RiskoMedimorecChisholmKingstone_COGSCI_REVISION2OCT26

Natural Behavior RUNNING HEAD: NATURAL BEHAVIOR Rotating with Rotated Text: A Natural Behavior Approach to Investigating Cognitive Offloading Evan F Risko1 Srdan Medimorec2 Joseph Chisholm3 Alan Kingstone3 1.University of Memphis Arizona State University University of British Columbia This work was supported by a Natural Sciences and Engineering Research Council of Canada (NSERC) Postdoctoral Fellowship and a Killam Postdoctoral Fellowship to EFR and NSERC operating grants to AK Address correspondence to Evan F Risko, Psychology Department, University of Memphis, Memphis, Tennessee, 38152, United States Email: Natural Behavior efrisko@memphis.edu Abstract Determining how we use our body to support cognition represents an important part of understanding the embodied and embedded nature of cognition In the present investigation, we pursue this question in the context of a common perceptual task Specifically, we report a series of experiments investigating head tilt (i.e., external normalization) as a strategy in letter naming and reading stimuli that are upright or rotated We demonstrate that the frequency of this natural behavior is modulated by the cost of stimulus rotation on performance In addition, we demonstrate that external normalization can benefit performance All of the results are consistent with the notion that external normalization represents a form of cognitive offloading and that effort is an important factor in the decision to adopt an internal or external strategy Natural Behavior Rotating with Rotated Text: A Natural Behavior Approach to Investigating Cognitive Offloading There is a growing emphasis in cognitive science on the embodied and embedded nature of cognition (e.g., Clark, 2010; Glenberg, 2010; Killen & Glenberg, 2010; Hollan, Hutchins, & Kirsh 2000; Hutchins, 1995; Kirsch, 1996; 2010; Pfieffer & Bongard, 2006; Wilson, 2002) According to this perspective, an important part of understanding cognition involves considering how we use our body (e.g., Pfiefer & Bongard, 2006) and the world (e.g., Kirsch, 1996) in the course of cognizing (Hutchins, 1995) In this conceptual framework the systematic study of naturally occurring behavior takes on added significance as it provides a window into the natural coupling between brain, body and world In the present investigation we apply a natural behavior approach to understanding how the cognitive system deals with impairments caused by stimulus rotation Understanding how individuals recognize objects that are not presented in their canonical orientation (i.e., rotated objects) has long represented a fundamental problem in cognitive psychology (e.g., Corballis, 1988; Graf, 2006; Jolicoeur, 1990a; Tarr, 1995; Tarr & Pinker, 1989) For example, presenting objects in a non-canonical orientation is often used in an attempt to understand constancies in visual object recognition (e.g., Tarr, 1995) There exist numerous demonstrations that performance, across a range of tasks, Natural Behavior can be impaired when stimuli are not presented in their canonical orientation (e.g., Corballis, 1988; Graf, 2006; Kung & Hamm, 2010; Jolicoeur, 1990a) This appears to be true for a number of different classes of stimuli and tasks, for example, naming line drawings of natural objects (Jolicoeur, 1985), naming single letters (Jolicoeur & Landau, 1984; Jolicoeur, Snow & Murray, 1987; Kolers & Perkins, 1969a; 1969b), reading words (Koriat & Norman, 1984), and recognizing scenes (Diwadkar & McNamara, 1997) That said, it is also important to note that presenting objects in a non-canonical orientation does not always lead to a cost (Hamm & McMullen, 1998; Murray, 1998; Wells & Hamm, 2009) When a cost occurs as a result of stimulus rotation it has typically been attributed to the need to engage in some form of (time consuming) mental transformation This mental transformation is thought to align the stimulus representation with a stored representation in memory Numerous accounts attribute this alignment to a form of analog mental rotation (e.g., Jolicoeur, 1990a; Tarr, 1995; Tarr & Pinker, 1989) Consistent with this idea are the similar patterns of performance found in studies of rotated object recognition and classic mental rotation (e.g., Cooper, 1975; Cooper & Shepard, 1975; Shepard, & Meltzer, 1971) However, numerous studies have questioned the notion that the cost associated with identifying a rotated object is due to the need to mentally rotate an internal representation of that object (Cheung, Hayward, & Gauthier, 2009; Gauthier, Hayward, Tarr, Anderson, Skudlarski, & Gore, 2002; Jolicoeur, Corballis, & Lawson, 1998; Wilson & Farah, 2006) An alternative account of the alignment process views it as a coordinate transformation (Graf, 2006) According to this account, alignment consists of the analog rotation of an internal reference frame to match the Natural Behavior stimulus The reference frame is considered to be viewer centered For example, when a rotated stimulus is presented this internal reference frame can be adjusted to match the orientation of the stimulus (e.g., top of the internal reference frame aligned with the top of the stimulus) in order to facilitate the matching of that representation to stored representations in memory Thus, in the coordinate transformation account, the representation of the stimulus is not rotated to be upright, but rather an internal reference frame is rotated to match the stimulus Some of the strongest evidence for the coordinate transformation account comes from research demonstrating orientation congruency effects wherein processing a stimulus at one orientation facilitates processing of another (unrelated) stimulus when their orientations are similar (Graf et al., 2005; Jolicoeur, 1990b; but see McMullen, Hamm, & Jolicoeur, 1995; Gauthier & Tarr, 1997) Because the present investigation is not concerned with discriminating between these accounts, we refer to the cost of stimulus rotation (when present) in a more neutral manner as resulting from some form of stimulus normalization, which would include mental rotation, frame alignment or any other similar procedure (Wells & Hamm, 2009) From Internal to External Normalization Normalization, whether via mental rotation or coordinate transformation, is considered an internal process However, an individual’s frame of reference can also be adjusted through external normalization (e.g., Koriat & Norman, 1984; Wexler, Kosslyn, & Berthoz, 1998) For example, Pashler, Ramachandran and Becker (2006) demonstrated that when an individual attends to a rotated word their eye will rotate in the direction of the tilt Thus, the body is aligned to some extent with the stimulus While this type of physical rotation is unlikely to compensate for much of the negative impact of stimulus Natural Behavior rotation, larger physical rotations, for example head tilt, certainly have that potential Indeed, as Wexler et al (1998) suggest, external forms of normalization may be the most common way individuals go about dealing with impairments caused by stimulus rotation Interestingly, the spontaneous use of this type of strategy has not come under systematic investigation Here we investigate one particular form of external normalization – head tilt While spontaneous head tilt in the context of tasks involving stimulus rotation has not been systematically studied, experimenter induced head tilt has been employed extensively (e.g., Corballis, Zbrodoff & Roldan, 1976; Corballis, Anuza & Blake, 1978; Corballis, Nagourney, Shetzer & Stefantos, 1978; McMullen & Jolicoeur, 1990; Rock & Heimer, 1957) In these experiments, participants are forced to adopt a particular degree of head tilt prior to the stimulus being presented in order to determine the coordinate frame used for object recognition This is because, when an individual’s head is upright and the stimulus is rotated, the performance cost that is observed is consistent with the use of either a retinal or a gravitational reference frame By forcing individuals to tilt their head prior to stimulus presentation; the use of these two reference frames can be disambiguated For example, if both the participant and the stimulus were rotated 60 degrees to the right, so that the stimulus is “upright” in retinal terms but “rotated” in gravitational terms, then a performance cost (relative to when the stimulus is presented at degrees) would provide evidence for the use of a gravitational coordinate frame Using such methods, McMullen and Jolicoeur (1990) demonstrated that naming objects uses a retinal reference frame Specifically, when participants’ head was tilted away from upright the function relating response time to angular deviation shifted in a manner Natural Behavior consistent with their physical tilt (i.e., response times were faster for objects that were tilted in the same direction as the participant) This is consistent with the idea that “upright” in naming objects is in retinal coordinates This result also provides evidence that spontaneous head tilt could, at least theoretically, facilitate performance by aligning the individual’s default frame of reference (i.e., upright in retinal coordinates) with the incoming stimulus In addition to the research on forced head tilt, the uses of external strategies in spatial visualization tasks that require the mental rotation of objects (rather than retrieving names or identities from memory) have also been investigated (Chandrasekharan, Athreya, & Srinivasan, 2010; Chu & Kita, 2008; 2010; Kirsh & Maglio, 1994; Maglio, Wenger, & Copeland, 2008) For example, Chu and Kita (2011) measured individual’s spontaneous use of gesture while performing a spatial visualization task involving mental rotation of three-dimensional objects They demonstrated that these gestures (e.g., rotating one’s hand) increased in frequency as the task became more difficult and that encouraging individuals to gesture while trying to solve the problem aided performance Chu and Kita (2011) suggested that these results could be attributed to gestures improving the internal computations involved in spatial visualization and/or gestures allowing individuals to offload demands for spatial working memory In the next section we explore further the notion of the latter mechanism (i.e., cognitive offloading) as a means of understanding spontaneous head tilt while individuals process rotated text Cognitive Offloading Head tilt while processing a rotated stimulus could be viewed as an alternative to internal normalization processes and as such an opportunity to offload cognitive work Natural Behavior The trading-off of internal processing (e.g., internal normalization processes) for external processing (e.g., head tilt) is referred to generally as cognitive offloading (e.g., Martin & Schwartz, 2005; Wilson, 2002) Understanding the tradeoff between internal and external processing is a fundamental question within the embodied and embedded cognition framework (Ballard et al., 1995; 1997; Carlson, Avramides, Cary & Strasberg, 2007; Cary & Carlson, 1999; 2001; Clark, 2010; Droll & Hayhoe, 2007; Gray & Boehm-Davis, 2000; Gray & Fu, 2004; Gray, Sims, Fu, & Schoelles, 2006; Kirsh, 2010; Wilson, 2002) To date, research investigating cognitive offloading has focused largely on the use of the world as a memory store (Ballard et al., 1995; 1997; Droll & Hayhoe, 2007; Gray & Boehm-Davis, 2000; Gray & Fu, 2004; Gray et al., 2006) In this case, the trade-off is between storing information internally (i.e., in-the-head) versus storing that information (or leaving that information) in an external location (i.e., in-the-world) For example, Gray and Fu (2004) had individuals program a virtual VCR with the program list (i.e., what they had to program into the VCR) available in the display (via an eye movement or other physical action) The question in this research addressed the extent to which individuals choose to store the program information in memory (i.e., in-the-head) versus leaving the information in the environment and retrieving it in a just-in-time fashion from the visual display We address a similar issue in the present investigation with respect to the tradeoff between internal and external normalization in letter naming and reading tasks The Natural Behavior Approach One of the attributes that make behaviors like head tilt in the context of, for example, reading a rotated paragraph interesting is that they emerge naturally in the Natural Behavior context of performing a cognitive task (Tunnel, 1977) The spontaneous nature of these behaviors, however, also makes them difficult to study using more traditional methods (Baumeister, Vohs, & Funder, 2007; Cialdini, 2009) Rather, understanding these natural behaviors requires supplementing traditional methodological approaches in cognitive psychology with more ethological (Tinbergen, 1963; Kingstone, Smilek & Eastwood, 2005; Risko & Kingstone, 2011) or ethnographic (Hutchins, 1995; Hollans et al., 2000) methods These approaches, through their emphasis on the observation and description of natural behavior, can provide a window into how individuals use their body and world to achieve their cognitive goals Specifically, by observing individuals in the midst of a particular cognitive act (e.g., trying to identify a rotated object) the potential use of the body (and the world) in that act become, so to speak, plain for the eye to see A critical feature of this approach is that the cognitive task is constrained but not the actions of the participant, thus allowing solutions to emerge that reveal the embodied and embedded nature of how we think In other words, a task environment needs to be created that permits these behaviors to emerge Subsequent studies can then constrain the behavior to further elucidate its function (e.g., Alibali, Spencer, Knox, & Kita, 2011; Carlson et al., 2007; Cary & Carlson, 1999; 2001; Chandrasekharan et al., 2010; Chu & Kita, 2008; 2011; Goldin-Meadow, Nusbaum, Kelly & Wagner, 2001) This general approach has been profitably applied in various areas (e.g., Ballard et al., 1995; Carlson et al., 2007; Cary & Carlson, 1999; 2001; Chu & Kita, 2008; 2011; Gray & Boehm-Davis, 2000; Gray & Fu, 2004; Gray et al., 2006; Hegarty & Steinhoff, 1997; Kirsh, 1995; Martin & Schwartz, 2005; Schwartz & Black, 1996; Risko & Kingstone, 2011; Vallee-Tourangeau & Wrightman, 2010), one of the most prominent of which is in the study of gesture (e.g., Natural Behavior 10 Alibali, Spencer, Knox, & Kita, 2011; Chu & Kita, 2008; 2011; Goldin-Meadow et al., 2001; Goldin-Meadow, 1999; 2005) In this case, a controlled setting is created that engages the cognitive act of interest (i.e., communicating through speech) and the behaviors that accompany speech (i.e., the gestures) are systematically observed and subjected to various manipulations (including restriction of the behavior) that elucidate their cognitive function In a similar vein, this approach can be likened to manipulating the presence of hard constraints (i.e., constraints that compel a particular strategy) to aid in the discovery of soft constraints (i.e., the factors that determine how individuals chose between different strategies; Gray & Fu, 2004) We apply this approach in the present investigation Present Investigation The purpose of the present investigation was to explore head tilt as a strategy in both letter naming and word reading tasks where the stimuli are presented (on some trials) in a non-canonical orientation We focus here on a number of critical issues including the amenability of the behavior to systematic investigation (Experiment and 3), the factors that influence its use (Experiments and 2), and the potential function of the behavior (Experiment 3) As noted above, one of the major issues to have arisen in research on cognitive offloading is how individuals decide whether to adopt an internal or external strategy One influential idea is that this decision is based on the relative effort each strategy requires The importance of effort as a determinant of choice behavior is well documented (e.g., Kool, McGuire, Rosen, & Botvinick, 2010; Payne, 1982; Payne, Bettman & Johnson, 1988) For example, according to Clark’s (2010) principle of ecological assembly individuals tend to “recruit, on the spot, whatever mix of problem- Natural Behavior 42 Glenberg, A M (2010) Embodiment as a unifying perspective for psychology Wiley Interdisciplinary Reviews: Cognitive Science, 1, 586-596 Goldin-Meadow, S., Nusbaum, H., Kelly, S D., & Wagner, S (2001) Explaining math: Gesturing lightens the load Psychological Science, 12, 516-522 Goldin-Meadow, S (2005) Hearing gesture: How our hands help us think Cambridge, MA: Harvard University Press Goldin-Meadow S (1999) The role of gesture in communication and thinking Trends in Cognitive Science, 13, 419-429 Graf, M (2006) Coordinate transformations in object recognition Psychological Bulletin, 132, 920– 945 Graf, M., Kaping, D & Bulthoff, H H (2005) Orientation congruency effects for familiar objects: Coordinate transformations in object recognition Psychological Science, 16, 214 – 221 Gray, W D., & Fu, W-T (2004) Soft constraints in interactive behavior: The case of ignoring perfect knowledge in-the-world for imperfect knowledge in-the-head Cognitive Science, 28, 359-382 Gray, W D., Sims, C R., Fu, W-T, & Schoelles, M J (2006) The soft constraints hypothesis: A rational analysis approach to resource allocation for interactive behavior Psychological Review, 113, 461-482 Gray, W D., & Boehm-Davis, D A (2000) Milliseconds Matter: An introduction to microstrategies and to their use in describing and predicting interactive behavior Journal of Experiment Psychology: Applied, 6, 322-335 Natural Behavior 43 Hamm, J P., & McMullen, P A (1998) Effects of Orientation on the Identification of Rotated Objects Depend on the Level of Identity Journal of Experimental Psychology: Human Perception and Performance, 24, 413-416 Hart, S G & Staveland, L E (1988) Development of NASA-TLX (Task Load Index): Results of empirical and theoretical research In P A Hancock and N Meshkati (Eds.) 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Canadian Journal of Experimental Psychology, 63, 33-39 Wexler, M., Kosslyn, S M & Berthoz, A (1998) Motor processes in mental rotation Cognition, 68, 77-94 Wilson, M (2002) Six views of embodied cognition Psychonomic Bulletin and Review, 9, 625-636 Wilson, K D., & Farah, M J (2006) Distinct patterns of viewpoint dependent BOLD activity during common-object recognition and mental rotation Perception,35, 1351–1366 Wohlschläger, A., & Wohlschlager, A (1998) Mental and manual rotation Journal of Experimental Psychology: Human Perception and Performance, 24, 397-412 Vallee-Tourangeau, T & Wrightman, M (2010) Interactive skills and individual differences in a word production task AI & Society, 25, 433-439 Natural Behavior 48 Table Mean percentage of trials individuals tilted, response time (in ms), and percentage of errors as a function of Set Size and Angular Deviation in Experiment Natural Behavior 49 % Head Tilt Angular Deviation Set Size 45 90 1.1 3.5 2.4 4.6 11.4 24.4 15 4.1 21.0 34.0 Response Time Angular Deviation Set Size 45 90 823 831 870 2023 2081 2499 15 5388 5568 5925 % Error Angular Deviation Set Size 45 90 0.0 0.0 0.7 4.1 5.5 9.6 15 10.0 11.7 8.8 Table Mean response time (in ms), and percentage of errors as a function of Set Size and Angular Deviation in Experiment Natural Behavior 50 Response Time Angular Deviation Set Size 45 90 963 1045 1068 2429 2436 2784 15 6174 6495 6797 % Error Angular Deviation Set Size 45 90 0.0 1.2 5.1 0.5 2.5 4.3 15 3.1 5.1 12.4 Table Mean response time (in ms) and average number of errors as a function of Angular Deviation and Condition in Experiment Natural Behavior 51 Response Time Angular Deviation Set Size 60 Free 18002 18689 Must Physically Rotate 18095 18490 No Physical Rotation 17881 19207 Errors Angular Deviation Set Size 60 Free 1.2 1.5 Must Physically Rotate 1.6 1.5 No Physical Rotation 1.4 1.5 Footnotes Natural Behavior 52 In order to address potential concerns about noise in the manual response RT was also determined using the vocal onset of the final letter (derived from video records) In Experiment the correlation between the manual RT and the RT determined using the vocal onset of the final word was r = 96 The results using the video based RTs were qualitatively similar to those generated using manual RT We provide this analysis for each experiment (see relevant sections of text) We conducted a parallel analysis on the vocal onset of the first letter in the array (derived from video records) in Experiment This analysis revealed a main effect of set size, F(1.61, 30.68) = 264.87, MSE = 25849.59, p < 05, ηp2 = 93, and angular deviation, F(1.36, 30.02) = 91.10, MSE = 9608.14, p < 05, ηp2 = 83, and an interaction between set size and angular deviation, F(2.91, 53.37) = 11.39, MSE = 12754.38, p < 05, ηp2 = 37 Participants’ vocal onset RT increased with increases in set size and angular deviation and the influence of the latter was greater in the and 15 letter conditions than in the letter condition In Experiment the correlation between the manual RT and the RT determined using the vocal onset of the final word (derived from video records) was r = 98 The results were qualitatively similar to those generated using manual RT We conducted a parallel analysis on the vocal onset of the first letter in the array (derived from video records) in Experiment This analysis revealed a main effect of set size, F(1.20, 22.85) = 97.37, MSE = 68015.88, p < 05, ηp2 = 84, and angular deviation, F(1.66, 31.55) = 101.92, MSE = 14227.51, p < 05, ηp2 = 62, and an interaction between set size and angular deviation, F(2.30, 43.67) = 3.32, MSE = 25244.32, p < 05, ηp2 = 15 Participants’ vocal onset RT increased with Natural Behavior 53 increases in set size and angular deviation and the influence of the latter was greater in the and 15 letter conditions than in the letter condition We also had a fourth condition that consisted of participants having to physically rotate to match the stimulus prior to it being presented This condition was counterbalanced with the other conditions but used a separate paragraph set, thus we did not include it in the analysis of Experiment The magnitude of the rotation effect in RT in this condition was consistent with what would be expected given the results reported in detail in the text (i.e., the effect was significantly smaller than in the STILL condition) In Experiment the correlation between the manual RT and the RT determined using the vocal onset of the final word (derived from video records) was r = 98 The results were qualitatively similar to those generated using manual RT Analysis of the vocal onset of the first word in the paragraph (derived from video records) revealed a main effect of condition, F(1.99, 45.77) = 4.07, MSE = 40502.88, p < 05, ηp2 = 15, and stimulus rotation, F(1, 23) = 101.92, MSE = 11276.08, p < 05, ηp2 = 82, but no interaction, F(1.87, 43.12) = 2.17, MSE = 12035.72, p = 12, ηp2 = 09 Participants responded fastest in the STILL condition and slowest in the FORCED ROTATION condition and slower on trials in which the stimulus was rotated than upright Natural Behavior 54 Figure Captions Example frames from participant video recordings Left Panel: Slopes relating percentage of trials individuals physically rotated to angular deviation (i.e., the higher the value the more likely participants were to physically rotate when the stimulus was rotated) for the three set sizes in Experiment and the paragraphs in Experiment (i.e., the FREE condition) Right Panel: Slopes relating response time (in ms) as a function of angular deviation (i.e., the higher the value the greater the cost when the stimulus was rotated) for the three set sizes in Experiment and the paragraphs in Experiment (i.e., the STILL condition) Natural Behavior 55 Natural Behavior 56 1.4 25 FreeRotation Conditions 1.2 Restricted Motion Conditions 20 15 0.8 0.6 10 0.4 0.2 0 Letter Letters Experiment 15 Letters Paragraph Experiment Letter Letters Experiment 15 Letters Paragraph Experiment ms/Degree %/Degree