The Representation of Word Form and Location in Visual Cortex Lars Strother (
[email protected]), Alexandra M. Coros (
[email protected]) & Tutis Vilis (
[email protected])
Is there a ‘visual word form area’? Is there a visual word form area (VWFA) in left ventral occipitotemporal cortex (vOT)? [1,2]
Words > Objects in the VWFA? Left OFA? Left words
Right words
GOAL: Find an area that shows:
VWFA
Corpus callosum
Cohen et al. (2000)
Words > Fixation
(1) Adaptation to whole words [3,4]
V1-V4
V1-V4
FFA
LO
OFA
(2) Stronger fMRI responses to words than to objects -42, -58, -12 (±1)
(3) Position-invariant fMRI responses to words [1,5]
Whole-word adaptation in the VWFA? VWFA
Diff > Same OR Left REPEAT > Same
The VWFA and left OFA (but not LO) both respond more strongly to WORDS vs. OBJECTS.
Position sensitivity in left vOT
The VWFA was originally defined as position-invariant [1].
(WHITE)
(bias)
(bias)
VWFA (bias)
FFA
Right REPEAT > Same AND Left REPEAT > Same
Words were presented in one of five locations
LO OFA
This has recently been called into question [4].
(ORANGE)
Characteristics Whole-word adaptation
✓
✓
Words > Objects
✓
✓
Position Sensitivity All subjects showed adaptation in VWFA and also in more posterior vOT
VWFA Left OFA Left LO
✓
✓
The VWFA shows (1) whole-word adaptation and (2) words > objects. Left FFA does not.
✓
Left vOT is sensitive to word position.
✓
The VWFA and left OFA show wordselectivity but not position-invariance.
VWFA
Right words
Corpus callosum
The VWFA adapts to WHOLE WORDS but not to HALF WORDS.
Conclusions
Left words
OFA
V1-V4
V1-V4
[1] Cohen, L., Dehaene, S., Naccache, L., Lehericy, S., Lambertx, G., Henaff, M., Michel, F. (2000) Brain 123:291-307 [2] Price, C., and Devlin, T. (2003) NeuroImage 19:3 473-481 [3] Glezer, L., Jiang, X., Riesenhuber, M. (2009) Neuron 62: 199-204 [4] Molko, N., Cohen, L., Mangin, JF., Chochon, F., Lehericy, S., Le Bihan, D., Dehaene, S., (2002) JoCN [5] Rauschecker, A., Bowen, R., Parvisi, J., Wandell, B. (2012) PNAS