Julian Hochberg

The effect of landmark features on mental rotation times

By varying what we take to be the saliency oflandmarks (which are cues to location and orientation that are unique and visible from a distance), the slopes and intercepts of the time/angle function in the “mental rotation” task were caused to vary accordingly.

On cognition in perception: Perceptual coupling and unconscious inference

DO our perceptions of the world entail cognitive processes (comput,ations, inferences), or are they direct responses to ;he informative patterns of stimulation that act on our sense organs? To Helmholtz, as to J. S. Mill, channels of direct sensory response, which analyze the: patterns of stimulation into raw sensory responses, do not contribute directly to experience. The expectation of what patterns of sensation any given sensorimotor exploration would bring (the ‘permanent possibilities of sensation’) was taken as the percept. As Cassirer pointed out ( 1944), Helmholtz was saying that from the transformations in the pattern of sensations that result from exploratory movements, we perceive the invariances that are produced by, and specify, constant objects in the world. At least. three components must be distinguished : Stage A : The patterns of stimulation normally provided by the regularities in the physical world. Stage & : The channels of specific nerve energies. These result in preconscious events. They define the psychologically relevant effects of stimulation, but are not themselves psychologically accessible, and are known only by the constraints that they impose on what we can perceive; e.g., two points of light that stimulate onrly one and the same channel will be indistinguishable, so that discrimination psychophysics is one way to define the channels. Stage C: The patterns of expectations that have been learned from experience with A, above, viu B. These comprise mental structures (Hochberg, 1981), that reflect both the structure of the world, and the characteristics imposed by the sensory analysis in B. This last point amounts to what I have called Helmholtz’l Jle (Hochbl=rg, 1974, 1978): that we perlceive that object or event which would, under normal seeing conditions, be most likely to produce the pattern of sensations that we receive. To fit a perceived object or event to the sensary data in this way amounts to an unconscious inference, in which the premises are tb.e constraints in both A and B.

Geometrical illusions in solid objects under ordinary viewing conditions

The Müller-Lyer and Ponzo illusions were obtained under free binocular viewing of three-dimensional objects, and the function relating magnitude of illusion to fin angle, characteristic of converging-line versions of the Müller-Lyer pattern, was closely paralleled by volumetric (three-cone), line-free objects (but not with an erect, planar “walk-through” construction and moving observers). Illusions cannot be dismissed as artifacts of static, impoverished viewing, therefore, but must be explained within any general theory of perception. Perspective explanations have difficulties with such three-dimensional manifestations, and seem completely inapplicable to our further finding that approximately the same amount of illusion occurred in objects and patterns with no oblique lines or edges. Confusion or averaging theories, not themselves tested here, remain unthreatened by these data.

Machines should not see as people do, but must know how people see

Human perceptions of real objects and events, and of pictures of them, differ from physical and from depicted reality in many critical ways: in the prevalence of robust illusions of space and motion; in a tolerance of spatial inconsistencies; in being not everywhere dense. Such anomalous phenomena, and the classical pictorial depth cues as well, have been held in recent perceptual theorizing to be artifacts of static, impoverished line drawings, and it is asserted (with essentially no support) that the information about the world that is potentially available to a moving viewer in fact results in direct veridical perception of objects and events; causes the anomalies to vanish; and renders the pictorial depth cues unnecessary, irrelevant, and powerless. The constraints needed to use such motion-based information are usually given as rigidity or invariance preferences. We show that the major classes of misperception described above, and the effects of static pictorial cues, occur in force with moving object or observer, readily overcoming rigidity and invariance constraints, if such exist in humans. Machine vision, if subject to these anomalies, would be unnecessarily (so far as we now know) faulty. Machines that provide pictorial information to humans, unfiltered by human editors, should be so programmed as to avoid or compensate for the strong anomalies described. Current perceptual knowledge and theory are evaluated in relation to these phenomena.

On the control of saccades in reading

The simulation experiment performed by Dr. Bouma (1974). in which text was moved past a stationary fixation point, does not permit him to draw the following two conclusions about normal reading in which the eye is free to move at will: (1) that ~~r~p~~~u~ ,~f,u~c~z guidance (peripherally detectable features, like word spaces) cannot mediate cognitive search guidance (knowledge of where information is to be found: cf. Hochberg, 1970; Hochberg and Brooks, 1970); (2) that individual saccades are largely independent of visual text recognition, and that only the average proceeding of the eye over the text need be controlled by proceeding text recognition. To the first point (and possibly to the second, as well), normal reading usually contains leftward regressions to re-examine specific words and rightward recovery from these to fresh text (cf. Geyer, 1966; cf. Buswell. 1937, Plates I-IV): clear detionstrations of peripherally-mediated cognitive search guidance, which Dr. Bouma’s simulation procedure prevented. To the second point. there is now direct evidence that if the text which the reader has not yet fixated (but which is within 4-6 letter spaces from the fovea) is changed while his eye is in mid-motion, the very next fixation will be of increased duration (McConkie and Rayner, 1973; Rayner, 1973).

The effect of spatial order on piecemeal shape recognition: A developmental study

Stationary shapes were displayed piecemeal by moving an aperture from one place to another around their contours. Shape recognition was poorer with an unpredictable order of display. This result is more consistent with hypothesis-testing than with either eye-movement or visual information models of shape recognition. Shape recognition was poorer for 9- and 11-year-old children than for adults.

The facilitation of picture discrimination after object discrimination learning in the neonatal monkey and probably vice versa

Two groups of 20-day-old rhesus monkeys were trained to discriminate a three-dimensional vs a two-dimensional object or a pictorial representation of the objects. Object discrimination was significantly faster than pictorial discrimination, and reversal transfer tests showed significant savings in both cases. However, Ss trained on the object-picture sequence completed all training before any Ss completed the initial picture problem. The performance of the picture-object group in transfer tests did not differ significantly from other groups of comparable age.

Necessary Considerations for a Theory of Form Perception: A Theoretical and Empirical Reply to Boselie and Leeuwenberg (1986)

Boselie and Leeuwenberg (1986) recently defended their version of the minimum principle, called structural information theory or SIT, against a varied set of criticisms. Two of the most notable of these criticisms are (i) that perceptual organization can proceed as a piecemeal, rather than as a global, process (as demonstrated by partially-biased Necker cubes and ‘impossible’ figures), and (ii) that perceptual organization is influenced by subjective variables as well as by stimulus variables (Peterson and Hochberg 1983). The second criticism was acknowledged by Boselie and Leeuwenberg but not addressed. The first criticism was addressed by the introduction of two new variables into SIT in order to argue that the perceived organization of partially-biased Necker cubes and impossible figures can be predicted by a global coding scheme, thereby supporting rather than refuting global minimum principles. It is argued here that the criticisms cannot be dismissed by this rebuttal, which is focused narrowly on single examples rather than on the general principles embodied by the demonstrations. The implications of piecemeal perception and subjective mediation are spelled out, and both old and new data showing that the applicability of global minimum principles must be reexamined, not merely defended, are discussed. Finally, the argument for a richer, more interacting, theory of form perception is presented.

Age differences in sequential form recognition

Children (ages 3.7 to 9.2 years) viewed patterns moved continuously behind a stationary aperture, identifying the shapes by referring to a confusion matrix. Age affected recognition of sequentially viewed (but not simultaneously viewed) shapes; recognition errors for the different shapes (square, cross, and “E”) were only marginally different.

Age differences in shape recognition through an aperture in a free-viewing situation*

Young children (ages 4 to 10) show large deficits in correct shape recognition when the shapes are shown piecemeal through an aperture (Girgus & Hochberg, 1970). This study investigates whether allowing an S to self-program the sequential input results in accurate recognition performance. The stimuli used were a square, a cross, and a block “E.” The absence of self-programming in the earlier experiment apparently cannot account fully for the age-related deficits found in that research inasmuch as the results of this experiment still show a significant age effect.