Research Article
Volume 11 Issue 4 - 2020
New Insight into Correlation between Convergence Insufficiency/ Vestibular Abnormalities and Depression in Post-Concussion Syndrome
Neda Anssari1,4, Abdelbaset Suleiman2, Mehrangiz Ashiri2, Brian J Lithgow2,3, Zahra Moussavi2 and Behzad Mansouri1,2,4,5*
1Department of Internal Medicine, Section of Neurology, University of Manitoba, Manitoba, Canada
2Biomedical Engineering Program, University of Manitoba, Manitoba, Canada
3Monash Alfred Psychiatry Research Center, Monash University, Melbourne, Australia
4iScope Concussion and Pain Clinic, Toronto, Ontario, Canada
5Department of Ophthalmology, University of Manitoba, Winnipeg, Manitoba, Canada
*Corresponding Author: Behzad Mansouri, Department of Internal Medicine, Section of Neurology, University of Manitoba, Manitoba, Canada.
Received: May 14, 2020; Published: June 24, 2020


Post-concussion syndrome (PCS) causes a variety of cognitive/somatic symptoms. We previously showed that in PCS, convergence insufficiency (CI) was correlated with vestibular abnormality (VA). The cause of depression in PCS is not completely understood; however, neurotransmitter (e.g. serotonin) abnormalities play a significant role; the neurotransmitters like serotonin are mainly produced in brainstem. It is conceivable that damage to axons transporting neurotransmitters to the cortex, are responsible for cortical deficits. Previous studies suggest that (a) depression recovery in PCS is parallel to other PCS symptoms, and (b) depressed patients are less motivated and have a tendency to exaggerate their physical/cognitive deficiencies. Our results are in contrast with both of these suggestions.

Forty-eight PCS patients were tested with Electrovestibulography (EVestG) and the Montgomery-Asberg-Depression-Rating-Scale (MADRS). The last twenty patients were also tested with Rivermead-post-concussion-questionnaire (RPQ). Field Potential (FP) area was extracted and analyzed from EVestG data. CI was measured using prism-bars/cross-cover examination at near.

We previously reported that in PCS, FP-area and CI were significantly correlated. Here we report that based on MADRS score, CI is highest in the PCS without depression (CI = 7.5(PD) ± 1.2(SE)), moderate (CI = 5.2 ± 1.0) with mild-depression, and lowest with moderate/severe depression (CI = 1.6 ± 0.7).

We demonstrated a negative correlation between CI and depression in PCS, so lack of motivation in PCS did not play a significant role. Depression is likely localized to supra-tentorial brain areas although the source of the deficit might still be infratentorial, whereas CI/VA is associated with brainstem damage. We conclude that PCS generates mixed heterogeneous supra- and infra-tentorial neurological symptoms.

Keywords: Mild Traumatic Brain Injury; mTBI; Concussion; Post-Concussion Syndrome; PCS; Electrovestibulography; EVestG; Vergence Eye Movement; Convergence Insufficiency; Depression


  1. Iverson GL and Lange RT. “Post-concussion syndrome”. In: The Little Black Book of Neuropsychology. Springer (2011): 745-763.
  2. Daroff RB., et al. “Bradley’s Neurology in Clinical Practice E-Book”. Elsevier Health Sciences (2015).
  3. King NS and Kirwilliam S. “Permanent post-concussion symptoms after mild head injury”. Brain International Journal5 (2011): 462-470.
  4. Ibrahim NG., et al. “Physiological and pathological responses to head rotations in toddler piglets”. Journal of Neurotrauma 6 (2010): 1021-1035.
  5. Gardner RC and Yaffe K. “Epidemiology of mild traumatic brain injury and neurodegenerative disease”. Molecular and Cellular Neuroscience 66 (2015): 75-80.
  6. Belanger HG., et al. “Factors moderating neuropsychological outcomes following mild traumatic brain injury: a meta-analysis”. Journal of the International Neuropsychological Society 3 (2005): 215-227.
  7. Cassidy JD., et al. “Incidence, risk factors and prevention of mild traumatic brain injury: results of the WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury”. Journal of Rehabilitation Medicine 36 (2004): 28-60.
  8. Iverson GL. “Outcome from mild traumatic brain injury”. Current Opinion in Psychiatry 3 (2005): 301-317.
  9. Ponsford J., et al. “Functional outcome 10 years after traumatic brain injury: its relationship with demographic, injury severity, and cognitive and emotional status”. Journal of the International Neuropsychological Society 2 (2008): 233-242.
  10. Sherer M., et al. “Neuropsychological Assessment and Employment Outcome After Traumatic Brain Injury: A Review”. The Clinical Neuropsychologist 2 (2002): 157-178.
  11. Nelson LD., et al. “Recovery after Mild Traumatic Brain Injury in Patients Presenting to US Level i Trauma Centers: A Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) Study”. JAMA Neurology 9 (2019): 1049-1059.
  12. Suleiman A., et al. “Correlation between Ocular and Vestibular Abnormalities and Convergence Insufficiency in Post-Concussion Syndrome”. Neuro-Ophthalmology (2019).
  13. Atkins EJ., et al. “Post-traumatic visual loss”. Reviews in Neurological Diseases 2 (2008): 73-81.
  14. Ciuffreda KJ., et al. “Occurrence of oculomotor dysfunctions in acquired brain injury: A retrospective analysis”. Journal of the American Optometric Association 4 (2007): 155-161.
  15. Szymanowicz D., et al. “Vergence in mild traumatic brain injury: a pilot study”. Journal of Rehabilitation Research and Development 7 (2012): 1083-1100.
  16. Pearce KL., et al. “Near Point of Convergence After a Sport-Related Concussion”. American Journal Sports Medicines12 (2015): 3055-3061.
  17. Heitger MH., et al. “Impaired eye movements in post-concussion syndrome indicate suboptimal brain function beyond the influence of depression, malingering or intellectual ability”. Brain 10 (2009): 2850-2870.
  18. Capó-Aponte JE., et al. “Visual dysfunctions and symptoms during the subacute stage of blast-induced mild traumatic brain injury”. Mil Medicine7 (2012): 804-813.
  19. Rucker JC and Phillips PH. “Efferent Vision Therapy”. Journal of Neuro-Ophthalmology 2 (2017): 230-236.
  20. Barnett BP and Singman EL. “Vision Concerns After Mild Traumatic Brain Injury”. Current Treatment Options in Neurology 2 (2015): 5.
  21. Hellerstein LF., et al. “Vision profile of patients with mild brain injury”. Journal of the American Optometric Association 10 (1995): 634-639.
  22. Samadani U. “Will eye tracking change the way we diagnose and classify concussion and structural brain injury?” Concussion 1 (2016): 1-3.
  23. Maruta J., et al. “Association of Visual Tracking Metrics With Post-concussion Symptomatology”. Frontiers in Neurology (2018): 9.
  24. Jury MA and Flynn MC. “Auditory and vestibular sequelae to traumatic brain injury: a pilot study”. The New Zealand Medical Journal 1134 (2001): 286-288.
  25. Valovich McLeod TC and Hale TD. “Vestibular and balance issues following sport-related concussion”. Brain International Journal2 (2015): 175-184.
  26. Suleiman A., et al. “Quantitative measurement of post-concussion syndrome Using Electrovestibulography”. Scientific Reports 1 (2017): 16371.
  27. Kontos AP., et al. “Review of Vestibular and Oculomotor Screening and Concussion Rehabilitation”. Journal of Athletic Training 3 (2017): 256-261.
  28. Mucha A., et al. “A Brief Vestibular/Ocular Motor Screening (VOMS) assessment to evaluate concussions: preliminary findings”. American Journal of Sports Medicine 10 (2014): 2479-2486.
  29. Lithgow B. “A Methodology for Detecting Field Potentials from the External Ear Canal: NEER and EVestG”. Annals of Biomedical Engineering 408 (2012): 1835-1850.
  30. Lithgow B., et al. “EVestG Recordings are Vestibuloacoustic Signals”. Journal of Medical and Biological Engineerin (2018).
  31. Suleiman A., et al. “Using EVestG Assessments for Detection of Symptomology Consequent to a Lateral-Impact Concussion”. Journal of Medical and Biological Engineering (2018).
  32. Suleiman A., et al. “Investigating the Feasibility of EVestG Assessment for Screening Concussion”. Eng Med Biol Soc (EMBC), 2015 37th Annual International Conference IEEE. (2015): 3375-3378.
  33. Suleiman A. “Application of electrovestibulography on post-concussion syndrome: diagnosis and monitoring (2019).
  34. Suleiman A., et al. “Investigating the validity and reliability of Electrovestibulography (EVestG) for detecting post-concussion syndrome (PCS) with and without comorbid depression”. Scientific Reports 1 (2018): 14495.
  35. Moussavi Z., et al. “A Pilot Randomised Double-Blind Study of the Tolerability and efficacy of repetitive Transcranial Magnetic Stimulation on Persistent Post-Concussion Syndrome”. Scientific Reports 1 (2019): 5498.
  36. Callier S., et al. “Evolution and cell biology of dopamine receptors in vertebrates”. Biology of the Cell 7 (2003): 489-502.
  37. Vincent JD., et al. “[Evolution of monoamine receptors and the origin of motivational and emotional systems in vertebrates]”. Bulletin de L'Académie Nationale de Médecine 7 (1998):1505-15614.
  38. BilZ0r E. “The Neuropharmacology of Hallucinogens: A Technical Overview”. Erowid Pharmacology Vaults (2005).
  39. Kenneth L. “Neuropsychopharmacology - 5th Generation of Progress”. Philadelphia, Pa.: Lippincott Williams and Wilkins (2002).
  40. Peyron C., et al. “Forebrain afferents to the rat dorsal raphe nucleus demonstrated by retrograde and anterograde tracing methods”. Neuroscience 2 (1998): 443-468.
  41. Ruhé HG., et al. “Mood is indirectly related to serotonin, norepinephrine and dopamine levels in humans: A meta-analysis of monoamine depletion studies”. Molecular Psychiatry 4 (2007): 331-359.
  42. Araneda R and Andrade R. “5-Hydroxytryptamine2 and 5-hydroxytryptamine 1A receptors mediate opposing responses on membrane excitability in rat association cortex”. Neuroscience 2 (1991): 399-412.
  43. Davies MF., et al. “Two distinct effects of 5-hydroxytryptamine on single cortical neurons”. Brain Research 1-2 (1987): 347-352.
  44. Sheldon PW and Aghajanian GK. “Serotonin (5-HT) induces IPSPs in pyramidal layer cells of rat piriform cortex: evidence for the involvement of a 5-HT2-activated interneuron”. Brain Research 1 (1990): 62-69.
  45. Mele T., et al. “Regulatory role of monoamine neurotransmitters in astrocytic NT-3 synthesis”. International Journal of Developmental Neuroscience 1 (2010): 13-19.
  46. Dekosky ST., et al. “Interleukin-1 receptor antagonist suppresses neurotrophin response in injured rat brain”. Annals of Neurology 1 (1996): 123-127.
  47. Delgado PL and Moreno FA. “Role of norepinephrine in depression”. The Journal of Clinical Psychiatry 1 (2000): 5-12.
  48. Feeney DM., et al. “The locus coeruleus and cerebral metabolism: Recovery of function after cortical injury”. Physiological Psychology 3 (1985): 197-203.
  49. Pappius HM. “Significance of biogenic amines in functional disturbances resulting from brain injury”. Metabolic Brain Disease 4 (1988): 303-310.
  50. Barnes GR. “Cognitive processes involved in smooth pursuit eye movements”. Brain and Cognition 3 (2008): 309-326.
  51. Hutton SB. “Cognitive control of saccadic eye movements”. Brain and Cognition 3 (2008): 327-340.
  52. Leigh R and Zee D. “The Neurology of Eye Movements” (2015).
  53. Schutz AC., et al. “Eye movements and perception: A selective review”. Journal of Vision 5 (2011): 9-9.
  54. Schretlen DJ and Shapiro AM. “A quantitative review of the effects of traumatic brain injury on cognitive functioning”. International Review of Psychiatry 4 (2003): 341-349.
  55. Collie A and Maruff P. “Computerised neuropsychological testing”. British Journal of Sports Medicine 1 (2003): 2-3.
  56. Collie A., et al. “Computerised cognitive assessment of athletes with sports related head injury”. British Journal of Sports Medicine 5 (2001): 297-302.
  57. Eyres S., et al. “Construct validity and reliability of the Rivermead Post-Concussion Symptoms Questionnaire”. Clinical Rehabilitation 8 (2005): 878-887.
  58. Potter S., et al. “The rivermead post concussion symptoms questionnaire”. Journal of Neurology 12 (2006): 1603-1614.
  59. Montgomery SA and Asberg M. “A new depression scale designed to be sensitive to change”. British Journal of Psychiatry 134 (1979): 382-389.
  60. Bittencourt J., et al. “Saccadic eye movement applications for psychiatric disorders”. Neuropsychiatric Disease and Treatment 9 (2013): 1393.
  61. Rommelse NNJ., et al. “A review on eye movement studies in childhood and adolescent psychiatry”. Brain and Cognition 3 (2008): 391-414.
  62. Winograd-Gurvich C., et al. “Self-paced and reprogrammed saccades: differences between melancholic and non-melancholic depression”. Journal of Neuroscience Research 3 (2006): 253-260.
  63. Lithgow BJ., et al. “Quantitative separation of the depressive phase of bipolar disorder and major depressive disorder using electrovestibulography”. The World Journal of Biological Psychiatry (2019): 1-14.
  64. Lithgow BJ., et al. “Bipolar disorder in the balance”. European Archives of Psychiatry and Clinical Neuroscience (2018).
  65. Lithgow BJ., et al. “Major depression and electrovestibulography”. The World Journal of Biological Psychiatry 5 (2015): 334-350.
Citation: Behzad Mansouri., et al. “New Insight into Correlation between Convergence Insufficiency/Vestibular Abnormalities and Depression in Post-Concussion Syndrome”. EC Ophthalmology 11.7 (2020): 73-81.

PubMed Indexed Article

EC Pharmacology and Toxicology
LC-UV-MS and MS/MS Characterize Glutathione Reactivity with Different Isomers (2,2' and 2,4' vs. 4,4') of Methylene Diphenyl-Diisocyanate.

PMID: 31143884 [PubMed]

PMCID: PMC6536005

EC Pharmacology and Toxicology
Alzheimer's Pathogenesis, Metal-Mediated Redox Stress, and Potential Nanotheranostics.

PMID: 31565701 [PubMed]

PMCID: PMC6764777

EC Neurology
Differences in Rate of Cognitive Decline and Caregiver Burden between Alzheimer's Disease and Vascular Dementia: a Retrospective Study.

PMID: 27747317 [PubMed]

PMCID: PMC5065347

EC Pharmacology and Toxicology
Will Blockchain Technology Transform Healthcare and Biomedical Sciences?

PMID: 31460519 [PubMed]

PMCID: PMC6711478

EC Pharmacology and Toxicology
Is it a Prime Time for AI-powered Virtual Drug Screening?

PMID: 30215059 [PubMed]

PMCID: PMC6133253

EC Psychology and Psychiatry
Analysis of Evidence for the Combination of Pro-dopamine Regulator (KB220PAM) and Naltrexone to Prevent Opioid Use Disorder Relapse.

PMID: 30417173 [PubMed]

PMCID: PMC6226033

EC Anaesthesia
Arrest Under Anesthesia - What was the Culprit? A Case Report.

PMID: 30264037 [PubMed]

PMCID: PMC6155992

EC Orthopaedics
Distraction Implantation. A New Technique in Total Joint Arthroplasty and Direct Skeletal Attachment.

PMID: 30198026 [PubMed]

PMCID: PMC6124505

EC Pulmonology and Respiratory Medicine
Prevalence and factors associated with self-reported chronic obstructive pulmonary disease among adults aged 40-79: the National Health and Nutrition Examination Survey (NHANES) 2007-2012.

PMID: 30294723 [PubMed]

PMCID: PMC6169793

EC Dental Science
Important Dental Fiber-Reinforced Composite Molding Compound Breakthroughs

PMID: 29285526 [PubMed]

PMCID: PMC5743211

EC Microbiology
Prevalence of Intestinal Parasites Among HIV Infected and HIV Uninfected Patients Treated at the 1o De Maio Health Centre in Maputo, Mozambique

PMID: 29911204 [PubMed]

PMCID: PMC5999047

EC Microbiology
Macrophages and the Viral Dissemination Super Highway

PMID: 26949751 [PubMed]

PMCID: PMC4774560

EC Microbiology
The Microbiome, Antibiotics, and Health of the Pediatric Population.

PMID: 27390782 [PubMed]

PMCID: PMC4933318

EC Microbiology
Reactive Oxygen Species in HIV Infection

PMID: 28580453 [PubMed]

PMCID: PMC5450819

EC Microbiology
A Review of the CD4 T Cell Contribution to Lung Infection, Inflammation and Repair with a Focus on Wheeze and Asthma in the Pediatric Population

PMID: 26280024 [PubMed]

PMCID: PMC4533840

EC Neurology
Identifying Key Symptoms Differentiating Myalgic Encephalomyelitis and Chronic Fatigue Syndrome from Multiple Sclerosis

PMID: 28066845 [PubMed]

PMCID: PMC5214344

EC Pharmacology and Toxicology
Paradigm Shift is the Normal State of Pharmacology

PMID: 28936490 [PubMed]

PMCID: PMC5604476

EC Neurology
Examining those Meeting IOM Criteria Versus IOM Plus Fibromyalgia

PMID: 28713879 [PubMed]

PMCID: PMC5510658

EC Neurology
Unilateral Frontosphenoid Craniosynostosis: Case Report and a Review of the Literature

PMID: 28133641 [PubMed]

PMCID: PMC5267489

EC Ophthalmology
OCT-Angiography for Non-Invasive Monitoring of Neuronal and Vascular Structure in Mouse Retina: Implication for Characterization of Retinal Neurovascular Coupling

PMID: 29333536 [PubMed]

PMCID: PMC5766278

EC Neurology
Longer Duration of Downslope Treadmill Walking Induces Depression of H-Reflexes Measured during Standing and Walking.

PMID: 31032493 [PubMed]

PMCID: PMC6483108

EC Microbiology
Onchocerciasis in Mozambique: An Unknown Condition for Health Professionals.

PMID: 30957099 [PubMed]

PMCID: PMC6448571

EC Nutrition
Food Insecurity among Households with and without Podoconiosis in East and West Gojjam, Ethiopia.

PMID: 30101228 [PubMed]

PMCID: PMC6086333

EC Ophthalmology
REVIEW. +2 to +3 D. Reading Glasses to Prevent Myopia.

PMID: 31080964 [PubMed]

PMCID: PMC6508883

EC Gynaecology
Biomechanical Mapping of the Female Pelvic Floor: Uterine Prolapse Versus Normal Conditions.

PMID: 31093608 [PubMed]

PMCID: PMC6513001

EC Dental Science
Fiber-Reinforced Composites: A Breakthrough in Practical Clinical Applications with Advanced Wear Resistance for Dental Materials.

PMID: 31552397 [PubMed]

PMCID: PMC6758937

EC Microbiology
Neurocysticercosis in Child Bearing Women: An Overlooked Condition in Mozambique and a Potentially Missed Diagnosis in Women Presenting with Eclampsia.

PMID: 31681909 [PubMed]

PMCID: PMC6824723

EC Microbiology
Molecular Detection of Leptospira spp. in Rodents Trapped in the Mozambique Island City, Nampula Province, Mozambique.

PMID: 31681910 [PubMed]

PMCID: PMC6824726

EC Neurology
Endoplasmic Reticulum-Mitochondrial Cross-Talk in Neurodegenerative and Eye Diseases.

PMID: 31528859 [PubMed]

PMCID: PMC6746603

EC Psychology and Psychiatry
Can Chronic Consumption of Caffeine by Increasing D2/D3 Receptors Offer Benefit to Carriers of the DRD2 A1 Allele in Cocaine Abuse?

PMID: 31276119 [PubMed]

PMCID: PMC6604646

EC Anaesthesia
Real Time Locating Systems and sustainability of Perioperative Efficiency of Anesthesiologists.

PMID: 31406965 [PubMed]

PMCID: PMC6690616

EC Pharmacology and Toxicology
A Pilot STEM Curriculum Designed to Teach High School Students Concepts in Biochemical Engineering and Pharmacology.

PMID: 31517314 [PubMed]

PMCID: PMC6741290

EC Pharmacology and Toxicology
Toxic Mechanisms Underlying Motor Activity Changes Induced by a Mixture of Lead, Arsenic and Manganese.

PMID: 31633124 [PubMed]

PMCID: PMC6800226

EC Neurology
Research Volunteers' Attitudes Toward Chronic Fatigue Syndrome and Myalgic Encephalomyelitis.

PMID: 29662969 [PubMed]

PMCID: PMC5898812

EC Pharmacology and Toxicology
Hyperbaric Oxygen Therapy for Alzheimer's Disease.

PMID: 30215058 [PubMed]

PMCID: PMC6133268

News and Events

February Issue Release

We always feel pleasure to share our updates with you all. Here, notifying you that we have successfully released the February issue of respective journals and the latest articles can be viewed on the current issue pages.

Submission Deadline for Upcoming Issue

ECronicon delightfully welcomes all the authors around the globe for effective collaboration with an article submission for the upcoming issue of respective journals. Submissions are accepted on/before February 23, 2023.

Certificate of Publication

ECronicon honors with a "Publication Certificate" to the corresponding author by including the names of co-authors as a token of appreciation for publishing the work with our respective journals.

Best Article of the Issue

Editors of respective journals will always be very much interested in electing one Best Article after each issue release. The authors of the selected article will be honored with a "Best Article of the Issue" certificate.

Certifying for Review

ECronicon certifies the Editors for their first review done towards the assigned article of the respective journals.

Latest Articles

The latest articles will be updated immediately on the articles in press page of the respective journals.