Abstract
The concept of perceptual memory refers to the neural and cognitive processes underlying the storage of specific stimulus features such as spatial frequency, orientation, shape, contrast, and color. Psychophysical studies of perceptual memory indicate that observers can retain visual information about the spatial frequency of Gabor patterns independent of the orientation with which they are presented. Compared to discrimination of gratings with the same orientation, reaction times to orthogonally oriented gratings, however, increase suggesting additional processing. Using event-related fMRI we examined the pattern of neural activation evoked when subjects discriminated the spatial frequency of Gabors presented with the same or orthogonal orientation. Blood-oxygen level dependent BOLD fMRI revealed significantly elevated bilateral activity in visual areas (V1, V2) when the gratings to be compared had an orthogonal orientation, compared to when they had the same orientation. These findings suggest that a change in an irrelevant stimulus dimension requires additional processing in primary and secondary visual areas. The finding that the task-irrelevant stimulus property (orientation) had no significant effect on the prefrontal and intraparietal cortex supports a model of working memory in which discrimination and retention of basic stimulus dimensions is based on low-level perceptual memory stores that are located at an early stage in the visual process. Our findings suggest that accessing different stores requires time and has higher metabolic costs.
Similar content being viewed by others
References
Bradley A, Skottun BC (1984) The effects of large orientation and spatial frequency differences on spatial discriminations. Vis Res 24:1889–1896
Brett M, Anton JL, Valabregue R, Poline JP (2002) Region of interest analysis using an SPM toolbox. Neuroimage 16:497
Boynton GM, Finney EM (2003) Orientation-specific adaptation in human visual cortex. J Neurosci 23:8781–8787
Cooper LA, Shepard RN (1973) Chronometric studies of the rotation of mental images. In: Chase WG (ed) Visual information processing. Academic Press, New York, pp 75–176
Cornette L, Dupont P, Bormans G, Mortelmans L, Orban GA (2001) Separate neural correlates for the mnemonic components of successive discrimination and working memory tasks. Cer Cor 1:59–72
DeValois RL, DeValois KK (1990) Spatial vision. Oxford University Press, Oxford
Farah MJ (1995) The neural basis of mental imagery. In: Gazzaniga MS (ed) The cognitive neurosciences. MIT Press, Cambridge, pp 963–975
Farah MJ, Hammond KM (1988) Mental rotation and orientation-invariant object recognition: dissociable processes. Cognition 29:29–46
Greenlee MW, Lang HJ, Mergner T, Seeger W (1995) Visual short-term memory of stimulus velocity in patients with unilateral posterior brain damage. J Neurosci 15:2287–2300
Greenlee MW, Magnussen S, Reinvang I (2000) Brain regions involved in spatial frequency discrimination: evidence from fMRI. Exp Brain Res 132:399–403
Grill-Spector K, Malach R (2001) fMR-adaptation: a tool for studying the functional properties of human cortical neurons. Acta Psychol 107:293–321
Hugdahl K, Thomson T, Ersland L (2006) Sex differences in visuo-spatial processing: an fMRI study of mental rotation. Neuropsychologia 44:1575–1583
Kosslyn SM, Alpert NM, Thompson WL, Maljkovic V, Weise SB, Chabris CF, Hamilton SE, Rauch SL, Buonanno FS (1993) Visual mental imagery activates topographically organized visual cortex: PET investigations. J Cogn Neurosci 5:263–287
Kourtzi Z, Huberle E (2005) Spatiotemporal characteristics of form analysis in the human visual cortex revealed by rapid event-related fMRI adaptation. Neuroimage 28:440–452
Krekelberg B, Boynton G, van Wezel JA (2006) Adaptation: from single cells to BOLD signals. Trends Neurosci 29:250–256
Luck SJ, Vogel EK (1997) The capacity of visual working memory for features and conjunctions. Nature 390:279–281
Maffei L, Fiorentini A (1977) Spatial frequency rows in the striate visual cortex. Vis Res 17:257–264
Magnussen S (2000) Low-level memory processes in vision. Trends Neurosci 23:247–251
Magnussen S, Greenlee MW (1999) The psychophysics of perceptual memory. Psychol Res 62:81–92
Magnussen S, Greenlee MW, Thomas JP (1996) Parallel processing in visual short-term memory. Exp Psychol Hum Percept Perform 22:202–212
Magnussen S, Idås E, Myhre SH (1998) Representation of orientation and spatial frequency in perception and memory: a choice reaction-time analysis. J Exp Psychol Hum Percept Perform 24:707–718
Marois R, Ivanoff J (2005) Capacity limits of information processing in the brain. Trens Cogn Sci 9:296–305
Pasternak T, Greenlee MW (2005) Working memory in primate sensory systems. Nat Rev Neurosci 6:97–107
Wilken P, Ma WJ (2004) A detection theory account of change detection. J Vis 4:1120–1135
Williams C (1974) The effect of an irrelevant dimension on “same-different” judgements of multi-dimensional stimuli. Quart J Exp Psychol 26:26–31
Xu Y, Chun MM (2006) Dissociable neural mechanisms supporting visual short-term memory for objects. Nature 440:91–95
Zeki S (1993) A vision of the brain. Blackwell, Oxford
Author information
Authors and Affiliations
Corresponding author
Additional information
Supported by: BMBF Project “Visuospatial Cognition” and Norwegian Research Council.
Rights and permissions
About this article
Cite this article
Baumann, O., Endestad, T., Magnussen, S. et al. Delayed discrimination of spatial frequency for gratings of different orientation: behavioral and fMRI evidence for low-level perceptual memory stores in early visual cortex. Exp Brain Res 188, 363–369 (2008). https://doi.org/10.1007/s00221-008-1366-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00221-008-1366-0