Psychological Science
2014, Vol. 25(1) 236­–242
© The Author(s) 2013
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DOI: 10.1177/0956797613498260
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Research Report
Spontaneous eye movements occur when people recall a
scene from memory, and recent research suggests that
such eye movements closely reflect the content and spatial
relations of the original scene (Johansson, Holsanova,
Dewhurst, & Holmqvist, 2012). However, the role of such
eye movements remains elusive. Do they have an active
and functional role facilitating the retrieval of visuospatial
information, or are they merely an epiphenomenon associated
with the operation of mnemonic mechanisms? In
the present study, we addressed this fundamental issue
using a direct manipulation of eye movement constraints
during an episodic memory task and found new evidence
of a facilitatory role of eye movements.
Episodic memory enables people to travel back in
time and re-experience previous events in great detail
(Tulving, 1983). Cognitive-neuroscience models of memory
suggest that such re-experiencing during retrieval is
based on the reinstatement of cortical processes that
were active at the time of the previous experience (e.g.,
Marr, 1971; Norman & O’Reilly, 2003). Accumulating evidence
supports this notion by demonstrating that common
neural systems are activated during perception and
retrieval (e.g., Nyberg, Habib, McIntosh, & Tulving, 2000;
Wheeler, Petersen, & Buckner, 2000; for reviews, see
Danker & Anderson, 2010; Kent & Lamberts, 2008; Rugg,
Johnson, Park, & Uncapher, 2008).
Episodic remembering is thought to depend on the
interaction between retrieval cues and stored memory
traces (Tulving, 1983). Two principles have been forwarded
to explain the effectiveness of the retrieval cues:
encoding specificity (Tulving & Thomson, 1973) and
transfer-appropriate processing (Morris, Bransford, &
Franks, 1977). According to both of these principles, the
greater the overlap between the processing engaged during
encoding and during retrieval, the greater the likelihood
of successful retrieval. The importance of the
compatibility between encoding and retrieval conditions
has been underscored by a vast body of memory research
(for a review, see Roediger & Guynn, 1996).
Thus, remembering involves the reinstatement of the
processes that were active during encoding, and the
chance of remembering is best when the processes
engaged by a retrieval cue overlap with those engaged at
498260PSSXXX10.1177/0956797613498260Johansson, JohanssonEye Movements and Memory Retrieval
research-article2013
Corresponding Author:
Roger Johansson, Department of Cognitive Science, Lund University,
Helgonabacken 12 223 62, Lund 223 62 Sweden
E-mail: roger.johansson@lucs.lu.se
Look Here, Eye Movements Play a
Functional Role in Memory Retrieval
Roger Johansson1
and Mikael Johansson2
1
Department of Cognitive Science, Lund University and 2
Department of Psychology, Lund University
Abstract
Research on episodic memory has established that spontaneous eye movements occur to spaces associated with
retrieved information even if those spaces are blank at the time of retrieval. Although it has been claimed that such
looks to “nothing” can function as facilitatory retrieval cues, there is currently no conclusive evidence for such an
effect. In the present study, we addressed this fundamental issue using four direct eye manipulations in the retrieval
phase of an episodic memory task: (a) free viewing on a blank screen, (b) maintaining central fixation, (c) looking
inside a square congruent with the location of the to-be-recalled objects, and (d) looking inside a square incongruent
with the location of the to-be-recalled objects. Our results provide novel evidence of an active and facilitatory role of
gaze position during memory retrieval and demonstrate that memory for the spatial relationship between objects is
more readily affected than memory for intrinsic object features.
Keywords
eye movements, episodic memory, memory, visual memory, visual attention
Received 3/13/13; Revision accepted 6/25/13
Eye Movements and Memory Retrieval	237
encoding. To what extent do these principles generalize
to the interplay between gaze behavior and memory
retrieval? Recent research suggests that recognition of
scenes and faces may improve when participants look at
the same features of the stimuli during study and during
test (Foulsham & Kingstone, 2013; Holm & Mäntylä, 2007;
Mäntylä & Holm, 2006). Remarkably, it has also been
shown that the oculomotor system reactivates spontaneously
during memory retrieval when there is only a blank
screen to look at (e.g., Brandt & Stark, 1997; Johansson,
Holsanova, & Holmqvist, 2006; Laeng & Teodorescu,
2002; Richardson & Spivey, 2000; Spivey & Geng, 2001).
Although it has been claimed that these eye movements
to “nothing” can act as facilitatory cues during memory
retrieval (cf. Ferreira, Apel, & Henderson, 2008; Richardson,
Altmann, Spivey, & Hoover, 2009), there is, to date, no
conclusive evidence for such a functional role.
In two previous studies, eye movements on a blank
screen were manipulated during episodic memory
retrieval by restricting gaze behavior to a central fixation
cross at the center of the screen. Both of these studies
showed impaired memory performance when gaze was
restricted compared with free viewing (Johansson et al.,
2012; Laeng & Teodorescu, 2002). However, it is possible
to attribute the lower performance in those cases to a
higher cognitive load due to the additional task of maintaining
gaze on the fixation cross (see Johansson et al.,
2012; Mast & Kosslyn, 2002). Moreover, a recent study
failed to reveal any consequence of eye position during
memory retrieval (Martarelli & Mast, 2013), and previous
studies without eye movement manipulations have failed
to find an influence of gaze position on retrieval accuracy
(Richardson & Spivey, 2000; Spivey & Geng, 2001). Thus,
the overall picture remains unclear.
The present study departs from previous research in
several ways. First, our paradigm imposed eye movement
restriction during visuospatial-memory retrieval of an
arrangement of multiple objects in both free-viewing and
central-fixation conditions. Previous studies have typically
focused on memory for visual properties of single
objects (Laeng & Teodorescu, 2002; Martarelli & Mast,
2013; Spivey & Geng, 2001) or on verbal memory for
spoken information (Richardson & Spivey, 2000). Second,
we considered the role of participants looking at a specific
location that did or did not correspond to (i.e., was
congruent or incongruent with) the location associated
with the sought-after memories. It has been argued that
eye movements function as “spatial indexes” and that
those indexes are a part of the internal memory representation
for an object or an event. When some part of this
episodic trace is accessed during subsequent memory
retrieval, an eye movement is thought to be spontaneously
triggered toward the indexed location (Altmann,
2004; Richardson & Spivey, 2000). We thus tested the idea
that positioning the eyes on a location congruent with
their location during encoding increases the likelihood of
successful retrieval.
Another way in which our study departed from previous
research is that we investigated the extent to which
interactions between eye movements and visuospatialmemory
retrieval depend on the nature of the queried
memory representation. Much evidence suggests that the
ventral (“what”) and dorsal (“how and where”) streams
of visual processing (Milner & Goodale, 1995; Ungerleider
& Mishkin, 1982) establish the bases for object and location
memory, respectively (e.g., Farah, Hammond, Levine,
& Calvanio, 1988; Pollatsek, Rayner, & Henderson, 1990).
It is conceivable that the influence of eye movements on
visuospatial remembering may be different for intrinsic
object features than for the spatial relationship between
two or more objects. This issue has not been examined
in previous work, and we therefore included a comparison
of memory for intrinsic object features with memory
for the spatial arrangement between objects (intra- vs.
interobject memories). Finally, in contrast to previous
work, our analyses of memory performance included
response times (RTs), which provide a complementary
and potentially more sensitive measure of the availability
of the sought-after memory trace than do binary measures
of accuracy (cf. Sternberg, 1969).
Given that gaze behavior has a functional role in
memory retrieval, we expected memory performance to
be superior (a) in the free-viewing than in the centralfixation
condition and (b) when fixation locations were
spatially congruent with the sought-after memory than
when they were spatially incongruent.
Method
Participants
Twenty-four native Swedish-speaking students at Lund
University (15 female, 9 male) participated in the study
(mean age = 24.5 years, SD = 7.1). All reported normal or
corrected-to-normal vision.
Apparatus and stimuli
Stimuli were presented using Experiment Center (Version
3.1; SensoMotoric Instruments, Teltow, Germany) on a
480- × 300-mm monitor (resolution = 1,680 × 1,050 pixels).
Eye movements were measured using an iView
RED500 eye tracker (SensoMotoric Instruments) that
recorded binocularly at 500 Hz. Data were recorded with
the iView X 2.5 software following five-point calibration
plus validation (average measured accuracy = 0.49°; SD =
0.10°). Fixations were detected with a saccadic-velocitybased
algorithm (minimum velocity threshold = 40°/s).
238	 R. Johansson, M. Johansson
Ninety-six pictures of objects (280 × 262 pixels) were
selected from an online database (www.clipart.com).
Auditory stimuli consisted of 576 statements (2,500–4,500
ms in length). The statements served as test probes (questions
with a yes/no answer) and were spoken by a female
voice.
Design and procedure
Data were obtained in four runs, each of which comprised
an encoding phase and a recall phase (see Fig. 1).
Encoding phase.  In the encoding phase, participants
studied 24 objects distributed in the four quadrants of the
computer screen. Each quadrant contained six objects
from one of four categories: humanoids, animals, things,
and vehicles. Half of the objects within each quadrant
were facing right, and the other half were facing left. The
encoding procedure was performed in the following
sequence. First, a list naming the 6 thematic objects of a
quadrant was presented. The objects were then visually
presented in one quadrant of the screen simultaneously
(30 s). Participants orally named each object and its orientation.
They were then free to inspect the objects and
try to remember as much as possible about their orientation
and spatial arrangement in the time allotted. The
same procedure was followed for the remaining quadrants
and themes, after which participants inspected all
24 objects simultaneously while rehearsing the objects’
orientation and spatial arrangement (60 s).
Recall phase.  In each condition of the recall phase,
participants listened to 48 statements of two types:
intraobject statements concerning the orientation of an
object (e.g., “the car was facing left”) and interobject
statements concerning the spatial arrangement between
two objects of the same category (e.g., “the train was
located to the right of the car”). Participants indicated
whether the statements were true or false by saying “yes”
or “no.” They were encouraged to answer as quickly and
as accurately as possible without guessing.
Participants responded to statements in four eye movement
conditions: (a) free viewing on a blank screen, (b)
central fixation, (c) looking inside a square congruent with
the location of the to-be-recalled objects, and (d) looking
inside a square incongruent with the location of the to-berecalled
objects. Twelve statements (6 intraobject, 6
interobject) were spoken in each condition. The free-viewing
and central-fixation conditions were presented in
blocked fashion, whereas the congruent and incongruent
trials were intermingled across two blocks. Participants
were not informed that the quadrant would be either congruent
or incongruent with the location of the target object.
Over the entire study, each participant responded to 192
statements (96 intraobject and 96 interobject); there were
an equal number of true and false statements. Participants
were given 8 s to respond following statement offset. The
order of intraobject and interobject statements and true
and false statements was randomized. The order of the
four eye movement conditions was counterbalanced in a
Latin square design within subjects over the four runs.
“Yes”/
“No”
2 s
8 s
Statement
+
+
+
Encoding Recall
Free Viewing
Response
Full Display of
Objects to Encode
Example Stimuli
in One Quadrant
+
Central Fixation Congruent/Incongruent
Fig. 1.  Diagram showing the two phases of the study. In the encoding phase, participants saw the names of 24 objects from four categories
and then saw the objects in each category displayed as a group; one group appeared in each quadrant of the computer screen. Half of the
objects within each quadrant faced right, and the other half faced left. In each condition of the recall phase, participants listened to 96 statements
of two types: intraobject statements concerning the direction in which the object was oriented and interobject statements concerning
the location of the object in relation to another object of the same category. Participants had to say whether each statement was true or false
by answering “yes” or “no.” Participants responded to these statements in four eye movement conditions: during free viewing, while fixating
on a central cross, while looking inside a square congruent with the location of the to-be-recalled object, and while looking inside a square
incongruent with the location of the to-be-recalled object.
Eye Movements and Memory Retrieval	239
The size of the square in the congruent and incongruent
condition was the same as the size of the individual
stimulus pictures. The location of the square in the incongruent
condition was always dislocated 840 pixels in the
horizontal dimension and 262 pixels in the vertical
dimension from the object indicated in the statement (the
maximum distance that could be implemented in a consistent
way for all 24 locations).
Data analyses
Repeated measures analyses of variance were conducted
using eye movement condition and statement type
(intraobject vs. interobject) as independent variables and
response accuracy and RTs as dependent variables.
Accuracy was quantified by subtracting the percentage of
false alarms from the percentage of hits (Snodgrass &
Corwin, 1988). RTs were quantified as the time between
the offset of a spoken statement and the onset of the
response. RTs were collapsed over all hits into a median
RT for each condition and participant. Trials in which
participants executed saccades more than 3° away from
the fixation cross or outside the square (3° away from the
center of the square) were excluded from analysis.
Results
Spontaneous eye movements to
“nothing”
Eye movement data from the free-viewing condition
were analyzed to assess where participants spontaneously
looked during memory retrieval (see Fig. 2). Results
revealed a main effect of quadrant, F(3, 69) = 27.186, p <
.001; η2
= .54, 95% confidence interval (CI) = [.37, .65].
Follow-up tests using Bonferroni correction showed that
the proportion of fixations was significantly higher to the
quadrant relevant to the memory task than to all the
other three quadrants (p < .001). There was no effect
involving statement type. These results replicate previous
findings (Richardson & Spivey, 2000; Spivey & Geng,
2001) and demonstrate that eye movements are reliably
executed toward empty locations where information was
previously encoded. Moreover, a paired samples t test
revealed that the overall gaze distance was significantly
longer during interobject than during intraobject trials,
t(23) = 2.348, p < .05; d = 0.48, 95% CI = [0.05, 0.90] (see
the Supplemental Material available online for further
details).
Constraining eye movements to a
central fixation cross
The hypothesis that memory performance is impaired
when one is not allowed to execute spontaneous eye
movements to “nothing” was tested by contrasting the
free-viewing and central-fixation conditions (Fig. 3a).
An analysis of response accuracy revealed a significant
main effect of statement type, F(1, 23) = 15.484, p < .01;
η2
= .40, 95% CI = [.11, .62], which was due to better performance
to interobject than to intraobject statements;
however, there was no reliable effect of eye movement
condition. A significant interaction between eye movement
condition and statement type was observed for RTs,
F(1, 23) = 10.296, p < .01; η2
= .31, 95% CI = [.04, .55].
Follow-up analyses revealed a detrimental effect of constraining
eye movements to the central fixation cross; this
effect was observed in prolonged RTs for interobject
statements, t(23) = 4.08, p < .001; d = 0.83, 95% CI = [0.36,
1.29]. No reliable difference in RTs for the free-viewing
and central-fixation conditions was found for intraobject
statements.
Constraining eye movements to a
congruent versus an incongruent
location
The final and crucial set of analyses concerned the impact
of constraining eye movements to a location that differed
in whether it corresponded with the encoding location of
the to-be-remembered information or did not (Fig. 3b).
An analysis of accuracy revealed that memory performance
was better for interobject than for intraobject
statements, F(1, 23) = 17.523, p < .001; η2
= .43, 95% CI =
[.13, .64]. More important, however, participants demonstrated
a reliable benefit of looking at a congruent location,
both in terms of accuracy, F(1, 23) = 13.443, p < .01;
η2
= .37, 95% CI = [.08, .60], and RTs, F(1, 23) = 14.809,
p < .001; η2
= .39, 95% CI = [.10, .62]. This pattern of
results lends new support to the notion of gaze position
0%
5%
10%
15%
20%
25%
30%
35%
40%
Critical First Second Third
MeanFixations
Quadrant
Fig. 2.  Mean percentage of fixations in the four quadrants of the screen
during the recall phase of the free-viewing condition. The quadrant
that corresponded with the original location of the retrieved objects
was coded as the critical quadrant, and the other three quadrants were
coded as the first through third in a clockwise direction. Error bars
represent standard errors.
240	 R. Johansson, M. Johansson
playing a functional role in memory retrieval. Furthermore,
given that the task was identical in the congruent and the
incongruent conditions (constraining eye movements to
a small space), these results cannot be explained as a
mere artifact of increased cognitive load induced by a
secondary task.
Discussion
In the present study, we employed multiple eye movement
conditions to examine the role of gaze behavior in
episodic memory retrieval. Taken together, our results
provide new evidence of a facilitatory influence of gaze
position during remembering.
First, it was demonstrated that hindering eye movements
can influence visuospatial remembering. A centralfixation
constraint perturbed retrieval performance (as
indicated by increased RTs) for interobject representations.
This finding adds weight to previous results (Johansson
et al., 2012; Laeng & Teodorescu, 2002) and further suggests
that the impact of eye movements on visuospatial
memory may differ depending on the nature of the memory
representation one is searching for. The results indicate
that memory for the spatial relationship between
.30
.35
.40
.45
.50
.55
.60
.65
.70
.75
.80
Intraobject Interobject
ResponseAccuracy
Free-Viewing Condition
Central-Fixation Condition
a
Statement Type
1,000
1,200
1,400
1,600
1,800
2,000
2,200
2,400
Intraobject Interobject
Intraobject Interobject
RT(ms)
Statement Type
.30
.35
.40
.45
.50
.55
.60
.65
.70
.75
.80
Intraobject Interobject
ResponseAccuracy
b
Congruent Condition
Incongruent Condition
Statement Type
1,000
1,200
1,400
1,600
1,800
2,000
2,200
2,400RT(ms)
Statement Type
Fig. 3.  Mean response accuracy (proportion of hits – proportion of false alarms; left column) and mean response
time (RT) for correct responses (right column) as a function of statement type and condition. Results are shown in
(a) for eye movement conditions in which participants heard statements during free viewing on a blank screen and
while maintaining central fixation. Results are shown in (b) for eye movement conditions in which participants heard
statements while looking inside a square congruent with the location of the to-be-recalled objects and looking inside
a square incongruent with the location of the to-be-recalled objects. Error bars represent standard errors.
Eye Movements and Memory Retrieval	241
objects is more readily affected than memory for intrinsic
object features.
Second, our results confirm that memory retrieval is
indeed facilitated when eye movements are manipulated
toward a blank area that corresponds with the original
location of the to-be-recalled object. Results were robust
both in respect to memory accuracy and RTs, and these
effects were evident irrespective of statement type.
Looking at a congruent location thus facilitated retrieval
of both intraobject and interobject memory representations.
It is important to note that this facilitatory effect
cannot be attributed to a difference in cognitive resources
taxed by the compared conditions (previous research—
in which only free viewing and central fixation were
compared—could not rule this out). This is because both
the congruent and incongruent conditions in our study
were characterized by identical eye movement constraints
(to look inside a square).
Experience in everyday life constantly reminds people
that their memories often are a subject of distortion. They
may misremember properties of past events and completely
fail to retrieve a desired fact or previous episode.
Distorted memories and inaccurate retrieval of this kind
often depend on insufficient retrieval cues. The present
study demonstrates that how and where eye movements
are launched provide important retrieval cues for visuospatial
remembering. Thus, we showed that remembering
is not only accompanied by eye movements that
mirror those associated with the retrieved content but
also that gaze positions showing a compatibility between
encoding and retrieval conditions increase the likelihood
of successful episodic remembering (cf. Tulving, 1983).
This is a novel finding that extends previous literature
and informs current theoretical models of episodic
memory.
Author Contributions
Data were collected and analyzed by R. Johansson. R. Johansson
and M. Johansson designed the research and wrote the manuscript.
Both authors approved the final version of the manuscript
for submission.
Acknowledgments
We extend special thanks to Richard Dewhurst for valuable
input on the experimental design.
Declaration of Conflicting Interests
The authors declared that they had no conflicts of interest with
respect to their authorship or the publication of this article.
Funding
This study was supported by the Linnaeus Center for Thinking
in Time: Cognition, Communication, and Learning (CCL) at
Lund University, which is funded by the Swedish Research
Council (Grant No. 349-2007-8695).
Supplemental Material	
Additional supporting information may be found at http://pss
.sagepub.com/content/by/supplemental-data
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