Epub 2011 Jul 19.

A two-stage meta-analysis identifies several new loci for Parkinson’s disease.
International Parkinson’s Disease Genomics Consortium (IPDGC); Wellcome Trust Case Control Consortium 2 (WTCCC2).
PLoS Genet. 2011 Jun;7(6):e1002142. Epub 2011 Jun 30.

LRRK2 expression in idiopathic and G2019S positive Parkinson’s disease subjects: a morphological and quantitative study.
Sharma S, Bandopadhyay R, Lashley T, Renton AE, Kingsbury AE, Kumaran R, Kallis C, Vilariño-Güell C, O’Sullivan SS, Lees AJ, Revesz T, Wood NW, Holton JL.
Neuropathol Appl Neurobiol. 2011 Dec;37(7):777-90.

Identification of common variants influencing risk of the tauopathy progressive supranuclear palsy.
Höglinger GU, Melhem NM, et al on behalf of the PSP Genetics Study Group.
Nat Genet. 2011 Jun 19;43(7):699-705. doi: 10.1038/ng.859.

Glucocerebrosidase mutations do not cause increased Lewy body pathology in Parkinson’s disease.
Parkkinen L, Neumann J, O’Sullivan SS, Holton JL, Revesz T, Hardy J, Lees AJ.
Mol Genet Metab. 2011 Aug;103(4):410-2. Epub 2011 May 5.

Lewy- and Alzheimer-type pathologies in Parkinson’s disease dementia: which is more important?
Compta Y, Parkkinen L, O’Sullivan SS, Vandrovcova J, Holton JL, Collins C, Lashley T, Kallis C, Williams DR, de Silva R, Lees AJ, Revesz T.
Brain. 2011 May;134(Pt 5):1493-505.

Novelty seeking behaviour in Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Wittmann BC, Lees AJ, Averbeck BB.
Neuropsychologia. 2011 Jul;49(9):2483-8. Epub 2011 May 4.

Salivary cortisol levels in Parkinson’s disease and its correlation to risk behaviour.
Djamshidian A, O’Sullivan SS, Papadopoulos A, Bassett P, Shaw K, Averbeck BB, Lees A.
J Neurol Neurosurg Psychiatry. 2011 Oct;82(10):1107-11. Epub 2011 Apr 8.

Cue-induced striatal dopamine release in Parkinson’s disease-associated impulsive-compulsive behaviours.
O’Sullivan SS, Wu K, Politis M, Lawrence AD, Evans AH, Bose SK, Djamshidian A, Lees AJ, Piccini P.
Brain. 2011 Apr;134(Pt 4):969-78. Epub 2011 Feb 24.

The effect of drug treatment on neurogenesis in Parkinson’s disease.
O’Sullivan SS, Johnson M, Williams DR, Revesz T, Holton JL, Lees AJ, Perry EK.
Mov Disord. 2011 Jan;26(1):45-50.

Stroop test performance in impulsive and non impulsive patients with Parkinson’s disease.
Djamshidian A, O’Sullivan SS, Lees A, Averbeck BB.
Parkinsonism Relat Disord. 2011 Mar;17(3):212-4.

Altruistic punishment in patients with Parkinson’s disease with and without impulsive behaviour.
Djamshidian A, O’Sullivan SS, Doherty K, Lees AJ, Averbeck BB.
Neuropsychologia. 2011 Jan;49(1):103-7.

Maladaptive plasticity of serotonin axon terminals in levodopa-induced dyskinesia.
Rylander D, Parent M, O’Sullivan SS, Dovero S, Lees AJ, Bezard E, Descarries L, Cenci MA.
Ann Neurol. 2010 Nov;68(5):619-28.

Risk and learning in impulsive and nonimpulsive patients with Parkinson’s disease.
Djamshidian A, Jha A, O’Sullivan SS, Silveira-Moriyama L, Jacobson C, Brown P, Lees A, Averbeck BB.
Mov Disord. 2010 Oct 15;25(13):2203-10.

Intact reward learning but elevated delay discounting in Parkinson’s disease patients with impulsive-compulsive spectrum behaviors.
Housden CR, O’Sullivan SS, Joyce EM, Lees AJ, Roiser JP.
Neuropsychopharmacology. 2010 Oct;35(11):2155-64.

Does corticobasal degeneration exist? A clinicopathological re-evaluation.
Ling H, O’Sullivan SS, Holton JL, Revesz T, Massey LA, Williams DR, Paviour DC, Lees AJ.
Brain. 2010 Jul;133(Pt 7):2045-57.

Sleep disturbance and impulsive-compulsive behaviours in Parkinson’s disease.
O’Sullivan SS, Loane CM, Lawrence AD, Evans AH, Piccini P, Lees AJ.
J Neurol Neurosurg Psychiatry. 2011 Jun;82(6):620-2.

Relationships between age and late progression of Parkinson’s disease: a clinico-pathological study.
Kempster PA, O’Sullivan SS, Holton JL, Revesz T, Lees AJ.
Brain. 2010 Jun;133(Pt 6):1755-62.

Impulsive-compulsive spectrum behaviors in pathologically confirmed progressive supranuclear palsy.
O’Sullivan SS, Djamshidian A, Ahmed Z, Evans AH, Lawrence AD, Holton JL, Revesz T, Lees AJ.
Mov Disord. 2010 Apr 15;25(5):638-42.

Excessive hoarding in Parkinson’s disease.
O’Sullivan SS, Djamshidian A, Evans AH, Loane CM, Lees AJ, Lawrence AD.
Mov Disord. 2010 Jun 15;25(8):1026-33.

Progressive supranuclear palsy syndrome presenting as progressive nonfluent aphasia: a neuropsychological and neuroimaging analysis.
Rohrer JD, Paviour D, Bronstein AM, O’Sullivan SS, Lees A, Warren JD.
Mov Disord. 2010 Jan 30;25(2):179-88.

Reckless generosity in Parkinson’s disease.
O’Sullivan SS, Evans AH, Quinn NP, Lawrence AD, Lees AJ.
Mov Disord. 2010 Jan 30;25(2):221-3.

A review of nerve conduction studies in cases of suspected compression neuropathies of the upper limb.
Neligan A, O’Sullivan SS, Mullins GM, McCarthy A, Kowalski RG, Kinsella J, McNamara B.
Eur Neurol. 2010;63(1):11-6.

Degeneration in different parkinsonian syndromes relates to astrocyte type and astrocyte protein expression.
Song YJ, Halliday GM, Holton JL, Lashley T, O’Sullivan SS, McCann H, Lees AJ, Ozawa T, Williams DR, Lockhart PJ, Revesz TR.
J Neuropathol Exp Neurol. 2009 Oct;68(10):1073-83.

Concomitant progressive supranuclear palsy and multiple system atrophy: more than a simple twist of fate?
Silveira-Moriyama L, González AM, O’Sullivan SS, Williams DR, Massey L, Parkkinen L, Ahmed Z, de Silva R, Chacón JR, Revesz T, Lees AJ, Holton JL.
Neurosci Lett. 2009 Dec 31;467(3):208-11.

Dopamine dysregulation syndrome, impulse control disorders and punding after deep brain stimulation surgery for Parkinson’s disease.
Lim SY, O’Sullivan SS, Kotschet K, Gallagher DA, Lacey C, Lawrence AD, Lees AJ, O’Sullivan DJ, Peppard R, Rodrigues JP, Schrag A, Silberstein P, Tisch S, Evans AH.
Journal of Clinical Neuroscience. 2009 Sep;16(9):1148-52

Glucocerebrosidase mutations in clinical and pathologically proven Parkinson’s disease.
Neumann J, Bras J, Deas E, O’Sullivan SS, Parkkinen L, Lachmann RH, Li A, Holton J, Guerreiro R, Paudel R, Segarane B, Singleton A, Lees A, Hardy J, Houlden H, Revesz T, Wood NW.
Brain. 2009 Jul;132(Pt 7):1783-94. Epub 2009 Mar 13.

Evidence for pre and postsynaptic nigrostriatal dysfunction in the fragile X tremor-ataxia syndrome.
Healy DG, Bressman S, Dickson J, Silveira-Moriyama L, Schneider SA, Sullivan SS, Massey L, Bhatia KP, Shaw K, Bhatia KP, Bomanji J, Wood NW, Lees AJ.
Mov Disord. 2009 Jun 15;24(8):1245-7.

Dopamine dysregulation syndrome: an overview of its epidemiology, mechanisms and management.
O’Sullivan SS, Evans AH, Lees AJ.
CNS Drugs. 2009;23(2):157-70. doi: 10.2165/00023210-200923020-00005. Review.

Parkinson’s disease with Onuf’s nucleus involvement mimicking multiple system atrophy.
O’Sullivan SS, Massey LA, Williams DR, Revesz T, Lees A, Holton J.
BMJ Case Rep. 2009;2009. pii: bcr08.2008.0774. Epub 2009 Feb 2.

Normal dopamine transporter single photon-emission CT scan in corticobasal degeneration.
O’Sullivan SS, Burn DJ, Holton JL, Lees AJ.
Mov Disord. 2008 Dec 15;23(16):2424-6.

A rare cause of fatal intracranial haemorrhage.
Neligan A, Mullins GM, O’Sullivan SS, Fitzgerald P, Harrington H.
Ir J Med Sci. 2009 Sep;178(3):343-5. Epub 2008 Sep 24.

Phenotype, genotype, and worldwide genetic penetrance of LRRK2-associated Parkinson’s disease: a case-control study.
Healy DG, Falchi M, O’Sullivan SS, Bonifati V, Durr A, Bressman S, Brice A, Aasly J, Zabetian CP, Goldwurm S, Ferreira JJ, Tolosa E, Kay DM, Klein C, Williams DR, Marras C, Lang AE, Wszolek ZK, Berciano J, Schapira AH, Lynch T, Bhatia KP, Gasser T, Lees AJ, Wood NW; International LRRK2 Consortium.
Lancet Neurol. 2008 Jul;7(7):583-90. Epub 2008 Jun 6.

Venous and arterial thrombo-embolic complications of hormonal treatment in a male-to-female transgender patient.
Mullins GM, O’Sullivan SS, Kinsella J, McEnroy D, Crimmins D, Whyte S, Sturm JW.
J Clin Neurosci. 2008 Jun;15(6):714-6. Epub 2008 Apr 18.

Aetiology and prognosis of encephalopathic patterns on electroencephalogram in a general hospital.
O’Sullivan SS, Neligan A, Mullins GM, Daly S, McNamara B, Galvin R, Sweeney B.
J Clin Neurosci. 2008 Jun;15(6):637-42..

Clinical outcomes of progressive supranuclear palsy and multiple system atrophy.
O’Sullivan SS, Massey LA, Williams DR, Silveira-Moriyama L, Kempster PA, Holton JL, Revesz T, Lees AJ.
Brain. 2008 May;131(Pt 5):1362-72. Epub 2008 Apr 2.

A role for myelography in assessing paraparesis.
Merwick A, O’Sullivan SS, O’Regan KN, Marks CJ, Ryders DQ, Sweeney BJ.
Ir Med J. 2008 Jan;101(1):21-2.

Cortical alpha-synuclein load is associated with amyloid-beta plaque burden in a subset of Parkinson’s disease patients.
Lashley T, Holton JL, Gray E, Kirkham K, O’Sullivan SS, Hilbig A, Wood NW, Lees AJ, Revesz T.
Acta Neuropathol. 2008 Apr;115(4):417-25. Epub 2008 Jan 8.

Punding in Parkinson’s disease.
O’Sullivan SS, Evans AH, Lees AJ.
Pract Neurol. 2007 Nov;7(6):397-9. No abstract available.

Nonmotor symptoms as presenting complaints in Parkinson’s disease: a clinicopathological study.
O’Sullivan SS, Williams D, Gallagher D, Massey LA, Silveira-Moriyama L, Lees AJ.
Mov Disord. 2008 Jan;23(1):101-6.

Parkinson’s disease with Onuf’s nucleus involvement mimicking multiple system atrophy.
O’Sullivan SS, Holton JL, Massey LA, Williams DR, Revesz T, Lees AJ.
J Neurol Neurosurg Psychiatry. 2008 Feb;79(2):232-4.

Aseptic meningitis: a 2-year review of diagnoses reached in a tertiary neurological and infectious disease centre.
O’Sullivan SS, O’Connell B, Redmond J.
Ir J Med Sci. 2007 Sep;176(3):215-9. Epub 2007 Jul 21.

Non-traumatic brachial plexopathies, clinical, radiological and neurophysiological findings from a tertiary centre.
Mullins GM, O’Sullivan SS, Neligan A, Daly S, Galvin R, Sweeney B, McNamara B
Clin Neurol Neurosurg. 2007 Oct;109(8):661-6. Epub 2007 Jul 10.

Pathological gambling in Parkinson’s disease: risk factors and differences from dopamine dysregulation. An analysis of published case series.
Gallagher DA, O’Sullivan SS, Evans AH, Lees AJ, Schrag A.
Mov Disord. 2007 Sep 15;22(12):1757-63.

Clinical characteristics and outcome of patients diagnosed with psychogenic nonepileptic seizures: a 5-year review.
O’Sullivan SS, Spillane JE, McMahon EM, Sweeney BJ, Galvin RJ, McNamara B, Cassidy EM.
Epilepsy Behav. 2007 Aug;11(1):77-84. Epub 2007 May 22.

Pathological gambling in Parkinson’s disease.
O’Sullivan SS, Lees AJ.
Lancet Neurol. 2007 May;6(5):384-6.

Detection rates of sexual dysfunction amongst patients with multiple sclerosis in an outpatient setting–can this be improved?
O’Sullivan SS, Hardiman O.
Ir Med J. 2006 Nov-Dec;99(10):304-6.

Acquired generalised neuromyotonia, cutaneous lupus erythematosus and alopecia areata in a patient with myasthenia gravis.
O’Sullivan SS, Mullins GM, Neligan A, McNamara B, Galvin RJ.
Clin Neurol Neurosurg. 2007 May;109(4):374-5.

A study of idiopathic generalised epilepsy in an Irish population.
Mullins GM, O’sullivan SS, Neligan A, McCarthy A, McNamara B, Galvin RJ, Sweeney BJ.
Seizure. 2007 Apr;16(3):204-10. Epub 2007 Jan 12.

ALS in a patient with hereditary neuropathy with liability to pressure palsy.
O’Sullivan SS, McCarthy A, Mullins GM, McNamara B, Sweeney BJ.
Neurology. 2006 Dec 26;67(12):2260.

Late-onset ophthalmoplegic migraine in a patient with previous childhood abdominal migraine.
O’Sullivan SS, O’Regan KN, Tormey P, Galvin RJ.
Cephalalgia. 2006 Aug;26(8):1033-5.

The role of the standard EEG in clinical psychiatry.
O’Sullivan SS, Mullins GM, Cassidy EM, McNamara B.
Hum Psychopharmacol. 2006 Jun;21(4):265-71.

Panniculitis and lipoatrophy after subcutaneous injection of interferon beta-1b in a patient with multiple sclerosis.
O’Sullivan SS, Cronin EM, Sweeney BJ, Bourke JF, Fitzgibbon J.
J Neurol Neurosurg Psychiatry. 2006 Dec;77(12):1382-3.

The opinion of the general practitioner toward clinical management of patients with psychogenic nonepileptic seizures.
O’Sullivan SS, Sweeney BJ, McNamara B.
Epilepsy Behav. 2006 Feb;8(1):256-60.

Insulinoma presenting as refractory late-onset epilepsy.
O’Sullivan SS, Redmond J.
Epilepsia. 2005 Oct;46(10):1690-1.

 

Review papers and Editorials

Clinical aspects of impulsive compulsive behaviours in Parkinson’s disease.
Djamshidian A, Averbeck BB, Lees AJ, O’Sullivan SS.
J Neurol Sci. 2011 Nov 15;310(1-2):183-8.

Dopamine dysregulation syndrome: an overview of its epidemiology, mechanisms and management.
O’Sullivan SS, Evans AH, Lees AJ.
CNS Drugs. 2009;23(2):157-70.

Punding in Parkinson’s disease.
O’Sullivan SS, Evans AH, Lees AJ.
Pract Neurol. 2007 Nov;7(6):397-9.

Pathological gambling in Parkinson’s disease.
O’Sullivan SS, Lees AJ.
Lancet Neurol. 2007 May;6(5):384-6.

O’Sullivan SS, Cassidy EM.
“Somatoform disorder: a raison d’etre for Liaison Psychiatry”
Ir J Psych Med. 2006; 23(4): 128-130

 

Book Chapters

O’Sullivan SS. “Chapter 12: Football and Movement Disorders” in “Letters for Andrew” ed. Ockelford and Butler. Virginia Keiley Publishing, London, 2008.

O’Sullivan SS, Lees AJ. “Chapter 19: The Dopamine Dysregulation Syndrome” in “The Non-Motor and Non-Dopaminergic Features of Parkinson’s Disease” eds. Olanow, Stocchi and Lang. Blackwell Publishing, Oxford. 2011.

Massey LA, O’Sullivan SS. “Corticobasal degeneration” in “Imaging in Neurodegenerative Disorders”, Ed. Saba. Oxford University Press, Oxford. 2014.

Djamshidian A, O’Sullivan SS. “Neuroleptic malignant syndrome” in “Medication-Induced Movement Disorders”, Ed. Friedman. Cambridge University Press, Cambridge. 2015.