Bulletin of the Psychonomic Society 241 1977, Vol. 10 (4),241-282 CONDENSED SCHEDULE Thursday Morning Vision I (1-15) ... .. .. ..... ... , .. .. ... ... ... ...... ...... 8:30-12:35, Empire Room Information Processing 1(16-33) ... .. .... .. ...... .. ... .. .. 8:30-12:45, Palladian Room Attention and Vigilance (34-41) .. .. ; .... ... ... .... .. ..... .... .. 8:30-10:35, Club Room A Performance and Reaction Time (42-48) ... .. .. ..... .... .. ... ... 10:50-12:25, Club Room A Psychopharmacology (49-63) ...... .... ... ..... , ...... ..... .. .. 8:30-12:15, Forum Room Animal Conditioning (64-78) .. ; . ... ... .. .. .. .. ...... 8:30-12:30, Diplomat Room Avoidance Learning (79-88) .... ... ................... .. .. .. .... 8:30-11: 15 , Tudor Room Thursday Afternoon Perception I (89-107) . ...... .. ........ .. ... ... .. .. ... ..... 1:00-5:05, Empire Room Information Processing II (108-128) .. ... ... ..... ........ ... ..... 1:00-5:35, Palladian Room Social-Personality Processes (I 29-142b) .. .. ... ........ .. .. .. 1: 00-4:40, Club Room A Physiological (143-154) .. .. .... .. .. .. .. .. .. ... ... .. .. ... ... 1: 15-3:55, Forum Room Animal Motivation (155-163) . .. .. ........ ....... .. .. .. ... .. ... 1:00-3 :20, Tudor Room Brain Function I (164-170) .. .... ...... ... .. .. ... .. .. ... .. ... ... ... 3:55-5 :10, Tudor Room Memory and Recall I (l71-185b) .. .. .. .. .. .... ..... .......... 1:00 -5 :05, Diplomat Room Friday Morning Memory and Recall II (186-199) . .. .. ... ... .... .. .. .... .. ...... 8:30-12:30, Empire Room Information Processing III (200-215) . .. .. ... ... .. .... .. .. ... .. 8:30-12:40, Palladian Room Vision II (216-226) .. ... .. ... ... ......... .. ... ..... .. .. .. .. 8:~0-1l:40, Club Room A Perception II (227-245) .... ............ ..... .. .. .. .. '.. '~ .. .. : 8:30-12:30, Forum Room Animal Learning I (246-259) .. .......... ... ..... .. .. .... .. .. 8:30-12:40, Diplomat Room Problem-Solving and Concept Identification (260-270) ... .. ...... .. ... 8:30-11 :50, Tudor Room Friday Afternoon Memory and Recall III (271-286) . .......... .. .. .... ... .. .. .. .. .. 1:00-5:15;Empire Room Information Processing IV (287-301) . ... .. ..... ... .. ... ....... 1:00-5:05, Palladian Room Animal Learning II (302-316) . .. ... ..... .... .. .... ............ .. 1:00-5:05, Club Room A Brain Function II (317-33Ib) .. .. .. .. ... .. ..... .... .. .. .. .... .. .. 1:00-5:15, Forum Room Animal Behavior I (332-348) .......... .. .. ......... .. .. .... .. I :00-5:40, Diplomat Room Psycholinguistics (349-369) .. ... .. .... .. ... .. .. ...... .. .. ... ... 1:00-5 :35, Tudor Room Saturday Morning Memory and Recall IV (370-384) . .. ... ............. ... .. ...... .. 8:30-12:25, Empire Room Information Processing V (385-402) . .. ........... ....... ...... 8:30-12:45, Palladian Room Hearing (403-410) .. .... ... .. .. .. ...... ... ....... ..... ....... 8:30-10:40, Club Room A Psychophysics (411-417) ...... .. ... .. .. .. .......... .. ... ...... 11 :00-12:40, Club Room A Human Learning (418-429) ... .. .... .. .. .. .. ..... ... .. ..... .. .. .. 8:30-11 :40, Forum Room Animal Behavior II (430-440) .. ..... ; ..... .. ... .. .. ... .. ... 8:30-11 :20, Diplomat Room Reinforcement (441-454) . ........... .. ...... ... .. ... .. .. .. ... .. 8:30-12:20, Tudor Room BUSINESS MEETING HOSPITALITY G . Robert Grice, Chairman Palladian Room Ambassador Room Wednesday, Thursday, Friday Friday, 5:45 p.m. 6:00-11 :00 p.m. 242 (l-ll) Papers read at the 18th Annual Meeting of the Psychonomic Society The Shoreham Americana, Washington, D.C. November 10, 11, 12, 1977 VISION I BREAK-9:55 -/0:05 Philip Salapatek, University of Minnesota, Minneapolis Empire Room, Thursday morning, 8:30-12:35 10:05-10:25 (6) Monocular and Binocular Peripheral Acuity with Complex Stim­ 8:30-8:45 (1) uli at Photopic, Mesopic, and Scotopic Light Levels. JOHN R. Binocular Interactions in Human V~ion. SANDRA A. LEMA BLOOMFIELD & KURT GRAFFUNDER, Honeywell Systems & & RANDOLPH BLAKE, Northwestern University-Adaptation to Research Center-The peripheral acuity of six observers was mea­ a . grating pattern produces a temporary elevation in contrast sured in a display containing a 9 x 22 array of disk stimuli. The dif­ thresholds. We have measured the magnitude of this aftereffect ference in diameter of a just discriminable target from the nontar­ both monocularly and binocularly following adaptation of either get stimuli increased approximately linearly with retinal eccentric­ one or both eyes. Results reveal some new and interesting prop­ ity, at photopic, mesopic, and scotopic light levels for both binoc­ erties of mechanisms involved in binocular vision. ular and monocular viewing. ·8:45-9:00 (2) 10:25-10:35 (7) Metacontrast and Paracontrast of a Contourless Area. ARNOLD The Influence of Target-Nontarget Separation on Discrimin­ E. STOPER, California State University, Hayward, & GUY ability. JOHN R. BLOOMFIELD, Honeywell Systems & Research MANSFIELD, University of Oregon Medical School-The ap­ Center, & JERRY WALD, University of Minnesota and Honey­ parent brightness of an unbounded area of a large target figure well Systems & Research Center-Displays containing nontarget was suppressed by a mask adjacent to this area. This " area stimuli and a single target that differed in color mixture were used suppression" was shown to follow a U-shaped function of onset in two experiments. Target discriminability was measured using asynchrony between target and mask similar to that of "clas­ optical blur techniques. Discriminability was found to be a func­ sical" metacontrast, except that here the forward masking effect tion of the distance between stimuli, as well as of the physical char­ was as strong as the backward one. These results can be explained acteristics of the target and nontargets. in terms of a filling-in process which lags behind the peripheral 10:35-10:55 (8) brightness sensing process. An Economical Encoding for Size and Position Information. 9:00-9: 15 (3) BARBARA SAKITT, Stanford University, & HORACE B. Foveal vs. Peripheral Metacontrast: A Parametric Study. BARLOW, University of Cambridge.,-A model is proposed for BRUCE BRIDGEMAN & STUART LEFF, University of Califor­ the first stage of the cortical transformation of the visual image. nia, Santa Cruz-We have measured thestrength of metacontrast First, principles of engineering and signal detection theory are used masking with three stimulus sizes, each located foveally and at two to determine the minimum amount of information needed by the eccentric positions. Masking occurs in all locations; in the fovea, cortex. Second, we suggest a particular mathematical model by the smallest stimulus (target diameter 15 ' ) gives the strongest which the cortex might do this in the most economical way pos­ masking, while the reverse is true at the most peripheral position sible, subject to the restriction that the model conforms (approxi­ (9.2°). Results are interpreted in terms of physiological theories mately) to the psychophysical and electrophysiological evidence of masking. with regard to CSFs, size, position, and orientation selectivity. 9:15-9:35 (4) 10:55-11:10 (9) The Effect of Refractive Error on Movement Detection. Directional Selectivity: Tuning Functions and Discrimination ROBERT POST & H. W . LEIBOWITZ, Pennsylvania State Uni­ Performance. KARLENE BALL & ROBERT SEKULER, North­ versity-The influence of refractive error on movement sensitivity western University-Detection and reaction time experiments mea­ was determined for a range of stimulus durations in the fovea and sured the tuning of human direction- and velocity-specific mecha­ periphery. At short durations, threshold is determined by a con­ nisms. Mechanisms sensitive to upward movement generated nar­ stant stimulus displacement. At longer durations, a constant veloc­ rower tuning curves than those sensitive to oblique directions. ity is required. The correction of peripheral refractive error Tuning differences were paralleled by variation in ability to dis­ increases movement sensitivity in the displacement (short dura­ criminate changes in direction of movement. tion) component, but does not influence sensitivity in the velocity 11:10-11:25 (10) (long duration) component of the motion threshold. Paracontrast and Disinhibition. HALSEY H . MATTESON & 9:35-9:55 (5) THOMAS C. PRAGER, Tulane University-Stimuli were two Is Dynamic Spatial Orientation Independent of Luminance and stripes flanking a central rectangle. With the rectangle test, there Refractive Error? H. W. LEIBOWITZ, Pennsylvania State Uni­ was no disinhibition or paracontrast. With the stripes as test, in­ versity, & J. DlCHGANS, University of Freiburg, West Germany­ creased stripe brightness (disinhibition) occurred at test-mask Although luminance and refractive error are critical variables for asynchronies at which stripes (test) maximally masked the rec­ many central visual functions, neither luminance (within 0.5 log tangle (mask), and there was some paracontrast. unit of absolute threshold) nor refractive error (20 diopters) alone, 11:25-11:40 (11) or in combination, has any effect on peripherally mediated dynam­ Interactions Between Sustained and Transient Channels in ic orientation as measured by circularvection. The results are inter­ Humans. BRUNO G. BREITMEYER, University of Freiburg, preted within the context of multiple modes of information proces­ West Germany-Employing the metacontrast paradigm, it was sing, which argues for a dissociation