Impact of Coordinate Transformation Uncertainty on Human Sensorimotor Control

Erik J. Schlicht, Paul R. Schrater · Journal of Neurophysiology · 2007 · neuroscience · 10.1152/jn.00160.2007 · record schlicht2007-coordinate-uncertainty
tag layer · index · concepts · authors · עברית

Where this record's text came from. faceted 2026-08 by reading the locally held text (pdftext); every evidence string verified as an exact substring of that text before merging. method is coded 'behavioural-experiment' because the primary evidence is human psychophysics (4 subjects in the visual condition, 5 in the target-occluded condition, hundreds of trials each); the facet vocabulary has no combined behaviour-plus-modelling value, so the Bayesian inference model — which supplies the quantitative predictions and reanalyses Lewald and Ehrenstein's (2000) published pointing data — is not visible in the method facet. Claim type is 'mechanism' rather than 'existence' because the paper's claim is causal in shape: grip aperture changes with gaze eccentricity because eye-position sensing errors propagate through the eye-to-head coordinate transformation. Sample size is very small (4 and 5 subjects) but the paper does not flag this as a limitation, so it is not recorded in the limitations array. 2026-08-15 and 2026-08-16 schema-0.3 passes: every quote verified as an exact substring of the staged text and anchored at merge time; concept terms verified present; every edge endpoint an existing node.

The quality of the text these quotes were cut from. symbol-font-not-extractable: mathematical notation is lost to '(cid:NN)' markers - 763 of them, 7.8% of an internal file by character, but only 7.2% sit isolated in running prose (the rest cluster inside formulae). the approximation and inequality operators render as markers. 11 distinct codes with the top two accounting for 44% - ONE SYMBOL FONT WITH NO ToUnicode MAP, not a general extraction failure; a broken text font needs hundreds of codes. THE ARGUMENT OF THE PAPER IS READABLE AND TAGGABLE; THE EQUATIONS ARE NOT. 32 live quotes, 1 carrying a marker. THE SECOND COPY IS NOT A REPAIR: the web page we fetched shows zero '(cid:NN)' and 515 '/H#####' operator codes instead - the same glyphs in a different notation, which is why a cid-only check calls it clean.

Some quotes on this page contain (cid:NN). The PDF this text was extracted from encodes 7 characters in a way that names no letter, so the extractor could not say what they were. The quotes keep them because a quote is reproduced exactly or it proves nothing — the marks are the source’s, not the tagging’s.

Some words in these quotes contain the wrong character. The PDF this text was extracted from substituted 23 characters inside a word — a currency sign or a stray accent where a letter pair belongs, as in signi¢cantly for significantly, or a single ligature glyph, as in conﬁdence. They are valid characters in the wrong place, so they survive every encoding check. The quotes keep them for the same reason as above, and a search of this page will not find the affected words.

How to read this page. The article itself is not reproduced here — this paper is not cleared for redistribution, so what follows is the tag layer alone. The evidence sentences are withheld with the article. The table at the foot lists every tag the record carries; each row names the facet it belongs to, and the whose words column says whether the tag records the paper's own wording or the tagger's sentence about the paper. Every tag links to each other paper in the corpus carrying it. The machine-readable edition of the same thing is the TEI file beside this one, where the tags live in standOff, and the article is at its publisher via the link below. When we have changed our mind. Some entries in the table begin with a word in capitals and the reason for it. EVIDENCE CORRECTED — the finding still stands, but we had quoted the wrong sentence from the paper, and the quotation has been replaced with the right one. RETRACTED — the entry itself was wrong; it stays on the page, marked, with the reason, rather than being deleted. WITHDRAWN AND REPLACED — the entry was wrong, and a corrected version of it appears in the entries below. Each mark carries its own reason, in brackets, because the reasons differ from one entry to the next. An entry we have WITHDRAWN is removed from this page and kept in the record, with its reason. A line reading Audit and a date is a later re-reading of the entry against its whole sentence: DOUBTFUL means it was kept, and the reason says what is loose about it. Quotation marks inside the tagger's sentence. Where a tag is the tagger's own sentence, a phrase in quotation marks inside it is borrowed from the paper — the tagger's wording around it is not. The paper's own sentence is the evidence quote for that row; on this page it is withheld with the article, and the article is at its publisher. Nothing inside quotation marks anywhere on this page is ours: if it is quoted, it is the paper's. Whose words a concept carries. A concept entry records a term the paper itself uses, so the term, the sense given for it, and its evidence are the paper's own words, quoted where the paper fixes them. This is the opposite of a sense entry in the tag table, which is the tagger's sentence about how the paper uses a term. Where a concept entry could not be grounded in the paper's words, the entry says so on its own row.

Tags on this paper

Every tag the record carries, each linking to every other paper in the corpus that carries it. A tag appears here whether or not its words occur in the article — the spans below are only the ones a sentence in this paper licenses. Of the 7 concept tags on this paper, 3 are grounded in a quoted sentence.

coordinate transformation uncertainty sensorimotor control Bayesian inference eye-centered coordinates remapping reference frame fixation marks THE UNCERTAINTY IS MANIPULATED WITHOUT MOVING THE TARGET: the object stays in one place and the participant's EYE POSITION is varied instead, which changes the transformation between eye and head and so adds uncertainty to the remapped location while leaving the object alone THE LEVER IS A KNOWN PROPERTY OF THE SYSTEM RATHER THAN AN INTERVENTION: the authors exploit the fact that error in encoding eye position already varies with saccade magnitude and with eccentricity from forward view, so simply choosing where to look sets the uncertainty THE PREDICTION IS BUILT AS A CONDITIONAL WITH BOTH ANTECEDENTS NAMED: if the brain stores targets in eye-centred coordinates AND compensates for the effects of the uncertainty, then the grip aperture must vary with eye position EVEN WHEN THE TARGET CANNOT BE SEEN the target is deliberately NEVER MOVED across the workspace, and the reason is stated: so that any change in reaching behaviour must come from eye position and viewing eccentricity rather than from the kinematic demands of reaching somewhere else and its position was CHOSEN to maximise the very quantity under study - placed so that the widest possible range of eye positions away from the target was available, giving the greatest range of uncertainty ONE FIXATION POINT IS DROPPED PURELY TO KEEP THE TWO CONDITIONS COMPARABLE: the zero-degree fixation is excluded because the occluder would block both the target and that fixation letter, so the visual and occluded groups see the same set of fixations TWO DESIGNS ARE RUN WITH THE SAME NUMBER OF REPETITIONS PER FIXATION, and the trade-off between them is stated rather than left implicit: the full range captures the functional form of the response profile, the partial range buys statistical power in less time visual information is removed at DIFFERENT MOMENTS DURING the reach using liquid crystal shutter glasses, while separate occluders remove information about the hand and the target the read-out is justified by prior work before it is used: maximum grip aperture is known to scale with object size and to INCREASE when visual information is degraded the experimental logic is stated as an if-then over that read-out: if grip aperture changes with eye position when the target is OCCLUDED, that is taken to suggest the brain uses knowledge of the transformation uncertainty when planning a reach from a stored location grasping reference frames coordinate transformation uncertainty (CTU) eye position maximum grip aperture Bayesian Bayesian model behavioural-experiment

Legend

relation to other work	`claim_relations`	how this paper stands to another: agrees, contradicts, extends, qualifies
claim type	`claim_type`	the shape of the claim: existence, mechanism, method, critique, prediction, null
concept edge	`concept_edges`	an asserted relation between two concepts, with the sentence asserting it
concept	`concepts`	an idea the paper works with, quoted where the paper uses it
content tag	`content_tags`	a finding, definition, quantity, statistic or variable named in the paper
control	`controls`	an experiment run to eliminate a rival explanation
limitation	`limitations`	what the paper says its evidence cannot support
mechanism	`mechanisms`	how the reported effect is said to come about
method	`method`	how the paper produced its evidence
phenomenon	`phenomenon`	the effect or regularity under study
sense	`senses`	a distinct use of a term, quoted where the paper fixes it
transfer	`transfers`	a method or concept carried in from another field
unrecordable relation	`unhoused_relations`	a relation the paper asserts that this vocabulary cannot express, with the reason

The paper

The full text is not reproduced here. This article is not cleared for redistribution, so the page carries the tag layer only. Its evidence sentences are withheld; the grounding status remains with each tag, and the article itself is at https://doi.org/10.1152/jn.00160.2007. The reading view exists for the papers whose licence permits it.

Every tag on this page

claim_relations 3 · claim_type 1 · concept_edges 2 · concepts 3 · content_tags 6 · controls 2 · limitations 5 · mechanisms 10 · method 1 · phenomenon 1 · senses 1 · transfers 1 · unhoused_relations 1

Relations on this page carry a quotation for the claim. Where a relation was separately evidenced — and so tested against the vocabulary for its type — the row says so; none of 2 relations here carry that mark. The rest are the tagger’s reading of the sentence quoted beside them.

facet	tag	field	conf.	whose words
claim_type	mechanism Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_type`		the paper's words
phenomenon	coordinate transformation uncertainty in reach-to-grasp Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`phenomenon`		the paper's words
method	behavioural-experiment Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: behavioural-experiment	`method`		the paper's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE UNCERTAINTY IS MANIPULATED WITHOUT MOVING THE TARGET: the object stays in one place and the participant's EYE POSITION is varied instead, which changes the transformation between eye and head and so adds uncertainty to the remapped location while leaving the object alone	`mechanisms[0]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE LEVER IS A KNOWN PROPERTY OF THE SYSTEM RATHER THAN AN INTERVENTION: the authors exploit the fact that error in encoding eye position already varies with saccade magnitude and with eccentricity from forward view, so simply choosing where to look sets the uncertainty	`mechanisms[1]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: THE PREDICTION IS BUILT AS A CONDITIONAL WITH BOTH ANTECEDENTS NAMED: if the brain stores targets in eye-centred coordinates AND compensates for the effects of the uncertainty, then the grip aperture must vary with eye position EVEN WHEN THE TARGET CANNOT BE SEEN	`mechanisms[2]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: the target is deliberately NEVER MOVED across the workspace, and the reason is stated: so that any change in reaching behaviour must come from eye position and viewing eccentricity rather than from the kinematic demands of reaching somewhere else	`mechanisms[3]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: and its position was CHOSEN to maximise the very quantity under study - placed so that the widest possible range of eye positions away from the target was available, giving the greatest range of uncertainty	`mechanisms[4]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: ONE FIXATION POINT IS DROPPED PURELY TO KEEP THE TWO CONDITIONS COMPARABLE: the zero-degree fixation is excluded because the occluder would block both the target and that fixation letter, so the visual and occluded groups see the same set of fixations	`mechanisms[5]`	0.85	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: TWO DESIGNS ARE RUN WITH THE SAME NUMBER OF REPETITIONS PER FIXATION, and the trade-off between them is stated rather than left implicit: the full range captures the functional form of the response profile, the partial range buys statistical power in less time	`mechanisms[6]`	0.95	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: visual information is removed at DIFFERENT MOMENTS DURING the reach using liquid crystal shutter glasses, while separate occluders remove information about the hand and the target	`mechanisms[7]`	0.85	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: the read-out is justified by prior work before it is used: maximum grip aperture is known to scale with object size and to INCREASE when visual information is degraded	`mechanisms[8]`	0.85	the tagger's words
mechanisms	mechanisms Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: the experimental logic is stated as an if-then over that read-out: if grip aperture changes with eye position when the target is OCCLUDED, that is taken to suggest the brain uses knowledge of the transformation uncertainty when planning a reach from a stored location	`mechanisms[9]`	0.85	the tagger's words
limitations	An attentional-load account of the occluded-condition effect cannot be excluded by the data, only argued against. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the target-uncertainty account of the occluded condition: IT MAY BE THAT HOLDING EYE POSITION AWAY FROM FORWARD VIEW CREATES AN ATTENTIONAL LOAD THAT AFFECTS GRASPING	`limitations[0]`		the tagger's words
limitations	The results are consistent with, but do not establish exclusive, eye-centred storage; multiple simultaneous reference frames remain possible. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: any exclusive claim for eye-centred storage: OUR RESULTS DO NOT PRECLUDE THE POSSIBILITY THAT TARGET INFORMATION IS STORED IN MULTIPLE COORDINATE FRAMES	`limitations[1]`		the tagger's words
limitations	The visual fixation marks used in the task may themselves have induced the eye-centred storage strategy the study infers. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the eye-centred conclusion, which the apparatus may have produced: ANOTHER POSSIBILITY IS THAT VISUAL FIXATION MARKS PROMOTED AN EYECENTERED STORAGE STRATEGY	`limitations[2]`		the tagger's words
limitations	The model assumes large memory uncertainty and the data could not adjudicate a limited-memory alternative. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. what this limits: the large-memory-uncertainty assumption: WE COULD NOT REJECT A LIMITED MEMORY MODEL ON THE BASIS OF CROSS-TRIAL ANALYSES - ANY INFLUENCES OF FIXATIONS FROM PREVIOUS TRIALS WERE TOO SMALL TO BE RELIABLY MEASURED	`limitations[3]`		the tagger's words
limitations	The paper's own alternative explanation is that the apparatus induced the strategy the study infers: the visual fixation marks may have 'promoted an eye-centered storage strategy', being usable to maintain a representation of the body's configuration with respect to the apparatus. It is raised as a possibility and not settled, so the inference from behaviour to storage frame is conditional on the fixation marks not having supplied the frame. Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`limitations[4]`	0.9	the tagger's words
transfers	a Bayesian model of location inference used to predict how grip aperture compensates for coordinate-transformation uncertainty Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`transfers[0]`	0.85	the tagger's words
controls	the whole experiment was re-run on a DIFFERENT GROUP with a visual occluder that showed the target but not the hand Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. eliminates: that maximum grip aperture reflects something other than uncertainty about object LOCATION - the occluder holds target visibility constant while removing hand vision · outcome (stated by the tagger, no quotation): held	`controls[0]`	0.95	the tagger's words
controls	a fully visual condition run alongside the uncertainty conditions Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. eliminates: that grip aperture fails to track uncertainty at all - the visual condition establishes that the measure responds when it should · outcome (stated by the tagger, no quotation): held	`controls[1]`	0.95	the tagger's words
concepts	remapping Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: remapping	`concepts[4]`	0.95	the paper's words
concepts	reference frame Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: reference frame	`concepts[5]`	0.95	the paper's words
concepts	fixation marks Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: fixation marks	`concepts[6]`	0.9	the paper's words
unhoused_relations	saccade magnitude → eye position Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. THE TWO CANNOT BE SEPARATED IN THIS STUDY - the DESIGN form of the negative relation / No edge type can express it: all eight assert that a relation HOLDS. A confounding statement bounds what the paper's own results can mean, and it lives where nothing downstream will find it. Two sources of the same uncertainty, inseparable because of where the subjects were asked to look. — about this quote: DAMAGED GLYPHS IN THIS QUOTE: (cid:1), (cid:5). These are raw PDF font glyph indices that leaked out in place of the characters they stand for - usually a mathematical operator. The quote is verbatim to the staged text and its anchor is sound; the STAGED TEXT is what is damaged. NOT repaired: the cid-to-character mapping is defined by the font embedded in that particular PDF, so guessing it would produce a clean and unverifiable quote. Repair needs the source PDF and is a re-staging job.	`unhoused_relations[0]`		the tagger's words
senses	reliability - AS A PROPERTY OF THE STORAGE FORMAT, NOT OF THE MEASUREMENT: the same target information is more or less reliable according to which coordinate frame holds it, because each remapping between frames degrades the estimate Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`senses[0]`	0.95	the tagger's words
claim_relations	builds-on → Sober and Sabes (2005) Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_relations[0]`		the tagger's words
claim_relations	extends → neural and pointing evidence for eye-centred target storage (Batista et al. 1999; Pouget et al. 2002; Henriques et al. 1998; Crawford et al. 2004; Lewald and Ehrenstein 2000; Mergner et al. 2001) Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_relations[1]`		the tagger's words
claim_relations	extends → Lewald and Ehrenstein (2000) pointing data Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`claim_relations[2]`		the tagger's words
concept_edges	remapping —causes→ coordinate transformation uncertainty Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. strength of the relation: 0.9 · note: EVERY CONVERSION BETWEEN REPRESENTATIONS COSTS ACCURACY, STATED FLATLY: '…by each transformation made…' And the system is said to respond by choosing its format accordingly - '…that minimize the impact…' (Sober and Sabes 2005). The format is not a neutral container: it is picked to minimise conversion loss. Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span defines coordinate transformation uncertainty; remapping is not named in it. also in: remapping · coordinate transformation uncertainty	`concept_edges[0]`	0.95	the tagger's words
concept_edges	reference frame —causes→ coordinate transformation uncertainty Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. strength of the relation: 0.9 · note: THE SAME TARGET IS MORE OR LESS RELIABLE DEPENDING ON WHICH FRAME IT IS STORED IN: '…depending on the reference frame used for storage…' The reliability is a property of the storage format rather than of the object measured, which is why the paper can infer the frame from behaviour at all. Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span says CTU creates reliability differences DEPENDING ON the reference frame; causes is loose. also in: reference frame · coordinate transformation uncertainty	`concept_edges[1]`	0.95	the tagger's words
content_tags	the amount of compensation is predicted by a Bayesian eye-centered model Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[1]`		the tagger's words
content_tags	sensory information in different reference frames must be remapped into a common frame before integration Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.	`content_tags.findings[2]`		the tagger's words
content_tags	eye position Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: eye position	`content_tags.variables[0]`		the tagger's words
content_tags	maximum grip aperture Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. about this quote: THE QUOTE STOPS WHERE THE EXTRACTED TEXT GOES OUT OF ORDER: after its last word the extraction gives 'visual' and then 'is occluded. Moreover, …', but the words between them ('information and for changes in CTU…') appear further on, so the sentence cannot be completed from this copy. also in: maximum grip aperture	`content_tags.variables[1]`		the tagger's words
content_tags	coordinate transformation uncertainty (CTU) Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: coordinate transformation uncertainty (CTU)	`content_tags.definitions[0]`		the tagger's words
content_tags	Bayesian Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above. also in: Bayesian	`content_tags.statistics[0]`		the tagger's words

Interpretive choices

Tags that could not be placed in the text:

none — every tag was located in the text

What was deliberately not tagged, and why, is recorded per paper by the tagger. Where a paper has no such record, this page says so rather than implying that nothing was declined.