Described as a way for everyday urbanites to "re-explore their local area by walking the neighborhood" (Nold, "Bio Mapping," n.d.), Christian Nold’s Bio Mapping project offered participants the opportunity to re-imagine local spaces at the level of felt bodily sensation. Artistically and politically couched as a response to the proliferation of surveillance technologies, as well as the sense of "placeless dissociation" (Jameson, 1991, p. 42) that increasingly accompanies life in the networked society, Nold’s project argued "that we can re-embody ourselves in the world, thereby escaping the prevailing sense that our experience of place is disappearing in late capitalist society" (Tuters & Varnelis, 2008, para. 9). By appropriating mapping technologies and by working to foster community awareness of the ways spaces engage and are engaged by residents’ bodies and emotional attunements, Bio Mapping overlaps in interesting ways with Reynolds’s project and the emphasis it places on understanding the materiality of spatial practices.

At the same time, Bio Mapping also offers a slightly different take on one of the key questions Reynolds identified as informing her Mapping URI project, namely: "What are the limitations of a two-dimensional map of the campus in representing [students’] experiences as they move through different buildings, quadrangles, or parking lots?" (2004, p. 158). As we’ll see, even as it clearly intends to represent participants’ experiences as they move/d through space, Bio Mapping acknowledges a necessary and irreparable gap between the event of sensation and the representation of that event in speech and writing. And it’s precisely this gap, inherent in the act and artifact of writing and indicative of an irreconcilable impasse between memory and forgetting, that constitutes one of the most valuable contributions Bio Mapping can make to the development of spatial rhetorics and pedagogies going forward.

As Nold has commented in several places, Bio Mapping aims to challenge commonplace assumptions about space and about what it means, or ought to mean, to be a citizen-subject in the world. By appropriating and repurposing surveillance technologies and by inviting participants to "see" and interpret their own bodies in space, Bio Mapping poses a bold counterstatement to the prevailing wisdom of the modern surveillance society, which suggests that the interpretation of the data collected by devices such as polygraphs and CCTV cameras can only run one way, from the institutions of power, whose mission it is to know as much about us as they possibly can, rather than from our own (subjugated) bodies. In contrast to these assumptions, Bio Mapping asks instead:

What would happen if we could make use of intimate biological data derived from our own bodies? Instead of handing over our DNA, fingerprints or retina scans to an "expert" for interpretation, we could gather, interpret and share this information with whoever we choose. (Nold, "Leaflet," n.d., para. 1)

To explore these questions practically, Nold invented and built the Bio Mapping device, a portable and wearable tool that records data from two ubiquitous (and now easily accessible) surveillance technologies: a simple biometric sensor measuring Galvanic Skin Response (GSR) and a Global Positioning System (GPS). Emotion Map PeaksLike the polygraph or lie-detector test, the GSR sensors attached to participants’ fingertips record changing levels of sweat on the skin and fluctuations in the body’s internal temperature which indicate varying degrees of physiological arousal  ("Leaflet," n.d., para. 4). Coupled with the geographical locations recorded by the GPS, the GSR sensors allow users to measure moments of emotional intensity as they occurred at a given time and place—often during a one or two hour walk through the participant’s home city or neighborhood. Once uploaded to Nold’s custom-built mapping software (or, more recently, to Google Earth), these two data sources provided the raw material for generating what Nold called an "Emotion Map," a graphic representation of one person’s emotional responses during a brief walk in the city, with the tallest spikes, as pictured above, indicating those moments of highest arousal (e.g., fear, stress, excitement).

Of course, on their own, images—even those as engaging and suggestive as the ones generated by Nold’s software—can only explain so much about a participant’s emotional experiences in time and space. A crucial part of the emotion mapping process, therefore, occurs after the fact, in the moments when Nold invited the participant to read and interpret the data represented on his or her Emotion Map. Indeed, this interpretative step was for Nold a crucial part of Bio Mapping’s overall mission and political intervention. As Nold put it:

By allowing people to make active choices about how to share this intimate yet ambiguous data we not only create radically new social relations but we also change our own perception of ourselves from being at the mercy of these nearly invisible technical systems to becoming their master. ("Interrogating," n.d., para. 8)

By providing participants the opportunity to view, share, and interpret their own bio-data, Bio Mapping aims to give citizens the power to see and make sense of their individual bio-data. In this sense, Nold argued,

Bio Mapping functions as a total inversion of the lie-detector, which supposes that the body tells the truth, while we lie with our spoken words. With Bio Mapping, people’s interpretation and public discussion of their own data becomes the true and meaningful record of their experience. Talking about their body in this way, they are generating a new type of knowledge combining “objective” biometric data and geographical position, with the “subjective story” as a new kind of psychogeography. (2009, p. 8)

Given such attempts to appropriate the polygraph’s emotion-detecting capability and render its data observable and narrativizable "as a new kind of psychogeography" (Nold, 2009, p. 8), Nold’s project likely seems at this point very similar to Reynolds’s Mapping URI project or Lefebvre’s critical spatial theory. In their own ways, each of these projects aims to recover a sense of place as both represented (at the level of ideology or dominant discourse) and lived at the level of felt bodily sensation. Where Bio Mapping diverges from these other accounts of lived space, however, is in the particular attitude and assumptions it brings to these representational moments and to acts of representation more generally. As Nold acknowledged in many of his published writings, Emotion Maps can’t, and indeed shouldn’t, speak for themselves; by virtue of their inherent ambiguity, they require participants’ active interpretations, their willingness to engage their own bio-data as well as their recollections of the events measured by the GPS and GSR sensors. As Nold put it, "I personally don’t see the map being ‘representative’ but more as a discussion tool to argue a point" ("Interview," n.d., para. 16). For Nold, in other words, Emotion Maps are not themselves representational but rather function rhetorically as a kind of hermeneutic spark, inviting participants to offer narrative accounts of their own emotional experiences and to detail in varying degrees what they saw, did, and felt in a given time and place. "From talking with people who tried out the device," Nold reflected,

I was struck by their detailed and personal interpretations of their bio-data. Often we would sit next to each other and look at their track together. While I would see just a fairly random spiky trail, they saw an intimate document of their journey, and recounted events which encompassed the full breadth of life: precarious traffic crossings, encounters with friends, meeting people they fancied, or the nervousness of walking past the house of an ex-partner. (2009, p. 5)

In the interview above, for example, Nold provided a participant the opportunity to view and interpret her Emotion Map following an excursion in a London neighborhood. After being presented with an apparent instance of high emotional arousal (in this case marked by a cluster of red dots), the participant here began to fashion a narrative in which the beauty of the local architecture and her encounter with a small private garden served to trigger the emotional response documented by the GSR sensors. "I think that bit of the red dots," she speculated, "I made a phone call to tell someone about how great it was. And so, I think, that's sort of measuring my excitement at sharing that moment." Whether this narrative is or isn’t accurate is of less importance than the fact that the narrative itself emerged—indeed, can only emerge—retroactively, in the presence of a map claiming to document an experience that might never have been felt, and thus made available to the participant as experience, in the first place. For this participant, in other words, knowledge and memory of events only occured belatedly, in the attempts she made to retroactively name, theorize, or bring under a concept events depicted on the Emotion Map. "I’ve known this" about these familiar London streets, she offered, "but I haven’t had a chance to explore this." The language of epistemology not withstanding, her use of "knowing" here indicated that at some tacit level she has always "known" the effects these spaces have on her, even if that knowledge was never fully formed or made available to her before her encounter with this Emotion Map. Like many Emotion Map narratives, there’s an underlying uncertainty at play in this account, a sense that in the gap between the event of embodied spatial practice and the moment of its attempted interpretation something of that initial event is lost, perhaps irrevocably, as the unregistered impingements of her sensations are drawn imperfectly into relation with language’s revelatory powers to name them as such. To know one’s embodied being-in-the-world, the participant thus suggests, is only to know it belatedly, as what will have been.

Of course, this sense of a tacit knowing that precedes the work of narrative or memory did not prevent the participant from attempting to further define and theorize these documented sensations: "I find it fascinating on a personal level, that you do vary in your reactions. That your reactions are bodily as well as, I mean, I’m always thinking about cognitive reactions, but that your body responds to your cognitions." Such efforts to explain the meaning of an Emotion Map, including what it indicates about a past that may never have been experienced in the first place, are commonplace in the interpretative situations Nold staged with his participants. And yet, even as the presence of the Emotion Map encouraged participants to imagine their pre-theoretical and pre-reflective sensations as objects of knowledge waiting to be made present and commensurate with the language of knowledge and experience, Nold’s project suggests at the same time that regardless of what this injunction assumes I should also understand that the events which sparked these sensations will, by virtue of their embodied and temporal otherness, always remain to a certain degree irrecuperable, and thus irreducible to my attempts to recover them as such through speech or writing. So while Bio Mapping hoped to draw participants’ attentions to the constitutive force embodiment and spatiality hold in shaping experiences of everyday life, it aimed as well to dramatize the limitations inherent in any effort to fully discern with great confidence what constitutes, or should constitute, one’s being-in-the-world. As Nold described it, Bio Mapping participants

are carrying out a type of co-storytelling with the technology, that allows them to creatively disclose, or omit, as much as they like of what happened during their walks … This vision of Bio Mapping as a performative tool which mediates relationships is [thus] very different to [sic] the fantasy of Emotion Mapping that many people approached me about: such as marketeers’ intentions to metaphorically "slice people’s heads open to see their innermost feelings and desires." (2009, p. 6)

Far from slicing people’s heads open and unveiling the innermost depths of their feelings or desires, Bio Mapping asks instead that we imagine pre-reflective sensation as a kind of immemorial excess that can never be fully represented but which may be made available in language as a surplus or trace that at once withdraws from and continuously haunts our spoken and written accounts of past events. What participants got in their accounts of past embodied sensation, therefore (and what students get in their attempts to reflect on such sensations in writing, I would add), wasn't so much a description or representation of the feeling or stimulus itself—what led them to have the experience they now believe they have had—but an enactment of memory’s repeated failure to render the absent present in language. By inviting participants to confront this irreparable impasse between memory and forgetting, Nold’s Bio Mapping project holds a distinct and important rhetorical mission: attuning participants to their embodied being-in-the-world and to the ways unseen dramas of public intensity routinely play out on and beneath the surface of the skin, while at the same time inviting them to consider the limits of their ever gaining complete control over these dramas, whether through language, surveillance technology, or any other revelatory means.