Neuropsychologia 43 (2005) 1529–1545
A transfer appropriate processing approach to investigating implicit
memory for emotional words in the cerebral hemispheres
Marjorie A. Collins
, Amanda Cooke
School of Psychology, Murdoch University, Murdoch, Perth, WA 6150, Australia
Received 12 April 2004; received in revised form 1 October 2004; accepted 9 November 2004
Available online 16 February 2005
Forty undergraduate students participated in two experiments designed to investigate the impact of perceptual and conceptual encoding
manipulations on implicit memory for emotional words in each cerebral hemisphere. Adopting a transfer appropriate processing approach, the
encoding manipulations were designed to promote processing of the surface features of stimuli in Experiment 1, and their semantic meaning
in Experiment 2. In both experiments, participants completed the designated encoding task, followed by a lexical decision task where primed
and unprimed words were presented to the left (LVF) and right visual ﬁelds (RVF). In Experiment 1, implicit memory was observed for RVF
presentations of words primed according to their perceptual features. Word valence did not impact on visual ﬁeld of presentation for primed
or unprimed words. In Experiment 2, participation in the conceptual encoding task differentially impacted on processing and implicit memory
for emotional words presented in the LVF, where priming the conceptual meaning of words facilitated the processing of positive, relative to
negativeand non-emotional words. In addition, implicit memory for conceptually primed negative words was reﬂected in inhibition of primed
relativetounprimednegativelyvalencedwords presentedinthe LVF.In contrast, forRVF presentations,therewasevidenceofimplicit memory
for conceptually primed non-emotional words, but not for emotional words. The results are generally consistent with the right hemisphere
model of emotion, which posits greater right hemisphere involvement in both the processing and implicit memory of emotional stimuli. The
results also support Nagae and Moscovitch’s suggestion [Nagae, S., & Moscovitch, M. (2002). Cerebral hemispheric differences in memory
of emotional and non-emotional words in normal individuals.Neuropsychologia, 40, 1601–1607] that level of processing be incorporated into
studies examining the veracity of the right hemisphere and valence models of emotional processing. The study demonstrated the usefulness
of adopting a transfer appropriate processing approach to investigating memory for word valence in each hemisphere.
© 2005 Elsevier Ltd. All rights reserved.
Keywords: Right hemisphere model;Valence model;Implicit memory; Emotionalmemory; Transfer appropriateprocessing; Perceptual processing;Conceptual
processing; Cerebral hemispheres
Understanding the contribution of each cerebral hemi-
sphere to memory of emotional material has the potential to
pinning the formation and maintenance of cognitive biases
in anxiety and depression. It is clear that the emotionality
of a word inﬂuences both perception and memory of that
word. Explicit recall is enhanced for emotionally valenced
words relative to non-emotional words (Bock, 1986), recall
Corresponding author. Tel.: +61 8 9360 2858.
E-mail address: firstname.lastname@example.org (M.A. Collins).
is superior for positively valencedstimuli relative to negative
stimuli (Cacioppo, Petty, & Morris, 1985; Riskind & Lane,
1987) and implicit biases in processing emotional informa-
tion are evident in both clinical and non-clinical groups (e.g.
Denny & Hunt, 1992; Hocking & Collins, in press; Williams
& McDowell, 2001; Williams,Watts, MacLeod, & Mathews,
1997). It is also clear that there are hemispheric differences
in the processing of emotional words (e.g. Borod et al., 1998;
Kinsbourne & Bemporad, 1984). However, little is known
about the role each hemisphere plays in memory of emo-
tional linguistic stimuli. The current study redresses this.
Clinical and experimental research has cohered to pro-
duce two major neuropsychological models of hemispheric
0028-3932/$ – see front matter © 2005 Elsevier Ltd. All rights reserved.