Unseen Hand Research Articles

Necessity is the Mother of Invention: Reconstructing Missing Sensory Information in Multiple, Concurrent Reference Frames for Eye–Hand Coordination

When aligning the hand to grasp an object, the CNS combines multiple sensory inputs encoded in multiple reference frames. Previous studies suggest that when a direct comparison of target and hand is possible via a single sensory modality, the CNS avoids performing unnecessary coordinate transformations that add noise. But when target and hand do not share a common sensory modality (e.g., aligning the unseen hand to a visual target), at least one coordinate transformation is required. Similarly, body movements may occur between target acquisition and manual response, requiring that egocentric target information be updated or transformed to external reference frames to compensate. Here, we asked subjects to align the hand to an external target, where the target could be presented visually or kinesthetically and feedback about the hand was visual, kinesthetic, or both. We used a novel technique of imposing conflict between external visual and gravito-kinesthetic reference frames when subjects tilted the head during an instructed memory delay. By comparing experimental results to analytical models based on principles of maximum likelihood, we showed that multiple transformations above the strict minimum may be performed, but only if the task precludes a unimodal comparison of egocentric target and hand information. Thus, for cross-modal tasks, or when head movements are involved, the CNS creates and uses both kinesthetic and visual representations. We conclude that the necessity of producing at least one coordinate transformation activates multiple, concurrent internal representations, the functionality of which depends on the alignment of the head with respect to gravity.

Visual capture influences body-based indications of visual extent

Visual information regarding limb location can override proprioceptive information when there is conflict between the two-a phenomenon referred to as visual capture. In three experiments, we employed the "mirror illusion," in which the perceived location of one's hand is influenced by the visual information specified by the mirror reflection of the other hand, to test whether visual capture influences body-based indications of the extent of objects. Participants viewed their visible hand and its reflection in a mirror after the unseen hand was positioned at one of four locations on a tabletop. The unseen hand's location appeared to be the same distance from the mirror as the visible hand's location. After viewing the visible hand and its reflection while simultaneously performing simple finger movements with both hands, participants viewed a block and had to move their unseen hand to a position that would allow them to grasp the block between their two hands. Movements of the unseen hand relative to the visible hand were biased by the visual information, reflecting errors in moved hand position given visual-proprioceptive conflict. In Experiment 1, visual capture influenced the indications of object extent for objects within reach and aligned with the viewer's midline. Experiments 2 and 3 extended these findings to indications of extent for objects outside the viewer's reach (Experiment 2) and misaligned with the viewer's midline (Experiment 3). These results suggest that visual body information has a generalizable effect on actions used to indicate space perception that extends beyond egocentric spatial localization tasks.

Spatial coding of touch at the fingers: Insights from double simultaneous stimulation within and between hands

We studied the effect of tactile double simultaneous stimulation (DSS) within and between hands to examine spatial coding of touch at the fingers. Participants performed a go/no-go task to detect a tactile stimulus delivered to one target finger (e.g., right index), stimulated alone or with a concurrent non-target finger, either on the same hand (e.g., right middle finger) or on the other hand (e.g., left index finger = homologous; left middle finger = non-homologous). Across blocks we also changed the unseen hands posture (both hands palm down, or one hand rotated palm-up). When both hands were palm-down DSS interference effects emerged both within and between hands, but only when the non-homologous finger served as non-target. This suggests a clear segregation between the fingers of each hand, regardless of finger side. By contrast, when one hand was palm-up interference effects emerged only within hand, whereas between hands DSS interference was considerably reduced or absent. Thus, between hands interference was clearly affected by changes in hands posture. Taken together, these findings provide behavioral evidence in humans for multiple spatial coding of touch during tactile DSS at the fingers. In particular, they confirm the existence of representational stages of touch that distinguish between body-regions more than body-sides. Moreover, they show that the availability of tactile stimulation side becomes prominent when postural update is required.

Bimanual interaction of manual heightmatching to misperceived elevations of a target with different hand-to-body distances

The perceived elevation of a visual target at an observer's true eye level changes systematically with the pitch of the visual field: it appears to be raised in a pitched topbackward visual field and lowered in a pitched topforward visual field. However, the accuracy of manual pointing or heightmatching to a perceptually mislocalized visual target increases linearly with hand-to-body distance, approaching complete accuracy at full arm extension, with errors equal to the perceptual mislocalization for the hand close to the body. In the present experiments, we investigated bimanual interaction with the two hands held at different hand-to-body distances throughout a trial on manual tasks to a common visual target under pitch induction. Observers in darkness monocularly viewed a visual target at 70 cm distance in their median plane either 12° above, 12° below, or at eye level with a 50°-long line pitched either −30° (topbackward), or 20° (topforward) at 25° horizontal eccentricity. The manual heightmatching to the target was measured by a Polhemus 3-Space search coil with the unseen hand either in the midfrontal plane or at 20 cm or 40 cm in front of the midfrontal plane. The manual heightmatch to the visual target with either hand alone changed linearly with manual distance for each inducer pitch; manual heightsetting-vs-pitch functions were parallel for different target heights. With the two hands at different distances simultaneously, the height of the manual match to the target by the second hand to make a setting was influenced by the setting of the first hand. The average bimanual transfer of a setting from the baseline independence level approximated 44%, whether the first match was with the left or right hand. Hand dominance played an important role: 68% transfer was measured for the dominant to nondominant hand, 26% transfer was measured for the nondominant hand to the dominant hand.

Bimanual Interaction in Pointing to a Common Visual Target with Unseen Hands

Bimanual Interaction in Pointing to a Common Visual Target with Unseen Hands

Reach Adaptation and Proprioceptive Recalibration Following Exposure to Misaligned Sensory Input

Motor adaptation in response to a visuomotor distortion arises when the usual motor command no longer results in the predicted sensory output. In this study, we examined if exposure to a sensory discrepancy was sufficient on its own to produce changes in reaches and recalibrate the sense of felt hand position in the absence of any voluntary movements. Subjects pushed their hand out along a robot-generated fixed linear path (active exposure group) or were passively moved along the same path (passive exposure group). This fixed path was gradually rotated counterclockwise around the home position with respect to the path of the cursor. On all trials, subjects saw the cursor head directly to the remembered target position while their hand moved outwards. We found that after exposure to the visually distorted hand motion, subjects in both groups adapted their reaches such that they aimed ∼6° to the left of the intended target. The magnitude of reach adaptation was similar to the extent that subjects recalibrated their sense of felt hand position. Specifically the position at which subjects perceived their unseen hand to be aligned with a reference marker was the same as that to which they reached when allowed to move freely. Given the similarity in magnitude of these adaptive responses we propose that reach adaptation arose due to changes in subjects' sense of felt hand position. Moreover, results indicate that motor adaptation can arise following exposure to a sensory mismatch in the absence of movement related error signals.

Visuomotor adaptation and intermanual transfer under different viewing conditions

Does the brain use a separate internal model for cursor mechanics during visuomotor adaptation? We compared the amount of adaptation and transfer to the opposite arm when subjects reached the targets under different viewing conditions of the arm during reaching. If the brain forms separate models, we predict a difference in the amount of adaptation and transfer for each viewing condition. If the brain forms one model, we predict equivalent amounts of adaptation and transfer between the two hands for each viewing condition. Separate groups of subjects performed a reaching task with either a rotated view of cursor motion representing their unseen hand or a rotated view of their actual hand. The two groups were further divided so that the magnitude of the rotation was either 45 degrees or 75 degrees counter-clockwise. After adapting to the rotation with one hand, subjects reached the same targets under the same viewing condition but with the opposite hand. Similar amounts of adaptation and intermanual transfer were found across the different magnitudes of rotation and across patterns of hand-order. Our results suggest that the brain may not be learning a distinct model for cursor mechanics, or if it is, it must be equivalent or overlapping with the arm model.

Sensory integration in PMd: position-dependent dynamic reweighting of vision and proprioception

Event Abstract Back to Event Sensory integration in PMd: position-dependent dynamic reweighting of vision and proprioception Matthew Fellows1* and Phillip Sabes1 1 University of California San Francisco (UCSF), Department of Physiology and Keck Center , United States It has been observed behaviorally that human and non-human primates combine information from multiple sensory modalities. In many situations this combination has been found to be statistically near-optimal, meaning that the multi-modal (i.e., integrated) percept is formed by weighting each modality in proportion to its precision. However, sensory modalities are not represented homogeneously across cortex - for a given modality, both the strength of sensory representation and its functional role vary from area to area. How, then, do disparate local cortical representations manifest as globally optimal behavior? To begin addressing this question, we quantified – both behaviorally and in neurons – the integration of visual and proprioceptive information about hand location across a range of arm positions. We recorded simultaneous activity from large ensembles of dorsal premotor cortex (PMd) neurons in a monkey performing "out-to-center" reaching movements from multiple start locations to a central target, which he was required to fixate. We provided artificial visual feedback ("FB", a cursor) about the animal’s otherwise unseen hand location. This allowed us to impose a discrepancy ("FB shift") between the visual and proprioceptive feedback. We used FB shifts in different directions to measure how the animal weighted each modality when estimating hand location for reach planning. Optimality arguments predict that the integrated estimate of hand location should depend on the relative uncertainty of vision and proprioception. In general, these uncertainties are anisotropic and vary over space. That is, for hand localization, proprioceptive uncertainty changes with hand position, and visual uncertainty depends on hand position relative to gaze location. Therefore, due to the anisotropies, FB shifts in different directions should induce localization errors that differ in both magnitude and direction. In addition, due to the position-dependence, this pattern of shift-induced errors should change with start location. We quantified these error patterns both from the animal’s behavior and from population activity in PMd, and compared them. Behavioral analysis showed that the animal flexibly integrates vision and proprioception, with the weighting of each modality varying as a function of arm configuration: the observed error patterns showed systematic, position-dependent anisotropies. We observed flexible sensory reweighting in the PMd population activity as well, with error patterns that were similar to behavior in both orientation and position-dependence. However, the dependence on vision was greater for PMd than for behavior: for a given FB shift, the integrated hand location read-out from PMd is closer to the cursor than the location read-out from behavior. The spatial dependence we observed supports the idea that multi-modal integration, as measured with PMd activity and with behavior depends, at least in part, on the (anisotropic) variability of the sensory modalities. However, the greater dependence on vision in PMd suggests that sensory integration varies across the cortical reach circuit. For example, we expect that integration in primary motor cortex would look more like behavior than does PMd. This highlights the question of how diverse local cortical circuits are used in concert to drive overall behavior. Conference: Computational and Systems Neuroscience 2010, Salt Lake City, UT, United States, 25 Feb - 2 Mar, 2010. Presentation Type: Poster Presentation Topic: Poster session I Citation: Fellows M and Sabes P (2010). Sensory integration in PMd: position-dependent dynamic reweighting of vision and proprioception. Front. Neurosci. Conference Abstract: Computational and Systems Neuroscience 2010. doi: 10.3389/conf.fnins.2010.03.00094 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 20 Feb 2010; Published Online: 20 Feb 2010. * Correspondence: Matthew Fellows, University of California San Francisco (UCSF), Department of Physiology and Keck Center, Rijeka, United States, mrfellows@phy.ucsf.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Matthew Fellows Phillip Sabes Google Matthew Fellows Phillip Sabes Google Scholar Matthew Fellows Phillip Sabes PubMed Matthew Fellows Phillip Sabes Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

There is No Place Like Home: American Affirmation in Sam Shepard's Unseen Hand

The Journal of Popular CultureVolume 42, Issue 5 p. 875-889 There is No Place Like Home: American Affirmation in Sam Shepard's Unseen Hand DARL LARSEN, DARL LARSEN Brigham Young UniversitySearch for more papers by this author DARL LARSEN, DARL LARSEN Brigham Young UniversitySearch for more papers by this author First published: 01 October 2009 https://doi.org/10.1111/j.1540-5931.2009.00712.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume42, Issue5October 2009Pages 875-889 RelatedInformation

Contributions of vision–proprioception interactions to the estimation of time-varying hand and target locations

We investigated the relative importance of vision and proprioception in estimating target and hand locations in a dynamic environment. Subjects performed a position estimation task in which a target moved horizontally on a screen at a constant velocity and then disappeared. They were asked to estimate the position of the invisible target under two conditions: passively observing and manually tracking. The tracking trials included three visual conditions with a cursor representing the hand position: always visible, disappearing simultaneously with target disappearance, and always invisible. The target's invisible displacement was systematically underestimated during passive observation. In active conditions, tracking with the visible cursor significantly decreased the extent of underestimation. Tracking of the invisible target became much more accurate under this condition and was not affected by cursor disappearance. In a second experiment, subjects were asked to judge the position of their unseen hand instead of the target during tracking movements. Invisible hand displacements were also underestimated when compared with the actual displacement. Continuous or brief presentation of the cursor reduced the extent of underestimation. These results suggest that vision-proprioception interactions are critical for representing exact target-hand spatial relationships, and that such sensorimotor representation of hand kinematics serves a cognitive function in predicting target position. We propose a hypothesis that the central nervous system can utilize information derived from proprioception and/or efference copy for sensorimotor prediction of dynamic target and hand positions, but that effective use of this information for conscious estimation requires that it be presented in a form that corresponds to that used for the estimations.

Encounter with the Unconscious

Twelfth-century Hildegard of Bingen’s lush interior life foreshadowed twentieth-century Jungian insight into the rich contents of the unconscious in human personality. “Encounter with the Unconscious: Hildegard in Jung” provides an overview of the seven references in Jung's Collected Works to Hildegard of Bingen, who, in Jung's own words, was “an outstanding personality quite apart from her mysticism” (CW 13, ¶42). Murray Stein contends that Jung was guided in his writings “by an unseen hand, a largely unconscious spiritus rector [guiding spirit].” Eight centuries earlier Hildegard was motivated by the same impulse and guided by a similar spirit—the umbra viventis lucis—the Living Light within her soul. This article offers an interpretation of Jung's interest in a woman from another era upon whom he could rely while pioneering the rich, colorful, and symbolic spiritual terrain of the unconscious. Both medieval Benedictine Abbess Hildegard and modern depth psychologist Jung sought to heal a Christianity in crisis. Each experienced a visionary life that gripped them from within with images and ideas that have outlived them. Jung found in twelfth-century Hildegard a scientific theorist supportive of his findings on the life of the unconscious in human personality, as well as a mystic able to experience the visionary life while retaining psychic integrity— or, expressed within his conceptual framework, as a woman who achieved individuation, an evolved individuality.

The rubber hand illusion in action

In the well-known rubber hand illusion (RHI), watching a rubber hand being stroked while one's own unseen hand is synchronously stroked, induces a relocation of the sensed position of one's own hand towards the rubber hand [Botvinick, M., & Cohen, J. (1998). Rubber hands ‘feel’ touch that eyes see. Nature, 391(6669), 756]. As one has lost the veridical location of one's hand, one should not be able to correctly guide one's hand movements. An accurate representation of the location of body parts is indeed a necessary pre-requisite for any correct motor command [Graziano, M. S. A., & Botvinick, M. M. (1999). How the brain represents the body: Insights from neurophysiology and psychology. In D. Gopher, & A. Koriat (Eds.), Attention and performance XVII—Cognitive regulation of performance interaction of theory and application (pp. 136–157)]. However, it has not yet been investigated whether action is indeed affected by the proprioceptive drift towards the rubber hand, nor has the resistance of visual capture in the RHI to new proprioceptive information been assessed. In the present two kinematic experiments, we show for the first time that action resists the RHI and that the RHI resists action. In other words, we show a dissociation between illusion-insensitive ballistic motor responses and illusion-sensitive perceptual bodily judgments. Moreover, the stimulated hand was judged closer to the rubber hand for the perceptual responses, even after active movements. This challenges the view that any proprioceptive update through active movement of the stimulated hand erases the illusion. These results expand the knowledge about representations of the body in the healthy brain, and are in line with the currently most used dissociation between two types of body representations so far mainly based on neuropsychological patients [Paillard, J. (1991). Knowing where and knowing how to get there. In J. Paillard (Ed.), Brain and space (pp. 461–481); Paillard, J. (1999). Body schema and body image: A double dissociation in deafferented patients. In G. N. Gantchev, S. Mori, & J.Massion (Eds.), Motor control, today and tomorrow (pp. 197–214)].

Changing Reference Frames during the Encoding of Tactile Events

The mindless act of swatting a mosquito on the hand poses a remarkable challenge for the brain. Given that the primary somatosensory cortex maps skin location independently of arm posture [1, 2], the brain must realign tactile coordinates in order to locate the origin of the stimuli in extrapersonal space. Previous studies have highlighted the behavioral relevance of such an external mapping of touch, which results from combining somatosensory input with proprioceptive and visual cues about body posture [3-7]. However, despite the widely held assumption about the existence of this remapping process from somatotopic to external space and various findings indirectly suggesting its consequences [8-11], a demonstration of its changing time course and nature was lacking. We examined the temporal course of this multisensory interaction and its implications for tactile awareness in humans using a crossmodal cueing paradigm [12, 13]. What we show is that before tactile events are referred to external locations [12-15], a fleeting, unconscious image of the tactile sensation abiding to a somatotopic frame of reference rules performance. We propose that this early somatotopic "glimpse" arises from the initial feed-forward sweep of neural activity to the primary somatosensory cortex, whereas the later externally-based, conscious experience reflects the activity of a somatosensory network involving recurrent connections from association areas.

How does saccade adaptation affect visual perception?

Three signals are used to visually localize targets and stimulate saccades: (1) retinal location signals for intended saccade amplitude, (2) sensory-motor transform (SMT) of retinal signals to extra-ocular muscle innervation, and (3) estimates of eye position from extra-retinal signals. We investigated effects of adapting saccade amplitude to a double-step change in target location on perceived direction. In a flashed-pointing task, subjects pointed an unseen hand at a briefly displayed eccentric target without making a saccade. In a sustained-pointing task, subjects made a horizontal saccade to a double-step target. One second after the second step, they pointed an unseen hand at the final target position. After saccade-shortening adaptation, there was little change in hand-pointing azimuth toward the flashed target suggesting that most saccade adaptation was caused by changes in the SMT. After saccade-lengthening adaptation, there were small changes in hand-pointing azimuth to flashed targets, indicating that 1/3 of saccade adaptation was caused by changes in estimated retinal location signals and 2/3 by changes in the SMT. The sustained hand-pointing task indicated that estimates of eye position adapted inversely with changes of the SMT. Changes in perceived direction resulting from saccade adaptation are mainly influenced by extra-retinal factors with a small retinal component in the lengthening condition.

An Unseen Hand: The Role of Sociology Professor Ernst Borinski in Mississippi's Struggle for Racial Integration in the 1950s and 1960s

Based on archival and interview research, the current article examines the leadership roles of Tougaloo College's Sociology Professor Ernst Borinski, a German-Jewish Holocaust refugee, in Mississippi's racial integration struggles in the 1950s and 1960s. Embodying characteristics of both a bridge leader and a transformative intellectual, Professor Borinski worked behind the scenes and utilized the academy's resources and his status as an `outsider' to contribute to undermining Mississippi's racial status quo. As a bridge leader, Dr Borinski directly linked black and white groups together so that they could regularly meet, talk with one another, and develop critiques of racial segregation. As a transformative intellectual, Professor Borinski ensured that students understood their constitutional rights as American citizens and supported students and colleagues who were involved in the Mississippi civil rights movement. These two interlocking leadership roles encapsulate the contributions of Ernst Borinski to Mississippi's development from a `closed society' to a more racially integrated state.

Passion and Poison: Tales of Shape-Shifters, Ghosts, and Spirited Women (review)

Reviewed by: Passion and Poison: Tales of Shape-Shifters, Ghosts, and Spirited Women Karen Coats Del Negro, Janice M. Passion and Poison: Tales of Shape-Shifters, Ghosts, and Spirited Women; illus. by Vince Natale. Cavendish, 2007 [64p] ISBN 978-0-7614-5361-1$16.99 Reviewed from galleys R Gr. 5-8 Gather around a fire somewhere to share these creepy tales of women rubbing against the netherworld. These eight original tales and retellings all possess the uncanny feeling common to new takes on familiar traditional motifs, and they are enlivened by a voice so penetrating that it seems to be in the room rather than just on the page. From beastly men who get their just deserts, to bold women who brook no sass from inhabitants of this world or the next, to lonely children who find playmates among the green world, the tales explore themes of justice, courage, betrayal, vengeance, love, and just plain spookiness. The most moving is "Sea Child," wherein a mother grieving for her drowned son hears the wail of a child over several nights; she finally finds a young mother who has not allowed her own death by drowning to prevent her from caring for her infant until someone from the living world heeds the baby's call. Another mother protects her fortune from beyond the grave, ensuring that she find a female successor more worthy of its prize than her wastrel husband and son. Other tales find young girls taking care of business in various ways that usually result in the utterly just dispatch of their oppressors. While the focus of the stories is on strong women, there is no intrusive feminist message hampering the storytelling here—each of the tales finds its narrative arc naturally and without ideological coercion, with just a well-timed shiver here and there to let readers know that the unseen hands of justice in the universe are not idle. Copyright © 2008 The Board of Trustees of the University of Illinois

Ancient Privileges: 'Beowulf', Law, and the Making of Germanic Antiquity by Stefan Jurasinski (review)

252 Reviews 'take' on theworld (one inwhich the acknowledgment of the addressee's personal autonomy remains an important cultural premise). The wealth of evidence that Wierzbicka presents in every case firmlyanchors her research but in no way combines to render her text less than interesting arguments without compromising the clarity of her expositions, or rendering it less than highly readable. The style is lucid, clear, and logicallypresented, and whileWierzbicka can and does challenge conventional readings (her conclusions will no doubt be controversial in certain circles), thebook reveals, and sustains, a level of insightand sheer interest that isimmensely engaging. UNIVERSITY OF OXFORD LYNDA MUGGLESTONE AncientPrivileges:'Beowzuf', Law, and the Making ofGermanic Antiquity. By STEFANJURASINSKI. Morgantown: West Virginia University Press. 2006. x + I83 pp. $45. ISBN: 978-0-937058-98-5. AncientPrivileges discusses Germanic law and the editing of Beowu!f, two subjects with more in common thanmight be thought.Both were dominated by nineteenth-century Germans, who often saw them in thedistortingmirror of romantic nationalism.Jurasin ski setsout to remove thatglass, claiming that it misrepresents law and poetry alike, for all the 'aura of objectivity' (p. 3) thatphilologists claim for themselves. His book has an introduction,fourchapters, and a conclusion. The introductionoutlines theself-flatteries of patriotic romanticism and the manipulations of ideology.The unseen hand of imperialism and racial pride ledAnglo-Saxonists to exalt the law and poetry of theirancestors as a nobler and trueralternative to thehegemonies of Greek and Latin. Germanic lawswere seen as titledeeds of Teutonic freedom and egalitarianism, with Lord Acton informingCambridge students that theUS Declaration of Independence could be dimly perceived in the ancient 'forestsof Germany' (p. 7). Such delusions charmed not only historians. Stillworse, they interfered with textual interpretationand even emendation, which should be immune fromsuch a taint, like logic or algebra. The four chapters make the point in a series of case-studies. Chapter I discusses emendations byJakob Grimm and Friedrich Klaeber. Grimm, with Volksgeist inmind, thought that Wiglaf's denunciation of Beowulf's faithlesscompanions had legal forceas a formal expression of banishment. He thusemended hu 'how' to nu 'now' (1.2884) and (citingaModern German phrase) lufen'comfort' to leofen 'sustenance' (1.2886). Klaeber similarly interpreted goldhwete (1. 3074) on the basis of anathemas inAnglo-Saxon charters. YetJurasinski shows that the belief that these passages can be emended by reference to legal formulas has no substance. Chapter 2 deals with the rareword folcscare(1.73) uttered by Hrothgar. Jurasinski dispels themyth, dear to thehearts of commentators, that it means 'land common to the community'. Hrothgar cannot alienate certain possessions, not because theywere 'public', but because their statusmeant theyhad to remain within his family.Legal scholars grasped thepoint generations ago; but philologists have not noticed. Chapter 3 turns to animism and what the author calls the 'irrational, consuming fascinationwith vengeance' (p. 77) thatsupposedly governed Germanic folk.To the fore YES, 38.I & 2, 2008 253 here is the translation of woroldredenne(1. I142) in the Finn episode as 'universally acknowledged duty (of vengeance)'. By discussion of the laws,Jurasinski shows thatan enthusiasm by earlyGermans for 'sacred' blood feuds is illusory. Teutons likeBeowulf actually appear reasonable fellows,who could come to terms over disputes. It is nineteenth-century philologists who seem a wild, bloodthirsty lot, always ready (metaphorically speaking), inbetween bouts of treeworship, tohack off the arms and legsof anyone who fellfoulof them. The last chapter deals with the tragedyof Hrethel andfeohleas gefeoht (1.2441), taken as 'conflictbeyond compensation'. Jurasinski dismisses the claim thatGermanic law made no distinction between redress for murder and for manslaughter. IfHrethel took no action, it would not be because (p. 148) his sonHerebeald was killed by a kinsman, but because thedeath was accidental. This isa book of distinction. It is sober, lucid, precise, and illuminating.Even those with little interest inOld English may learn from itscomments on the psychology of scholars, for whom inertia is so potent, and the echoing of one's predecessors so very softan option. AncientPrivileges, therefore,isan outstanding achievement, greatly to the credit of itsauthor and of theUniversity ofWest Virginia. UNIVERSITY OF NAVARRE,PAMPLONA ANDREw BREEZE The Mabinogion. Trans.bySIONED DAViES. Oxford: Oxford University Press.2007.xxxviii + 293 pp- ?I2.99. ISBN:978-0-i9-283242-9. TheMabinogion is...

English: Meaning and Culture by Anna Wierzbicka (review)

Reviews English:Meaning and Culture.By ANNAWIERZBICKA. Oxford and New York: Oxford University Press. 2006. ix + 352 pp. QI7.99. ISBN: 978-O-I9-5I7475-5. Anna Wierzbicka's new book isa thoughtful,thought-provoking,and often illuminating work on thedistinctive cultural patterning ofmeaning and grammar within English. If the central ideas of a cultural scriptwithin language have previously been productively explored forlanguages such asJapanese, this isa territory which, asWierzbicka observes, has oftenbeen marginalized in modern linguisticanalysis of 'Anglo'English. Yet, as she firmlystates, 'English isnot a cultural tabula rasa'; touse English, as shemakes clear, is thereforealso toengage with a specificand distinctive cultural baggage thatexists at the heart of discourse. To examine the institution and deployment of what appear as quintessentially 'English' assumptions about fair play, reason (and reasonableness), precision, or the equally 'English' predilection for the use of hedges, forunderstatement, or for 'whim peratives' rather than direct commands, might, of course, seem to take us 'simply' into the realms of folklinguisticsand a form of popular social-cultural stereotyping on national lines. Wierzbicka rightlystresses thevalue of 'a coherent theoretical framework' and 'hard linguistic evidence'; in thiscontext, her previous work on natural semantic metalanguage (NSM) provides thecore principles of the formerand theevidential basis for the latter.By thesemeans, she argues, it ispossible to document not only a shared set of universal conceptual primes thatoperate within and between all languages, but also the cultural scripts that are specific to, and highly characteristic of, particular languages and theirspeakers. Such ideas of a formof 'cultural landscape' are intriguing,and are oftencompellingly argued. 'Fairness' and 'fairplay', for instance, can, asWierzbicka notes, operate so centrallywithin an Anglo world view that 'fornative speakers of English [...] (includ ingmany scholars), it is simplyunimaginable that "fairness" should not be a universal human concern'. Yet, in reality,such notions, and theircritical absence from thewell documented set of universal conceptual primes, strikinglyconfirm theways inwhich the constituent featuresof a native language can combine to shape culturally-specific ways of thinkingabout theworld. 'Fairness', in thissense,becomes a salient and distinc tive element of a cultural script of Anglo English which may baffle those whose language, and culture, is inscribed in different ways, and which may, in turn, lead to cultural translations or assumptions that are fundamentally misplaced (as in the examples that Wierzbicka gives of English biblical translation forchildren, or inher own eminently fair critique of notions of fairness as a biologically determined and hence universal property).The English 'whimperatives' ('could you/would you do X?' or 'she suggested that he do Y') likewise lack parallels in other languages, again providing a linguisticpatterning of thought,culture, and verbal behaviour that enacts a particular 252 Reviews 'take' on theworld (one inwhich the acknowledgment of the addressee's personal autonomy remains an important cultural premise). The wealth of evidence that Wierzbicka presents in every case firmlyanchors her research but in no way combines to render her text less than interesting arguments without compromising the clarity of her expositions, or rendering it less than highly readable. The style is lucid, clear, and logicallypresented, and whileWierzbicka can and does challenge conventional readings (her conclusions will no doubt be controversial in certain circles), thebook reveals, and sustains, a level of insightand sheer interest that isimmensely engaging. UNIVERSITY OF OXFORD LYNDA MUGGLESTONE AncientPrivileges:'Beowzuf', Law, and the Making ofGermanic Antiquity. By STEFANJURASINSKI. Morgantown: West Virginia University Press. 2006. x + I83 pp. $45. ISBN: 978-0-937058-98-5. AncientPrivileges discusses Germanic law and the editing of Beowu!f, two subjects with more in common thanmight be thought.Both were dominated by nineteenth-century Germans, who often saw them in thedistortingmirror of romantic nationalism.Jurasin ski setsout to remove thatglass, claiming that it misrepresents law and poetry alike, for all the 'aura of objectivity' (p. 3) thatphilologists claim for themselves. His book has an introduction,fourchapters, and a conclusion. The introductionoutlines theself-flatteries of patriotic romanticism and the manipulations of ideology.The unseen hand of imperialism and racial pride ledAnglo-Saxonists to exalt the law and poetry of theirancestors as a nobler and trueralternative to thehegemonies of Greek and Latin. Germanic lawswere seen as titledeeds of Teutonic freedom and egalitarianism, with Lord Acton informingCambridge students that theUS Declaration of Independence could...

Vergence modulation as a cue to movement in depth

It is known that the vergence state of the eyes can serve as a cue to distance. However, it has been claimed that changes in vergence induced by modulations of the binocular disparity of a random-dot display do not create a sensation of motion in depth. The present experiment tests the hypothesis that modulation of binocular disparity in a random-dot display does not create a sensation of motion in depth because, in such a display, looming of the image that normally accompanies motion in depth is absent. The image of a radial pattern remains self-similar when it moves in depth, so the absence of looming in such an image should not inhibit the effects of modulation of disparity. Subjects tracked with unseen hand the perceived motion in depth created by modulations of the disparity of a display of random spots, a single spot, and a radial pattern. As previously reported, the random-spot display produced almost no motion in depth. However, the single spot and the radial pattern produced motion in depth. It is concluded that modulations of vergence and/or of absolute disparity can create a sensation of motion in depth when the effects of looming are weakened or removed. However, strong sensations of motion in depth of isolated objects require the presence of looming.

Perception of hand motion direction uses a gravitational reference

We studied possible frames of reference for kinesthetic perception of imposed hand motion direction in the frontal plane in ten young adult subjects with no history of neuromuscular disease. In one experiment, subjects were instructed to set unseen hand motion imposed by a motorized linear slide device parallel to the trunk-fixed longitudinal axis, seven visually specified axes and vertical (gravitational axis) while in a standard erect head/trunk posture and with head/trunk orientation varied. The visually specified axes were presented on a head-mounted display that also blocked vision of the external environment. In a second experiment using the same device, subjects set unseen hand motion parallel to vertical and to subjective oblique directions of 45 degrees clockwise (cw) and counter clockwise (ccw) from vertical in erect and varied head/trunk postures. Errors for setting hand motion to vertical and to verbally specified oblique axes (45 degrees cw and ccw from vertical) were lower than to the trunk longitudinal axis and visually specified axes. There were clear oblique effects in setting hand motion to visually specified axes and to subjective oblique (45 degrees cw and ccw) axes. When head and trunk orientation were varied, variable errors were higher for all axes, but remained lowest for vertical and subjective oblique axes. Moreover, errors for setting hand motion to all axes depended on head/trunk orientation. Overall, these results show that kinesthetic perception of imposed hand motion uses a subjective gravitational frame of reference that varies somewhat with head/trunk orientation.