Asymmetric transfer of the dynamic motion aftereffect between first- and second-order cues and among different second-order cues

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Journal of Vision (2007) 7(8):1, 1-12

Asymmetric transfer of the dynamic motion aftereffect
between first- and second-order cues and among
different second-order cues

School of Psychology, University of Birmingham,
Birmingham, UK 1Π^πΓl^≤l

School of Psychology, University of Nottingham,
Nottingham, UK

School of Psychology, University of Nottingham,
Nottingham, UK 1Π^αΓl^≤l

Recent work on motion processing has suggested a distinction between first-order cues (such as luminance modulation
[LM]) and second-order cues (such as local contrast modulation [CM]). We studied interactions between moving LM, CM,
and orientation modulation (OM) first comparing their spatial- and temporal-frequency sensitivity. We then tested for the
transfer of the dynamic motion aftereffect (dMAE) between the three cues, matched for visibility. Observers adapted to
moving, 0.5-c/deg horizontal modulations for 2 min (with 10 s top-ups). Relatively strong dMAEs were found when the
adaptation and test patterns were defined by the same cue (i.e., both LM, both CM, or both OM); these effects were tuned
for spatial frequency in the case of LM and CM. There was a partial transfer of the dMAE from LM to CM and OM; this
transferred effect seemed to lose its tuning. The aftereffect transferred well from CM to OM and retained its tuning. There
was little or no transfer from CM to LM or from OM to CM or LM. This asymmetric transfer of the dMAE between first- and
second-order cues and between the second-order cues suggests some degree of separation between the mechanisms that
process them.

Keywords: motion, aftereffect, first order, second order, luminance, contrast, orientation

Citation: Schofield, A. J., Ledgeway, T., & Hutchinson, C. V. (2007). Asymmetric transfer of the dynamic motion aftereffect
between first- and second-order cues and among different second-order cues. Journal of Vision, 7(8):1, 1-12,
http://journalofvision.org/7/8/1/, doi:10.1167/7.8.1.

Introduction

The human visual system is sensitive to motion conveyed
by a range of cues including luminance modulations (LM,
Movie 1; known as “first-order” or “Fourier” cues) and
some modulations of visual texture, including local contrast
(CM, Movie 2), orientation (OM, Movie 3), flicker rate, and
element length/size (collectively termed “second-order”
cues; Cavanagh & Mather, 1989). Chubb and Sperling
(1988) termed the second-order cues “non-Fourier” to
emphasize that, unlike first-order cues, they do not contain
Fourier energy at the modulation frequency (although many
examples do contain distinct energy peaks at other
frequencies; Fleet & Langley, 1994).

The detection of second-order motion seems to require
some form of nonlinear processing aside from the
squaring implicit in the standard motion energy model
(Adelson & Bergen, 1985) because this model followed
by linear processes such as averaging cannot detect the
direction of motion for CM stimuli (Benton & Johnston,
1997; Ledgeway & Hutchinson, 2006). The balance of
evidence suggests that first- and second-order motion are
detected, at least initially, by separate mechanisms (see
Baker, 1999; Lu & Sperling, 1995, 2001; Smith, 1994;
Sperling & Lu, 1998, for reviews). Accordingly, the filter-
rectify-filter (FRF) model (Wilson, Ferrera, & Yo, 1992)
proposes two mechanisms for motion detection: a standard
motion energy mechanism that detects first-order motion
and a parallel mechanism that is preceded by a nonlinear
operator (to demodulate second-order cues) sandwiched
between two filtering stages that exclude first-order
signals from the second-order channel.

In contrast to the two-mechanism view, Benton (2002),
Benton and Johnston (2001), Benton, Johnston, McOwan,
and Victor (2001), Johnston, McOwan, and Benton
(1999), and Johnston, McOwan, and Buxton (1992) have
shown that first- and second-order motion (defined by
CM) can be detected by a single mechanism that extracts
motion gradients. However, it can been shown that some
gradient models are equivalent to the energy model
provided that the opponent motion energy signal is
normalized by the amount of “static” energy in the
stimulus (Adelson & Bergen, 1986; Benton, 2004; Bruce,

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