Structural Representation of Object Shape in the Brain
Bibliographic record
Abstract
Introduction In Chapter 1, Dickinson analyzes the complex history of theoretical and computational vision. With some exceptions, the trend in recent decades is away from explicit structural representation and toward direct mapping of image features to semantic categories based on machine learning. The best-known formulations of the older, structural paradigm are those of Marr (Marr and Nishihara 1978) and Biederman (1987), although the central idea that objects are represented as configurations of parts has a long history (Barlow 1972; Binford 1971; Dickinson, Pentland, and Rosenfeld 1992; Hoffman and Richards 1984; Hubel and Wiesel 1959, 1968; Milner 1974; Palmer 1975; Selfridge 1959; Sutherland 1968). A configural representation would be carried by ensembles of processing units or neurons, each encoding the shape and relative position of a constituent part. This coding format is appealing because it solves three major problems in object vision. The first problem is the enormous dimensionality (on the order of 10 6 ) of retinal activity patterns. A signal of this complexity is too unwieldy to communicate between brain regions (owing to wiring constraints) or store in memory (owing to limited information capacity of synaptic weight patterns). Compression of this signal into a list of part specifications on the order of 10 1 to 10 2 would make communication and storage more practical. The second problem is the extremely variable mapping between retinal images and object identity. The same object can produce an infinity of very different retinal images depending on its position, orientation, lighting, partial occlusion, and other factors.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.007 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".