How Vision impacts Memory: The visual connection in the adult neurological population Alicia M. Reiser, MS OTR/L Physical Therapy at St. Luke’s

Vision and Visual Perception Rowe et al (2009) up to 92% stroke survivors had some visual impairment Visual Deficits can be mistaken as cognitive or physical deficits Vision Primary way we acquire information Alerts us to danger, pleasure Enables anticipatory actions Plans for situations and reactions Visual Perception “Applying cognitive concepts of space and form to understand the visual world by transforming raw data form the retina into cognitive concepts” Eye Sight vs. Vision: What’s the Difference?

Mary Warren’s visual hierarchy and the 4 circles of vision Magnacellular Parvocellular Ambient (peripheral) vision Focal vision Doesn’t go to occipital lobe occipital/temporal lobes Visual language processing visual spatial processing Directs motor movement of eyes/hands object identification Gross Motor fine motor Visual cognition Visual memory Pattern recognition Scanning Visual attention Oculomotor control, visual fields, visual acuity Centering: Where is it? Identify: What is it? VISION Antigravity: Where am I? Speech/auditory: What do I know about it? (Hillier and Kawar, 2013) (Warren, 1993)

What does the hierarchy mean? Visual cognition: ability to mentally manipulate visual info and integrate it with other sensory info to solve problems, form plans and make decisions (executive functioning) Visual memory: store and retrieve a mental image of object in the mind’s eye, apply new patterns to solve problems by comparison Pattern recognition: identify the salient features of an object in order to visually remember it (shape, color, texture). This determines if the memory is laid down. Frontal Lobe looks for as many attractors as possible- what makes an object different. CVA and TBIs tend to use more generic attractors. Scanning: the ability of the fovea to fixate and take in the environment in a sequential pattern by using saccades automatically by the brain stem and voluntarily by the frontal lobes. Reading is usually linear, non structured shape is circular.

Hierarchy: works together at all levels- think developmentally Visual attention: 3 step cognitive process (disengage, move and compare). Critical step in visual processing using both global and focal attentions Oculomotor control, visual fields, visual acuity: together allows for efficient conjugate movement, registering the entire scene and eyesight, including contrast. Oculomotor control provides perceptual stability, acuity provides clarity of detail and color, and field allows for awareness of objects in environment (Warren, 1993) Hierarchy: works together at all levels- think developmentally Following brain injury: Visual field, acuity, control and visual attention impacted OT screens for this deficits and identifies limitations in occupational performance (Warren, 2014) Oculomotor control affected by disruption of CN function or disruption of CNS control Exotropia, high exophoria, accommodative dysfunction (Blurry vision), convergence insufficiency (diploplia), low blink rate, spatial disorientation (the inability of a person to determine his true body position, motion, and altitude relative to his surroundings), poor fixation, irregular eye pursuit movements and unstable ambient vision Diploplia, illusion that objects are moving in the environment, poor concentration and attention, staring, poor visual memory, eye pain, neuromotor deficits including balance, coordination and postural control (Kane)

Team Introduction Neuro opthomologist: diagnose and prognose- what caused the impairment? Neuro or behavioral optomotrist: diagnose, prognose and interventions to improve Certified Vision Rehab Therapist: if vision is significantly impaired to teach blind tech Occupational Therapist: screen and identify strategies to improve occupational performance

Primary changes after brain injury: Visual field, visual acuity, oculomotor control, visual attention

ADL performance affected Reading Writing Employment Role of parent, child, spouse, worker Functional Directional Skills Driving Topographical orientation Personal space

Vision Screen Performed by OT

Screen for Acuity Deficits due to optic nerve damage or bilateral damage to the occipital lobe High Contrast Acuity: distance and near, low contrast Distance Snellen Chart Reading acuity chart Mars Chart, LeaNumbers Chart or Glass Test Glass test: clear glass water to within ½”, then black mug with milk to within ½”

Treating acuity dysfunction Clean glasses Check med side effects: seizure, spasticity Refer to optometrist/opthomologist for refraction update Improve accommodation Use contrast on stairs, with meals, in bathroom, minimize patterns and clutter, increase lighting, LED lighting, enlarged adaptive equipment, organize environment, simplify tasks, manage glare Electronic Magnifiers

Visual pathway to the brain Left honomonous hemianopsia Right hemianopsia Binasal occlusion Tunnel vision

Screen for Visual Field Deficits due to MCA, PCA (75% result in homonymous hemianopsia) or occipital lobe brain injury Diagnosed by opthamologist or optometrist, usually after 5 months Perimetry testing: central and peripheral, manual or computerized Confrontation test: shown unreliable Tangent Screen: results given in isopter, absolute scale or gray scale diagrams Visual Skills for Reading Test (Pepper), Telephone number copy Trail making test, clock drawing test, single letter cancellation test, line bisection test

Behaviors seen with HH Don’t cross visual midline therefore filling in the blanks with previous visual memories, safety imparied Scan slowly to affected side impacting rate of ADL completion Miss detail on blind side with reading, small detail tasks Reduced hand monitoring with function Decreased mobility: slowed, looks down, stops to search, gets lost Writing: drifts ADLS: driving, shopping, yard work, meal prep, money mgmt, communication, homemaking, self-care Reading: word recognition due to limited fovea previously 19 characters, unable to preplan saccade Right: affects saccade, can’t preplan next word Left: omits words, skips lines

Treating Hemianopsia Recovery rare after 6 months (Zhang, et al, 2006): Compensation is Key Computerized Light boards: Dynavision, Wii Laser pointer: flashlight tag Reading: Pre-Reading tasks to increase saccade length, large print familiar text, occupation based text. Maybe not bifocals Writing: illumination, contrast, bold lines and black pen “Scan the environment” tasks Wider head turns Increased head movement for scanning Faster rate of head movement Improved search pattern Wide scanning tasks Approach from the affected side during divided attention tasks Modify the environment Prisms from neuro optomotrist

Visual Attention Skills to attend: filter out, balance all perceptions, become salient, termination Monitor central field (cones- what is it?) and peripheral field (rods-where am I?) Constant communication through cortex, brainstem and cerebellum orchestrated by the frontal lobe Mass practice , experience and context can all improve recovery

Types of Attention Focused attention: responding to specific element Sustained attention: maintaining response over period of time Selective attention: free from distraction of environment Alternating attention: shift from one task to another Divided attention: simultaneous engagement in more than one task, multitasking

Neglect If vestibular cortex: pusher syndrome Due to deviation in normal search pattern Disorder in: spatial cognition No concept of space….no insight spatial orientation Left sided space doesn’t exist spatial exploration Difficulty crossing visual midline Difficult disengaging search pattern from right 80% result from damage in right parieto-temporal-frontal circuitry (Warren) If vestibular cortex: pusher syndrome

Behaviors Decreased ADLS: reading, WC mobs, driving Limited insight Decreased task initiation Decreased sustained attention Decreased working memory Perseverates Decreased alternating attention

Evaluation for Visual Attention Why is there inattention? Spatial bias Impaired conceptualization Non lateralized inattention Tests: Cancellation tests (assesses search pattern), Telephone number copy, Reading performance, Design Copy, Scan Board, ScanCourse, Dynavision, ADL observation Spatial bias: can’t initiate to left side Conceptualization: decreased response to cuing to fix it Inattention: no sustained attention, task initiation, search pattern # Copy: look for errors on left, can’t find errors, fast completion time Reading: look for start in middle of page, unaware makes no sense Scan Board: like King Devick

Search Patterns (Warren) Left Hemianopsia Hemi- inattention Abbreviated search pattern- omissions on left Pattern is organized Re-scanning to check accuracy Sustained attention measured by completion time appropriate Improves with cuing Abbreviated search pattern- omissions on left Pattern is random Revisitng on right Reduced sustained attention, shorter completion time Cue meaningless

Interventions for Visual Attention Modify Environment to support participation Decrease pattern, increase contrast, reduce glare, lighting Improve attention through language to assess performance, activity based Visual Scanning Training Focus on: Left to right, symmetrical scanning, completing search to left, observe detail, anticipate, rapidly shifting R v L Visuospatial Training Tablet

Treating Visual Attention Multimatrix tasks: categorization, spelling Shapes and grid tasks Pencil and Marsden ball tasks with patch Cognitive load tasks Go-no-go: flash pen light a number of times, hold fingers up how many seconds to wait, then pt taps table equal to amount of flashes

Treatment Meaningful occupations Salient tasks: babies, pets, family Multimatrix Game, Tracking Tube Refer to developmental or neuro optometrist for prisms, lenses Sensory Input: Incorporate auditory, visual (prisms or partial occlusion) and vestibular treatment with cognitive load

Oculomotor Impairment Caused by closed head injury, facial trauma, Cranial nerve trauma or Brainstem injury; damage to cortical areas that use eye movements to shift attention (Warren), PD, MS Saccades: bring taret to fovea after activated by attention, uses scan and search with quick movements Smooth pursuits: triggered by movement and hold a moving image on the fovea Cervical VOR Remember that eye movement is complex combination of cortical, brainstem and cerebellar control

Accomodative dysfunction Convergence insufficiency Treated by optometrist OT uses larger print or magnifiers Binocular insufficiency Convergence excess Divergence excess Divergence insufficiency 23 kinds of nystagmus Ocular dysmetria: over/under shoots with saccades, slows down identification

3 steps to accommodate Converge to target and stimulate photoreceptors Lens thickens to refract light Pupils constrict to reduce scatter of light

Behaviors Difficulty focusing, altered perception, disruption of balance OT cannot fix oculomotor dysfunction Modify and Adapt Manage condition until resolves Eliminate stress for improved ADLS Most clears up within 6 months (Park, Hwang, Yu, 2008)

Altered Perception Diploplia Acquired paralytic strabismus Doubled images Blurred images Ghosting images Distorted images Acquired paralytic strabismus Due to paralysis or weakness of CN 3,4,6

Cranial Nerve Review: CN 3 (Oculomotor nerve) lesion: exotropia, vertical or medial movements difficult, lateral diploplia, ptosis, dilated pupil, due to severe TBI CN 4 (Trochlear Nerve) lesion: bilateral lesions common, vertical diploplia near vision, head tilt contralateral side CN 5 (Abducens Nerve) lesion: esotropia, lateral diploplia for far vision

Screening for binocularity What and how to screen: What does it mean? Unilateral Cover test: phorias near and far Broch string: convergence, suppression near vs far, alignment, accommodation Red/Green Fusion test: suppression right vs left eye Near point of convergence Behaviors with phorias: headache, blurred vision Convergence insufficiency: poor recall of what read, decreased reading, look out window Convergence excess: love to read, get close to notes to write Suppression: poor sports skills Accommodative infacility: poor concentration, poor sustained attention

Screen for diploplia Screen if binocular or monocular diploplia Only when both eyes open: binocular diploplia Patching can be useful Even when one eye shut: Monocular diploplia patching doesn’t help: requires sx, vision rehab or prisms Screen where the diploplia is? Move eyes around from 12 to 6 to 12 Where is the double vision worse? Better? Tilt head right, left. Worse, better? Patching: complete occlusion Can lead to monocular vision, eye fatigue and strain Must alternate patch- poor pt compliance Decreased depth perception / increase fall risk Strengthen the oculomotor deficit Occlusion: Binasal occlusion forcing peripheral vision Nasal portion of dominant eye Need MD consent

Diploplia cont…. Prisms from optomotrist when peripheral or central nerve injury (Hilliar, 2014) Used with phorias to achieve fusion. Multimatrix games Fusion tasks with scanning Convergence activities Reading Broch string Pencil push ups Add an auditory component with a metronome Add a cognitive load by converging on every 3rd beat

Other Disturbances in Visual Perception Visual discrimination: ability to discriminate one thing from another allowing for pattern recognition Pattern recognition: spatial patterns (shape of the letter), sequential patterns (q is a spatial pattern in a sequence of letters to form a word) and movement patterns (magnocellular through gestures, expression) Behaviors include not recognizing patterns, sequences, difficulty with symbolic literacy, difficulty organizing space and time

Visual Memory Semantic Declarative Memory: info heard or read Episodic Declarative Memory: remembering what did or what happened Implicit Procedural Memory: long term memory for motor learning task (tying shoe, handwriting) Working Memory: metacognition…think while we are thinking! Reading, writing, lecture

Visual Imagery Manipulating images in minds eye

Perceptual Midline Shift Perceived midline of body is not the actual midline of the body Auditory Visual Vestibular Due to dysynchrony of sensory integration at midbrain with major contributions from ambient visual pathway causing poor sports performance, social insecurity and difficulty driving (Hillier and Kawar) Benefit from yoked prisms

Treating Tunnel Vision Bimanual circles Mimicking gross motor movements while fixated straight ahead Flashlight tag Scarf juggling

Therapeutic strategies after trauma Adapt: make plastic changes in the cerebellum and brainstem neuronal responses to head movement Decrease retinal slip/oscillopsia Improve postural control and gaze Decrease vertigo Use for those with unilateral lesions with high velocity head movement or central lesion Habituate: minimize sensitivity to aggravating stimuli Use for those with unilateral lesions causing asymmetry and visual vestibular mismatch Substitute: enhance visual and somatosensory cues to compensate Use for those with bilateral lesions and high velocity unilateral lesions with gaze stability and somatosensory training

References Hillier, Carl and Kawar, Mary. (continuing education PDP, 2013). Eyesight to Insight: Visual/Vestibular Assessment and Treatment. Pittsburgh, PA. Hillier, Rita and Tarbutton, Natalie. Vision Deficits following Stroke: Implications for Occupational Therapy Practice. OT Practice, 19 (21), 13-16 Lane, Kenneth (2012). Visual Attention in Children: Theories and Activities. SLACK Publishers, New York. Park, UC; Kim S. J.; Hwang, J. M. & Yu, Y. S. (2008). Clinical features and natural history of acquired third, fourth, and sixth cranial nerve palsy. Eye (Lond). 2008 May;22(5):691-6. Epub 2007 Feb 9. Rowe, F., Brand, D., Jackson, C. A., Price, A., ….Freeman, C. (2009). Visual impairment following stroke: Do stroke patients require visual assessments? Age and Ageing, 38, 188-193. Rummell, Errol. (2012, September 17). Vision Rehab for Hemianopsia: How VRT can improve vision loss from a neurological origin. Advance for Occupational Therapy Practitioners

Warren, Mary. (1993). A Hierarchical Model for Evaluation and Treatment of visual Perceptual Dysfunction in Adult Acquired Brain Injury, Part 1. AJOT, 47, 42-54. Warren, Mary. (continuing education vis ABILITIES Rehab Services, inc. 2014). Visual Processing Impairment I: Evaluation and Intervention for Adult Acquired Brain Injury. JFK Johnson Rehabilitation Institute, Edison, New Jersey. Zhang, X., Kadar, S., Lynn, M. J., Newman, N. J. & Bouisse, V. (2006). Homonymous he,ianopsia in strole. Journal of Neuro-opthomology, 26, 180-183.

Appendix

Eye Terms Mobility: the ability to move eyes full range Motility: skill with which the eyes move (smooth, slightly jerky, jerky) Pursuits: tracking of moving object with body still or stationary object with body moving Steady fixation: ability to keep eyes from moving off moving target Saccades: quick eye movement for scanning environment, reading (visual memory, comprehension based here)

Eye Terms Binocularity (teaming or alignment) Phoria “the tendency to” or weakness Orthophoria: tendency to stay in alignment Exophoria: tendency to drift out, therefore a shift inward when contralateral eye occluded Esophoria: tendency to drift in, therefore a shift outward when contralateral eye occluded Hyperphoria: tendency to drift upward, therefore a shift downward when contralateral eye occluded Results in intermittent diploplia REFERRAL to Dev/Neuro Optomotrist if eso or hyperphoric

Binocularity Tropia “is out of alignment” or paralyzed/ Strabismus Exotropia: eye is turned out Esotropia: eye turned in Hypertropia: eye turned up Cyclotropia: eye is rotated Results in constant diploplia of gaze Strabismus is acquired from TBI or developmental