A worm-eating snail thats too big to fully fit into its shell. Alex Holcombe 2023-02-07 | The blue fringe of these hermaphrodites is thought to deter predators who may know that some sea slugs secrete acid.A rasp-like tongue helps this Hydatina physis to lap up worms.Seen in a rock pool in Royal National Park near Sydney, Australia.
Violet sea snail (janthina janthina) out of its shell, with goose barnacles Alex Holcombe 2025-02-21 | This animal has a bubble raft of his own mucus so that it can float on top of the ocean and eat top-dwelling jellyfish like bluebottles. The oscillating "breathing" cones are goose barnacles that are feeding on plankton.Sydney (Boat Harbour Marine Reserve), Australia
white-speckled seahare (Aplysia) Alex Holcombe 2024-10-07 | About 6 inches long, I found this one at Malabar Beach, Sydney. A different Aplysia species is popular among neuroscientists, as studies of their gill withdrawal when they are touched, used in many studies of the cellular and molecular basis of learning, led to the 2000 Nobel Prize in Physiology or Medicine to Eric Kandel.
A harmless Port Jackson shark in Sydney, Australia Alex Holcombe 2024-08-10 | Swims straight toward the beach, slowly enough that I was able to follow it for about 6 minutes.
Two young gorillas enjoy each other...until a toddler clit-blocks! Alex Holcombe 2024-07-07 | One young female gorilla mounts and humps another. Until the group's toddler, someone else's child, breaks up the fun.
Kraken? The giant cuttlefish Alex Holcombe 2024-04-30 | snorkeling with the world's largest cuttlefish species (Sepia Apama). Incredibly, this is just steps from a heavily-populated suburb of Sydney, Australia ( Fairy Bower, Manly).
Blue Groper fish and a school of yellowtail scad Alex Holcombe 2024-04-22 | Gordons Bay, Sydney, Australia
Lips moving so quickly, you cant see whats happening. Alex Holcombe 2023-08-14 | When you blow air hard through closed lips, at normal speed it's impossible to see exactly what the lips are doing. Your brain's visual system is too slow!In ultra slow-motion playback, all is revealed. The vision scientist Patrick Cavanagh (my PhD advisor) taught me this.00:00 Normal speed00:08 Ultra slo-moAt normal speed, you can see that the lips are moving, but not the relationship between them. For an explanation of the principles, see Holcombe, A. O. (2009). Seeing slow and seeing fast: Two limits on perception. Trends in Cognitive Sciences, 13(5), 216–221.Technical notes:-The lip movement is known as a voiceless bilabial trill.-For the normal speed version, I think it looks even blurrier in real life, but I didn't know how to create the correct amount of motion blur. I created the movie on my phone specifying a 1/30th sec frame rate.
Spider becomes visible due to motion Alex Holcombe 2023-08-13 | The spider has great camouflage... but motion breaks it. The difference in motion signals between the moving thing and the background allows our brain's perceptual system to see the spider.
Spider camouflage Alex Holcombe 2023-08-13 | This spider is easy to see, until it stops moving - then it disappears! When it is moving, the motion cue helps our brain's visual processing system distinguish it from the branch it is crawling on.
Measure your minds limit for tracking one target Alex Holcombe 2023-08-07 | Use your mind to keep track of the initially-white segment, but all the while keep your eyes fixed on the central dot. Note the speed at which you lose the target.Our experiments on this show that the limit is not really a speed limit, but rather is caused by temporal crowding. For an explanation, see trackinglimits.whatanimalssee.com/speedAndTime.html#temporal-limits-on-tracking oren.wikipedia.org/wiki/Multiple_object_tracking#Spatiotemporal_limitsor the original paper: jov.arvojournals.org/article.aspx?articleid=2193883
Room moves and baby falls Alex Holcombe 2023-08-03 | Visual information is used to control balance. When the room (walls and ceiling) moves towards the toddler, she falls backward. The room looming is visual input the toddler would normally get when falling forward, so she leans back to compensate.
This blue-fringed snail species (Hydatina physis) is far too large to fit into its shell! Alex Holcombe 2023-07-31 | ...
A Maori #octopus in Australia (from a longer vid on my channel) Alex Holcombe 2023-07-31 | In Victoria, Australia
Campus possum Alex Holcombe 2023-07-26 | Ibises aren't the only locals interested in bins.Not to be confused with N. American opossums, this brush-tailed possum is at the University of Sydney in Australia.
tenzing and contributorship Alex Holcombe 2023-06-16 | About tenzing, our open source tool at www.tenzing.club to help researchers provide contributorship information.0:00 why researchers should indicate who did what2:09 Alex's story4:34 journals are moving toward contributorship5:28 CRediT, the contributor roles taxonomy7:16 two unfortunate aspects of using credit 8:20 how tenzing can help9:52 demonstration of how to use tenzingVideo made at the request of Cancer Research UK
A very active Maori octopus (Macroctopus maorum) Alex Holcombe 2023-03-06 | Alongside Moyne river inlet in Port Fairy Coastal Reserve, Victoria, Australia
New Zealand ferry and water color Alex Holcombe 2022-12-17 | On the ferry to North Island, passing the ferry going south in Queen Charlotte Sound. Notice the water color coming through at the end
echidna winks and runs Alex Holcombe 2022-09-05 | Slowed down at the beginning, so you can see he winked at me. But then he took off!Central Coast, NSW, Australia
Identify the two letters that are circled - fast rate Alex Holcombe 2021-08-25 | An example from an attentional blink experiment.Goodbourn, P. T., Martini, P., Barnett-Cowan, M., Harris, I. M., Livesey, E. J., & Holcombe, A. O. (2016). Reconsidering temporal selection in the attentional blink. Psychological Science, 27(8), 1146-1156.
Identify the 2 letters that are circled Alex Holcombe 2021-08-25 | Part of an attentional blink experiment.Goodbourn, P. T., Martini, P., Barnett-Cowan, M., Harris, I. M., Livesey, E. J., & Holcombe, A. O. (2016). Reconsidering temporal selection in the attentional blink. Psychological Science, 27(8), 1146-1156.
Alex Holcombe on Contributorship. AFC Lab Talk Series Alex Holcombe 2021-07-12 | Title: Redressing imbalances in the kind of research that gets done and who gets credit for it Abstract: If we want good work to get done, we should credit those who do it. In science, researchers are credited predominantly via authorship on publications. But many contributions to modern research are not recognized with authorship, due in part to the high bar imposed by the authorship criteria of many journals. “Contributorship” is a more inclusive framework for indicating who did what in the work described by a paper, and many scientific journals have recently implemented versions of it. I will consider the motivation for and specifics of this change, describe the tenzing tool we created to facilitate it, and how we might want to support and shape the shift toward contributorship.
Simulation of the retinal image Alex Holcombe 2021-07-02 | The image communicated to our brains by our retinas have many flaws, such as the blindspot, the absence of S (blue) cones in fovea, and fewer receptors in the periphery. We do not notice any of these things, in part because the brain "fills in" these flaws. This simulation shows what things might look like if we had access to the raw retinal image - however, the parameters are not physiologically accurate, it was created only to illustrate the issues.The simulation omits the effects of chromatic aberration, blood vessels, and irregular photoreceptor spacing.Credit: Laurent Itti & Christof Koch
Koalas usually look like lumps. Alex Holcombe 2021-06-16 | If you're lucky enough to see one in the wild, usually it'll be asleep or barely moving.This one, however, is foraging quite actively, high in a eucalyptus tree. Mambo Wetlands, Port Stephens, NSW.
VSS2021 Introduction to Open Science Alex Holcombe 2021-05-22 | Part of the "Conversations on Open Science" VSS symposium.2021.visionsciences.org/?p=567The talk-motivates open science practices by appealing to scientific values and for its ability to speed science-gives an overview of poor reproducibility and the replication crisis-provides evidence of poor uptake of open practices in vision science-describes efforts to remedy this and tailor preregistration for common vision science designs
Asteroids, the 1979 video game by Atari. Alex Holcombe 2021-02-18 | The classic 1979 video game by Atari.Public domain video created by Michael Libby twitter.com/_m_libby_/status/1362187765404811264
A seal spa (bottom center) where the seals are frolicking on Tasman Island. Alex Holcombe 2020-12-15 | You'll have to view it full screen to see the seals.
Success (top) and perceptual failure (bottom, at fast rate) to pair color and motion Alex Holcombe 2020-08-27 | The bottom display reveals a temporal limit on vision, specifically on binding color with motion.For more on this, see trackinglimits.whatanimalssee.com/speedAndTime.html#temporal-limits-on-visual-cognitiondual3.75Hz1.25HzRedLeftInstructnsMaxQuality
Post hoc ergo propter hoc. Alex Holcombe 2020-03-22 | Trying to learn how to teach online. A video lecture for the University of Sydney's ATHK1001 - Analytical Thinking.
red-bellied black snake (venomous) at Warriewood Wetland Alex Holcombe 2017-09-18 | Red-bellied black snake. Apologies for the shaky camera work, but he was coming right at me.
barber pole, but no illusion Alex Holcombe 2016-01-24 | In this case, the direction perceived seems to always correspond to the true direction, as revealed by the corners when they are unoccluded. So no illusion. In the illusion, the pattern moves diagonally but you perceive it moving vertically due to the shape of the aperture.
Easy (top) and hard (bottom) perceptual pairing of color and motion Alex Holcombe 2012-06-03 | dual3 75Hz1 25HzRapidInstructnsMaxQuality
Feel your brain follow two moving objects. What is its maximum speed? Alex Holcombe 2012-05-22 | Use your mind to keep track of the initially-white segments. While doing that, keep your eyes fixed on the central dot. Then, note the speed at which you lose the target.Our studies show that the limiting factor is not actually speed, but rather is caused by temporal crowding. For an explanation of temporal crowding in this situation, see trackinglimits.whatanimalssee.com/speedAndTime.html#temporal-limits-on-tracking oren.wikipedia.org/wiki/Multiple_object_tracking#Spatiotemporal_limitsor the original paper: jov.arvojournals.org/article.aspx?articleid=2193883
Measure your minds speed limit for tracking two targets Alex Holcombe 2012-05-22 | Use your mind to keep track of the initially-white segment, but all the while keep your eyes fixed on the central dot. Note the speed at which you lose the target.Our experiments on this suggest that with so few distractors sharing the targets' trajectory, this may be a real speed limit on tracking, rather than a result of temporal crowding.For an explanation, see trackinglimits.whatanimalssee.com/speedAndTime.html#temporal-limits-on-tracking oren.wikipedia.org/wiki/Multiple_object_tracking#Spatiotemporal_limitsor the original paper: jov.arvojournals.org/article.aspx?articleid=2193883
Measure your minds speed limit for tracking one target Alex Holcombe 2012-05-22 | Use your mind to keep track of the initially-white segment, but all the while keep your eyes fixed on the central dot. Note the speed at which you lose the target.Our experiments on this show that the limit is not a real speed limit, but rather is caused by temporal crowding. For an explanation, see trackinglimits.whatanimalssee.com/speedAndTime.html#temporal-limits-on-tracking oren.wikipedia.org/wiki/Multiple_object_tracking#Spatiotemporal_limitsor the original paper: jov.arvojournals.org/article.aspx?articleid=2193883
Scientist meets Publisher Alex Holcombe 2011-09-22 | "Your manuscript has been accepted by the journal I own. Just sign here."Introduction to the issues: https://theconversation.edu.au/spread-the-word-scientists-are-tearing-down-publishers-walls-5098I give away all rights to this video to the extent possible by law and the Xtranormal terms of use.
ascent through DKL color space Alex Holcombe 2011-07-11 | From dark to bright, planes of Derrington Krauskopf Lennie color space, showing possible colors, calibrated for Diamond Pro 2070SB CRT screen. Colors won't be accurate on other screens. Letters R, G, B show the color of the corresponding phosphor alone, where it can achieve that luminance. Color of letter is phosphor's color. Coordinates are drawn in color of phosphor at maximum luminance. At higher luminances (late in movie), some parts of gamut cut off because lower luminances more interesting- because impossible to get much saturation at high luminances. Patches originally uniform, but may be degraded by youtube or your system. Created by Alex O. Holcombe with Psychopy code library (psychopy.org). Related blog post: http://wp.me/ph4jF-fk
Ascent through DKL color space Alex Holcombe 2011-07-11 | From dark to bright, in Derrington Krauskopf Lennie color space, shows possible colors, calibrated for Diamond Pro 2070SB CRT screen. Colors won't be accurate on other screens. Created by Alex O. Holcombe with Psychopy code library (psychopy.org)
Judge which colors are aligned. Slow rotation rate. Alex Holcombe 2011-06-16 | A test we used to determine the maximum rotation speed for which people could see which colors in the inner and outer rings were aligned. At this slow speed, the task is easy. However if we make the speed faster than we can show on Youtube, about 1.5 revolutions per second, people can no longer see which are aligned, even though they can still identify the colors.From Holcombe, A.O., Linares, D.L., & Vaziri-Pashkam, M. (2011). Perceiving Spatial Relations via Attentional Tracking and Shifting. Current Biology, doi:10.1016/j.cub.2011.05.031
Perceptual speed limit on judging relative tilt Alex Holcombe 2011-06-16 | Each set of stripes alternates between leftward-tilted and rightward-tilted. The orientation of those in the left pair always differs, and the orientation of those in the right pair is always the same. This should be easy to perceive at the rate of the top display, but in the middle display if the stripes alternate as fast as intended, whether the orientations are the same or different should be difficult to perceive as the speed limit for this judgment has been exceeded.The bottom display illustrates the percept when the alternation is speeded until it exceeds even the limit for flicker perception. This bottom display was created by averaging the two frames together, as the visual system does at high alternation rates.from: Seeing slow and seeing fast: Two limits on perception. Holcombe, A.O. Trends in Cognitive Science, 13(5):216-21.
baby falls when room moves Alex Holcombe 2009-08-19 | Demonstrates that visual information is used to control balance. When the room (walls and ceiling) moves towards the toddler, she falls backward. The reason is that's visual input the toddler would normally get when falling forward, so she leans back to compensate. I think the video was made in 1974 of David Lee's laboratory of the UK, who pioneered studies of optic flow on balance.
Brown Owl remarkable head stability Alex Holcombe 2009-08-19 | Owls can exhibit a remarkable head stability during angular movement of the body about any axis passing through the skull. K.E. Money 1962. See THE VESTIBULAR SYSTEM OF THE OWL Author(s): Money, K.E.; Correia, M.J. Abstract: Owls have a curious variability in the postrotatory head nystagmus following abrupt angular deceleration. Owls can exhibit a remarkable head stability during angular movement of the body about any axis passing through the skull. The vestibular apparatus in the owl is bigger than in man, and a prominent crista neglecta is present. The tectorial membrane, the cupula, and the otolithic membranes of the utricle, saccule and lagena are all "attached" to surfaces in addition to the surfaces bearing hair cells; these attachments are very substantial in the utricular otolithic membrane and in the cupula.
