Visual Evoked Potentials

1
Visual Evoked Potentials Visual Motor
Perception in Hearing Loss

• Esra Ozcebe 1 PhD, Erol Belgin 1 PhD,
• Meral Topçu2 MD, Ferhunde Öktem3 PhD,
• Bora Eldem4 MD, Seniz Özusta3 MS
• 1. Hacettepe University Faculty of Medicine,
  Department of Otorhinolaryngology,
• Section of Audiology and Speech Pathology,
  Ankara-Turkey
• 2. Hacettepe University Faculty of Medicine,
  Department of Pediatrics Section of Pediatric
  Neurology Ankara-Turkey
• 3. Hacettepe University Faculty of Medicine,
  Department of Child Psychiatry Ankara-Turkey
• 4. Hacettepe University Faculty of Medicine,
  Department of Ophthalmology Ankara-Turkey

2

• Visual and auditory abilities are the first two
  requirements, if one of these abilities is
  damaged, it requires that healthy one play major
  role in the individuals development and
  learning.

3

• For the children with hearing loss, the major
  sense is vision as well as the auditory ability
  left.
• Through the general population, visual impairment
  are encountered more frequently in hearing
  impaired individuals, compared to people without
  hearing loss.

4
Litareture Vision problems - children with
hearing loss
5

• If hearing impaired person have significantly
  vision problems, this problem can not be
  explained only with refraction problems.
• What about the rest of visual system?
• Visual attention
• Visual perception
• Visual processing
• CENTRAL VISUAL SYSTEM ?????

6

• Impairment of one sensory system influences the
  organization and functioning of the remaining
  senses.

7

• The perceptual deficit theory
• Deficit in one sensory system negatively affects
  the development of the remaining systems
• The perceptual compensation theory
• Impairment in one sensory system might cause
  compensatory proficiency in other sensory systems
• (Parasnis, 1983)

8
Visual perception and visual attention in people
with HL

• Some studies have demonstrated
• Superior
• Parasnis, 1983, Stivalet et al. 1998
• Equivalent
• Tharpe, Ashmead, Rothpletz, 2002
• Poorer
• Quittner, Smith, Osberger, Mitchell, Katz,
  1994 Rothpletz, Ashmead, Tharpe, 2003, Erden,
  Otman Tunay, 2004 Yucel Derim 2008

9

• Auditory deprivation from birth leads to
  compensatory changes within the visual system
  that enhance attentional processing of the
  peripheral visual field.
• Proksch Bavelier (2002)

10

• Visual peripheral field
• Processing of peripheral distractors Deaf
• Visual central field
• Processing of central distractors Deaf
• Proksch Bavelier (2002)
• Sustained attention Deaf
• Parasnis et al. (2003)

11

• The aim of the study was to investigate visual
  evoked potentials visual motor perception in
  children with severely-profoundly hearing loss

12
Participants In study group was consisted of 23
prelingual children with severely-profoundly
hearing loss and control group was consisted of
age and sex matched 23 children with normal
hearing.
METHODS
Mean age of children for study group is 9 years 4
months Mean age of children for control group is
9 years 5 months
13
The inclusion criteria-1

• -minimum 71dB ? (PTA) for auditory threshold of
  both ears in the audiological evaluation of the
  children for study group
• - Normal hearing acuity was defined by passing a
  pure tone audiometric screening test a 25 dB HL
  ISO for 500, 1000, 2000 and 4000 Hz bilaterally
  for control group
• Audiological examination was done for all
  participants.

14
The inclusion criteria-2

• No pathologic finding in the systemic and
  neurological examination
• Systemic and neurological examinations of the
  children have been carried out in the section of
  pediatric neurology.
• Normal visual ability of both groups
• The presence of refraction defect has been
  investigated in the department of ophthalmology.

15
The inclusion criteria-3

• Normal intelligence quotient (performance IQ)
• Wechsler Intelligence Scale for children Revised
  (WISC-R) performance section was used in order to
  determine performance IQ
• Similar SES
• All hearing impared children
• Attend the same deaf school
• Use TC
• Not amplified before 6 years old (auditory
  deprivation)

16
METHODS

• Procedures VEP
• For assessing the central visual function,
  electrophysiological measurements named visual
  evoked potentials (VEP) were used.
• VEPs provide a sensitive indication of abnormal
  conduction in the visual pathway.
• Abnormalities in the amplitude and waveform of
  the VEPs may also be caused by the loss of axons
  in the pathway.
• Walsh,Kane Butler, 2005

17
METHODS

• Procedures VEP
• VEP (ST 10 Sensör Medelec ER 94/a VEP) test
  applied while patient is in sit down position and
  the test room was darkened during the test.
• Children were made to sit 80 centimeters far from
  the monitor with a total view angle of 16 degree,
  50 minutes of the view angle of the squares to be
  evoked and 80 percent of contrast ratio in black
  and white squares was adjusted.

18
METHODS

• Procedures VEP
• Stimulus was applied as to make two variations in
  a second. Wave length potentials of 1-100Hz were
  recorded by the computer.
• Each of the eyes was tested separately by closing
  the other one.
• Stimulation was periodically repeated at 128 and
  its multiples and the average of the responses
  were taken.

19
METHODS

• Procedures VEP
• According to the 10- 20 international application
  system, reference electrode was placed on the
  frontal region and the recorder electrode was
  placed on the occipital region. The neutral
  electrode was placed randomly some where on the
  head.

20
METHODS

• Procedures VEP
• In the assessment of the VEP wave, P100 value
  marked as P1 that is the first positive wave was
  taken as a basis and recorded as latency.
• The normal distribution range of P1 value for
  this age group, (10710milisecends) is determined
  by the help of the measurements previously made
  on a great number of healthy children.

21
METHODS

• Procedure VEP
• The values that have been found above this limit
  (10710milisecends) assumed as pathologic.
• Additionally difference of latency between left
  and right eyes, which exceeds 5 milliseconds, is
  accepted to be pathologic.

22
METHODS

• Procedures Bender-Gestalt Test
• Bender Gestalt visual motor perception test in
  order to evaluate visual motor perception.
• Bender Visual Motor Gestalt Test can be defined
  as a psychological assessment instrument used in
  the evaluation of visual-motor functioning and
  visual perception skills in both children and
  adults.
• Test scores are used in the possible organic
  brain damage identification and the maturation
  degree of the nervous system.

23
METHODS

• Procedures Bender-Gestalt Test
• The Bender Gestalt Test is an individually
  conducted pencil and paper test
• Nine geometric figures are drawn in black.
• Examinee saw these figures one at a time then,
  the examinee was asked to copy the figure on a
  blank sheet of paper.
• Total error scores were compared with normative
  values.

24
METHODS

• Procedures Bender-Gestalt Test
• These scoring items classified into four groups
• Distortion
• Rotation
• Perseveration
• Integration
• Items are scored on their presence or absence.
  The total score is the number of items judged to
  be a defined error.

25
RESULTS - VEP
Results of the study revealed that VEP findings
were found to be pathological in the 26 of the
children severely-profoundly hearing loss.
(Fishers Exact Chi Square Test).
26
Latency (msn) N1 79.20 78.00 P1
98.40 99.60 N2 132 134 Amplitude
(mv) N1-N2 -9.80 -11.40 P1-P2 14.40 15.80
Latency (msn) N1 76.80 76.80 P1 127
127 N2 226 229 Amplitude (mv) N1-N2
-30.60 -34.40 P1-P2 33.00 34.40
27
Total number of error in Bender-Gestalt Test for
study and control group
RESULTS- BENDER-GESTALT
Total numbers of error were analysed with
Levenes t test for independent groups.
28
Bender-Gestalt
Pathologic Bender-Gestalt
29
RESULTS- BENDER-GESTALT

• The results of our study revealed that 60.8 of
  hearing impaired children has abnormal
  Bender-Gestalt findings (Pearson Chi Square Test)

30
RESULTS

• The cases with abnormal VEP recordings and the
  cases with pathological Bender-Gestalt finding
  compared for assessing if there is a relationship
  between these two tests.

31
VEP BENDER-GESTALT RELATION

• There is no statistically significant relation
  between two groups (Fishers Exact Chi Square
  Test, p0.34)
• However five of six cases with pathological VEP
  recordings had also pathological Bender-Gestalt
  finding (83.3).

32
DISCUSSION

• Visual evoked potentials and Bender- Gestalt
  findings were found abnormal in study group.
• Results of the study support the perceptual
  defiency theory

33
DISCUSSION VEP Studies
There are contradictory results reported in the
literature.
34
DISCUSSION Abnormal VEP findings

• There is evidence from animal and human studies
  to suggest at least some level of cross-modal
  reorganization from  one sensory modality when
  another modality is deprived of input
• Armstrong et al., 2002 Lee et al., 2001

35
DISCUSSION Abnormal VEP findings

• Prominent activity in the temporal cortex in
  response to visual stimuli, specifically in the
  auditory cortical regions.
• Finney et al. (2001)

36
DISCUSSION Abnormal VEP findings

• VEP study with deaf adults
• deaf poor readers have abnormal VEP
• Neurobiological evidence that developmental
  dyslexia exists within the deaf population and is
  associated with the same underlying magnocellular
  system deficit.
• Samar, Parasnis Berent (2002)

37
DISCUSSION Visual-motor perception studies
Our results are consistent with the previously
published data
38
Conclusions-1

• Detailed investigation techniques should be
  performed in children with HL
• VEP, may provide further information about
  underlying pathological conditions such as
  developmental dyslexia
• Visual-motor perceptions and skills related
  with other areas should be evaluated in detail

39
Conclusions-2

• Approppriate targets should be set for the
  educational programs
• Educational programs concerning the other areas
  where child requires further support, in addition
  to hearing and speech-language therapy, should be
  implemented

40

• THANK YOU
• Esra Özcebe PhD
• eozcebe_at_gmail.com

41
References

• Armitage, I.M., Burke, J.P., Buffin, J.T. (1995).
  Visual impairment in severe and profound
  sensorineural deafness. Arch Dis Child,
  73(1),53-6.
• Armstrong, B.A., Neville, H.J., Hillyard, S.A.,
  Mitchell, T.V. (2002). Auditory deprivation
  affects processing of motion, but not color.
  Brain Res. Cogn. Brain Res. 14, 422434.
• Bender, I (1938) A visual motor gestalt test and
  its clinical use. Research Monograph, 3, New
  York Orthopsychiatric Association.
• Chlubnová, J., Kremlácek, J., Kubová, Z., Kuba,
  M. (2005) Visual evoked potentials and event
  related potentials in congenitally deaf subjects.
  Physiol Res., 54(6), 577-83.
• Elango,S., Reddy, T.N., Shriwas, S.R. (1994)
  Ocular abnormalities in children from a Malaysian
  school for the deaf. Ann Trop Paediatr, 14(2),
  149-52
• Erden, Z., Otman, S., Tunay,V. (2004) Is visual
  perception of hearing-impaired children different
  from healthy children? Int J Pediat
  Otorhinolaryngol 68, 281285.
• Finney, E.M., Fine I., Dobkins KR. (2001) Visual
  stimuli activate auditory cortex in the deaf. Nat
  Neurosci, 4, 11711173.
• Hanioglu-Kargi ,S., Koksal, M., Tomac, S.,
  Ugurba, S.H., Alpay, A. (2003). Ophthalmologic
  abnormalities in children from a Turkish school
  for the deaf. Turk J Pediatr, 45(1), 39-42
• Horn, D.L. Fagan, M.K, Dillon, C.M, Pisoni,D.B,
  Richard T. Miyamoto, R.T. (2007) Visual-Motor
  Integration Skills of Prelingually Deaf Children
  Implications for Pediatric Cochlear Implantation
  Laryngoscope, 117, 20172025
• Koppitz, E. M. (1963) The Bender Gestalt Test for
  young children . New York Grune Stratton.
• Lee, D.S., Lee, J.S., Oh, S.H., Kim, S.K., Kim,
  J.W., Chung, J.K., Lee, M.C., Kim, C.S. (2001).
  Cross-modal plasticity and cochlear implants.
  Nature ,409, 149150.
• Mohindra, I.(1976) Vision profile of deaf
  children. Am J Optom Physiol Opt, 53(8)412-9.
• Neville, H. J., Schmidt, A., Kutas, M. (1983).
  Altered visual-evoked potentials in congenitally
  deaf adults. Brain Res, 266, 127-132.
• Ozer S. (2007) Turkish childrens Bender-Gestalt
  Test performance A pilot study and Preliminary
  norms. Perceptual and Motor Skills, 105, 872-882.

42

• Parasnis, I. (1983). Visual perceptual skills and
  deafness A research review. J Acad Rehabil
  Audiol, 16, 148-160.
• Parasnis, I., Samar, V.J., Berent, G.P. (2003).
  Deaf adults without attention deficit
  hyperactivity disorder display reduced perceptual
  sensitivity and elevated impulsivity on the Test
  of Variables of Attention (T.O.V.A.).J Speech
  Lang Hear Res. 46(5), 1166-83.
• Proksch, J., Bavelier, D. 2002 Changes in the
  spatial distribution of visual attention after
  early deafness, J Cogn Neurosci, 114(5), 687-701
• Quittner, A. L., Smith, L. B., Osberger, M. J.,
  Mitchell, T. V., Katz, D. B. (1994). The impact
  of audition on the development of visual
  attention. Psychological Science, 5, 347-353.
• Regenbogen, L., Godel, V. (1985) Ocular
  deficiencies in deaf children. J Pediatr
  Ophthalmol Strabismus,22(6),231-3
• Rettenbach, R.., Diller, G., Sireteanu, R. (1999)
  Do deaf people see better? Texture segmentation
  and visual search compensate in adult but not in
  juvenile subjects. J. Cogn. Neurosci. 11 5,
  60583
• Rothpletz, A., Ashmead, D. H., Tharpe, A. M.
  (2003). Responses to targets in the visual
  periphery in deaf and normal hearing adults. J
  Speech Lang Hear Res, 46, 269-280.
• Samar, V. J., Parasnis, I., Berent, G. P.
  (2002). Deaf poor readers pattern reversal
  visual evoked potentials suggest magnocellular
  system deficits Implications for diagnostic
  neuroimaging of dyslexia in deaf individuals.
  Brain Lang, 80, 2144.
• Siatkowski, R.M., Flynn, J.T., Hodges, A.V.,
  Balkany, T.J. (1994). Ophthalmologic
  abnormalities in the pediatric cochlear implant
  population. Am J Ophthalmol, 15118(1), 70-6.
• Stivalet, P., Moreno, Y., Richard, J., Barraud,
  P. A., Raphel, C. (1998). Differences in visual
  search tasks between congenitally deaf and normal
  hearing adults. Cogn Brain Res, 6, 227-232.
• Tharpe, A. M., Ashmead, D. H., Rothpletz, A. M.
  (2002). Visual attention in children with normal
  hearing, children with hearing aids, and children
  with cochlear implants. J Speech Lang Hear Res ,
  45, 103-113.
• Viegersma P.H., Van der Velde, A. (1983), Motor
  development of deaf children. J. Child Psychol.
  Psychiatr, 24 1, 103111.
• Walsh, P., Kane, N., Butler, S (2005) . The
  Clinical Role of Evoked Potentials J Neurol
  Neurosurg Psychiatry76(Suppl II)ii16ii22.
• Yucel, E., Derim, D.(2008) The effect of
  implantation age on visual attention skills. Int
  J Pediatr Otorhinolaryngol, 72(6), 869-77.