Induced Visual Motion and Illusory Arm Movement

2009 ◽  
Author(s):  
Michael F. Sherrick
Keyword(s):  
Visual Motion ◽  
Arm Movement

The human cortical areas V6 and V6A

2015 ◽  
Vol 32 ◽  
Author(s):  
SABRINA PITZALIS ◽  
PATRIZIA FATTORI ◽  
CLAUDIO GALLETTI
Keyword(s):  
Moving Objects ◽  
Visual Motion ◽  
Dynamic Condition ◽  
Arm Movement ◽  
Wide Field ◽  
Object Distance ◽  
Close Proximity ◽  
Retinotopic Organization ◽  
Evoked Activity ◽  
Self Motion

AbstractIn macaque, it has long been known since the late nineties that the medial parieto-occipital sulcus (POS) contains two regions, V6 and V6A, important for visual motion and action. While V6 is a retinotopically organized extrastriate area, V6A is a broadly retinotopically organized visuomotor area constituted by a ventral and dorsal subdivision (V6Av and V6Ad), both containing arm movement-related cells active during spatially directed reaching movements. In humans, these areas have been mapped only in recent years thanks to neuroimaging methods. In a series of brain mapping studies, by using a combination of functional magnetic resonance imaging methods such as wide-field retinotopy and task-evoked activity, we mapped human areas V6 (Pitzalis et al., 2006) and V6Av (Pitzalis et al., 2013d) retinotopically and defined human V6Ad functionally as a pointing-selective region situated anteriorly in the close proximity of V6Av (Tosoni et al., 2014). Like in macaque, human V6 is a motion area (e.g., Pitzalis et al., 2010, 2012, 2013a,b,c), while V6Av and V6Ad respond to pointing movements (Tosoni et al., 2014). The retinotopic organization (when present), anatomical position, neighbor relations, and functional properties of these three areas closely resemble those reported for macaque V6 (Galletti et al., 1996, 1999a), V6Av, and V6Ad (Galletti et al., 1999b; Gamberini et al., 2011). We suggest that information on objects in depth which are translating in space, because of the self-motion, is processed in V6 and conveyed to V6A for evaluating object distance in a dynamic condition such as that created by self-motion, so to orchestrate the eye and arm movements necessary to reach or avoid static and moving objects in the environment.

Misdirected visual motion: Mae and phi

1991 ◽  
Author(s):  
Eric J. Hiris ◽  
Robert H. Cormack ◽  
Randolph Blake
Keyword(s):  
Visual Motion

Case Report: Management of a Patient with mTBI and Vestibular Hypofunction with the Binasal Occlusion Technique

2018 ◽  
pp. 87-90
Keyword(s):  
Case Report ◽  
Visual Motion ◽  
Hand Movement ◽  
Motion Sensitivity ◽  
Vestibular Hypofunction ◽  
First Case ◽  
Neurological Exam ◽  
History Of ◽  
Occlusion Technique ◽  
Visual Vertigo

Background: Binasal Occlusion (BNO) is a clinical technique used by many neurorehabilitative optometrists in patients with mild traumatic brain injury (mTBI) and increased visual motion sensitivity (VMS) or visual vertigo. BNO is a technique in which partial occluders are added to the spectacle lenses to suppress the abnormal peripheral visual motion information. This technique helps in reducing VMS symptoms (i.e., nausea, dizziness, balance difficulty, visual confusion). Case Report: A 44-year-old AA female presented for a routine eye exam with a history of mTBI approximately 33 years ago. She was suffering from severe dizziness for the last two years that was adversely impacting her ADLs. The dizziness occurred in all body positions and all environments throughout the day. She was diagnosed with vestibular hypofunction and had undergone vestibular therapy but reported little improvement. Neurological exam revealed dizziness with both OKN drum and hand movement, especially in the left visual field. BNO technique resulted in immediate relief of her dizziness symptoms. Conclusion: To our knowledge, this is the first case that illustrates how the BNO technique in isolation can be beneficial for patients with mTBI and vestibular hypofunction. It demonstrates the success that BNO has in filtering abnormal peripheral visual motion in these patients.

Premorbid migraine history as a risk factor for vestibular and oculomotor baseline concussion assessment in pediatric athletes

2019 ◽  
Vol 23 (4) ◽  
pp. 465-470 ◽  
Author(s):  
Ryan N. Moran ◽  
Tracey Covassin ◽  
Jessica Wallace
Keyword(s):  
Risk Factor ◽  
Smooth Pursuit ◽  
Migraine Headache ◽  
Visual Motion ◽  
Assessment Tools ◽  
Motion Sensitivity ◽  
Ocular Reflex ◽  
Migraine Headaches ◽  
Vestibular Ocular Reflex ◽  
History Of

OBJECTIVEMigraine history has recently been identified as a risk factor for concussion and recovery. The authors performed a cross-sectional study examining baseline outcome measures on newly developed and implemented concussion assessment tools in pediatrics. The purpose of this study was to examine the effects of premorbid, diagnosed migraine headaches as a risk factor on vestibular and oculomotor baseline assessment in pediatric athletes.METHODSPediatric athletes between the ages of 8 and 14 years with a diagnosed history of migraine headache (n = 28) and matched controls without a history of diagnosed migraine headache (n = 28) were administered a baseline concussion assessment battery, consisting of the Vestibular/Ocular Motor Screening (VOMS), near point of convergence (NPC), and the King-Devick (K-D) tests. Between-groups comparisons were performed for vestibular symptoms and provocation scores on the VOMS (smooth pursuit, saccades, convergence, vestibular/ocular reflex, visual motion sensitivity), NPC (average distance), and K-D (time).RESULTSIndividuals diagnosed with migraine headaches reported greater VOMS smooth pursuit scores (p = 0.02), convergence scores (p = 0.04), vestibular ocular reflex scores (p value range 0.002–0.04), and visual motion sensitivity scores (p = 0.009). Differences were also observed on K-D oculomotor performance with worse times in those diagnosed with migraine headache (p = 0.02). No differences were reported on NPC distance (p = 0.06) or headache symptom reporting (p = 0.07) prior to the VOMS assessment.CONCLUSIONSPediatric athletes diagnosed with migraine headaches reported higher baseline symptom provocation scores on the VOMS. Athletes with migraine headaches also performed worse on the K-D test, further illustrating the influence of premorbid migraine headaches as a risk factor for elevated concussion assessment outcomes at baseline. Special consideration may be warranted for post-concussion assessment in athletes with migraine headaches.

Sign in / Sign up

Export Citation Format

Share Document