Editing Motion perception (section)

==Motion integration==
Some have speculated that, having extracted the hypothesized motion signals (first- or second-order) from the retinal image, the visual system must integrate those individual ''local'' motion signals at various parts of the visual field into a 2-dimensional or ''global'' representation of moving objects and surfaces. (It is not clear how this 2D representation is then converted into the perceived 3D percept) Further processing is required to detect coherent motion or "global motion" present in a scene.<ref name="BurrSantoro2001">{{cite journal | vauthors = Burr DC, Santoro L | title = Temporal integration of optic flow, measured by contrast and coherence thresholds | journal = Vision Research | volume = 41 | issue = 15 | pages = 1891–9 | date = July 2001 | pmid = 11412882 | doi = 10.1016/S0042-6989(01)00072-4 | s2cid = 16751457 | doi-access =  }}</ref>

The ability of a subject to detect coherent motion is commonly tested using motion coherence discrimination tasks. For these tasks, dynamic random-dot patterns (also called ''random dot kinematograms'') are used that consist in 'signal' dots moving in one direction and 'noise' dots moving in random directions. The sensitivity to motion coherence is assessed by measuring the ratio of 'signal' to 'noise' dots required to determine the coherent motion direction. The required ratio is called the ''motion coherence threshold''.