Abstract
Neurologically normal individuals show an attentional bias toward the left side, which results from right hemisphere activation during visuospatial tasks. The strength of this bias is influenced by various factors, such as line length, vertical elevation and presentation time. What remains unknown is how participants gather information via saccadic eye movements during task performance and how this relates to their responses. Eye movements were recorded while participants performed the landmark task. Fixations and saccades were both analysed to gain a complete understanding of eye movement patterns. Fixations tended to focus on the centre of the line, with few left–right differences. Saccades were examined by creating histograms illustrating all x-coordinates which were examined over the course of each trial. Interestingly, mean eye position varied with participant response, with an overall tendency to look to the right of centre. Results are consistent with prior research, which has primarily looked at fixations and demonstrates the necessity of examining saccades as well as fixations in order to see how eye movement patterns relate to pseudoneglect.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Barrett AM, Crosson B, Crucian GP, Heilman KM (2000) Horizontal line bisections in upper and lower body space. J Int Neuropsych Soc 6:455–459. doi:10.1017/S135561770064403X
Barton JJS, Behrmann M, Black S (1998) Ocular search during line bisection: the effects of hemi-neglect and hemianopia. Brain 121:1117–1131. doi:10.1093/brain/121.6.1117
Bjoertomt O, Cowey A, Walsh V (2002) Spatial neglect in near and far space investigated by repetitive transcranial magnetic stimulation. Brain 125:2012–2022. doi:10.1093/brain/awf211
Bowers D, Heilman KM (1980) Pseudoneglect: effects of hemispace on a tactile line bisection task. Neuropsychologia 18:491–498. doi:10.1016/0028-3932(80)90151-7
Cavézian C, Valadao D, Hurwitz M, Saoud M, Danckert J (2012) Finding centre: ocular and fMRI investigations of bisection and landmark task performance. Brain Res 1437:89–103. doi:10.1016/j.brainres.2011.12.002
Çiçek M, Deouell LY, Knight RT (2009) Brain activity during landmark and line bisection tasks. Front Hum Neurosci 3:1–8. doi:10.3389/neuro.09.007.2009
Corbetta M, Shulman GL, Miezin FM, Petersen SE (1995) Superior parietal cortex activation during spatial attention shifts and visual feature conjunction. Science 270:802–805. doi:10.1126/science.270.5237.802
Demeyer M, De Graef P, Wagemans J, Verfaillie K (2010) Object form discontinuity facilitates displacement discrimination across saccades. J Vis 10:1–14. doi:10.1167/10.6.17
Deubel H (2008) The time course of presaccadic attention shifts. Psychol Res 72:630–640. doi:10.1007/s00426-008-0165-3
Elias LJ, Robinson E, Saucier DM (2005) Rightward biases in free-viewing visual bisection tasks: implications for leftward responses biases on similar tasks. Brain Cogn 59:296–298. doi:10.1016/j.bandc.2004.02.021
Fink GR, Marshall JC, Shah NJ, Weiss PH, Halligan PW, Grosse-Ruyken M, Ziemons K, Zilles K, Freund HJ (2000) Line bisection judgments implicate right parietal cortex and cerebellum as assessed by fMRI. Neurology 54:1324–1331
Fink GR, Marshall JC, Weiss PH, Zilles K (2001) The neural basis of vertical and horizontal line bisection judgments: an fMRI study of normal volunteers. NeuroImage 14:S59–S67. doi:10.1006/nimg.2001.0819
Foxe JJ, McCourt ME, Javitt DC (2003) Right hemisphere control of visuospatial attention: line-bisection judgments evaluated with high-density electrical mapping and source analysis. NeuroImage 19:710–726. doi:10.1016/S1053-8119(03)00057-0
Goodale MA, Milner AD (1992) Separate visual pathways for perception and action. Trends Neurosci 15:20–25. doi:10.1016/0166-2236(92)90344-8
Greene CM, Robertson IH, Gill M, Bellgrove MA (2010) Dopaminergic genotype influences spatial bias in healthy adults. Neuropsychologia 48:2458–2464. doi:10.1016/j.neuropsychologia.2010.04.019
Guo K, Smith C, Powell K, Nicholls K (2012) Consistent left gaze bias in processing different facial cues. Psychol Res 76:263–269. doi:10.1007/s00426-011-0340-9
Halligan PW, Manning L, Marshall JC (1991) Hemispheric activation vs spatio-motor cueing in visual neglect: a case study. Neuropsychologia 29:165–176. doi:10.1016/0028-3932(91)90018-4
Heilman KM, Watson RT, Valenstein E (2003) Neglect and related disorders. In: Heilman KM, Valenstein E (eds) Clinical neuropsychology, 4th edn. Oxford University Press, New York, pp 296–346
Heywood S, Churcher J (1980) Structure of the visual array and saccadic latency implications for oculomotor control. Q J Exp Psychol 32:335–341. doi:10.1080/14640748008401169
Honda H, Findlay J (1992) The increase in saccade latencies to the lower visual field. Percept Psychophys 52:167–174
Hurwitz M, Valadao D, Danckert J (2011) Static versus dynamic judgments of spatial extent. Exp Brain Res 209:271–286. doi:10.1007/s00221-011-2539-9
Ibbotson M, Krekelberg B (2011) Visual perception and saccadic eye movements. Curr Opin Neurobiol 21:553–558. doi:10.1016/j.conb.2011.05.012
Ishiai S, Furukawa T, Tsukagoshi H (1989) Visuospatial processes of line bisection and the mechanisms underlying unilateral spatial neglect. Brain 112:1485–1502. doi:10.1093/brain/112.6.1485
Jewell G, McCourt ME (2000) Pseudoneglect: a review and meta-analysis of performance factors in line bisection tasks. Neuropsychologia 38:93–110. doi:10.1016/S0028-3932(99)00045-7
Johns M, Crowley K, Chapman R, Tucker A, Hocking C (2009) The effect of blinks and saccadic eye movements on visual reaction times. Atten Psychophys 71:783–785. doi:10.3758/APP.71.4.783
Kinsbourne M (1970) The cerebral basis of lateral asymmetries in attention. Acta Psychol 33:193–201. doi:10.1016/0001-6918(70)90132-0
Kinsbourne M (1987) Mechanisms of unilateral neglect. In: Jeannerod M (ed) Neurophysiological and neuropsychological aspects of spatial neglect. Erlbaum, Hillsdale, pp 69–86
Kleiser R, Seitz RJ, Krekelberg B (2004) Neural correlates of saccadic suppression in humans. Curr Biol 14:386–390. doi:10.1016/j.cub.2004.02.036
Luh KE (1995) Line bisection and perceptual asymmetries in normal individuals: what you see is not what you get. Neuropsychology 9:435–448. doi:10.1037/0894-4105.9.4.435
McCourt ME (2001) Performance consistency of normal observers in forced-choice tachistoscopic visual line bisection. Neuropsychologia 39:1065–1076. doi:10.1016/S0028-3932(01)00044-6
McCourt ME, Garlinghouse M (2000) Asymmetries of visuospatial attention are modulated by viewing distance and visual field elevation: pseudoneglect in peripersonal and extrapersonal space. Cortex 36:715–731. doi:10.1016/S0010-9452(08)70548-3
McCourt ME, Jewell G (1999) Visuospatial attention in line bisection: Stimulus modulation of pseudoneglect. Neuropsychologia 37:843–855. doi:10.1016/S0028-3932(98)00140-7
McCourt ME, Garlinghouse M, Slater J (2000) Centripetal versus centrifugal bias in visual line bisection: focusing attention on two hypotheses. Front Biosci 5:D58–D71
Merkley R, Ansari D (2010) Using eye tracking to study numerical cognition: the case of the ratio effect. Exp Brain Res 206:455–460. doi:10.1007/s00221-010-2419-8
Nicholls MER, Bradshaw JL, Mattingley JB (1999) Free-viewing perceptual asymmetries for the judgement of brightness, numerosity and size. Neuropsychologia 37:307–314. doi:10.1016/S0028-3932(98)00074-8
Oldfield RC (1971) The assessment and analysis of handedness: the Edinburgh handedness inventory. Neuropsychologia 9:97–113. doi:10.1016/0028-3932(71)90067-4
Posner MI (1980) Orienting of attention. Q J Exp Psychol 32:3–25. doi:10.1080/00335558008248231
Posner MI, Rothbart MK (2007) Research on attention networks as a model for the integration of psychological science. Annu Rev Psychol 58:1–23. doi:10.1146/annurev.psych.58.110405.085516
Previc FH (1990) Functional specialization in the lower and upper visual fields in humans: its ecological origins and neurophysiological implications. Behav Brain Sci 13:519–575. doi:10.1017/S0140525X00080018
Rayner K (1998) Eye movements in reading and information processing: 20 years of research. Psychol Bull 124:372–422. doi:10.1037/0033-2909.124.3.372
Rueckert L, Dervanesian A, Baboorian D, Lacalamita A, Repplinger M (2002) Pseudoneglect and the cross-over effect. Neuropsychologia 40:162–173. doi:10.1016/S0028-3932(01)00082-3
Siman-Tov T, Mendelsohn A, Schonberg T, Avidan G, Podlipsky I, Pessoa L, Gadoth N, Ungerleider LG, Hendler T (2007) Bihemispheric leftward bias in a visuospatial attention-related network. J Neurosci 27:11271–11278. doi:10.1523/JNEUROSCI.0599-07.2007
Thiele A, Henning P, Kubischik M, Hoffmann KP (2002) Neural mechanisms of saccadic suppression. Science 295:2460–2462. doi:10.1126/science.1068788
Thomas NA, Elias LJ (2010) Do perceptual asymmetries differ in peripersonal and extrapersonal space? J Int Neuropsychol Soc 16:210–214. doi:10.1017/S135561770999097X
Thomas NA, Elias LJ (2011) Upper and lower visual field differences in perceptual asymmetries. Brain Res 1387:108–115. doi:10.1016/j.brainres.2011.02.063
Toba M, Cavanagh P, Bartolomeo P (2011) Attention biases the perceived midpoint of horizontal lines. Neuropsychologia 49:238–246. doi:10.1016/j.neuropsychologia.2010.11.022
Valadao DF, Hurwitz M, Danckert J (2010) Examining the influence of ‘noise’ on judgements of spatial extent. Exp Brain Res 207:157–164. doi:10.1007/s00221-010-2449-2
Acknowledgments
This research was supported by a Postdoctoral Fellowship to NAT from the Natural Sciences and Engineering Research Council. There are no relationships, financial or otherwise, that could be interpreted as a conflict of interest.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Thomas, N.A., Loetscher, T. & Nicholls, M.E.R. Central fixations with rightward deviations: saccadic eye movements on the landmark task. Exp Brain Res 220, 29–39 (2012). https://doi.org/10.1007/s00221-012-3113-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00221-012-3113-9