The author extends thanks to members of the Whitman College Comparative Psychology Lab for their help in data collection, including Mark Arand, Michael Barker, Eva Davis, Kuba Jeffers, Brett Lambert, Tara Mah, Theo Pratt, Tvan Trinh, Lyla Wadia, and Patricia Xi.

The procedure described here is in accordance with the Office of Laboratory Animal Welfare and with US Public Health Service Policy on Humane Care and Use of Laboratory Animals, and was approved by Whitman College&#39;s Institutional Animal Care and Use Committee.
1. Reduce Pigeons&#39; Weights
NOTE: Pigeons&#39; weights are reduced to 80 - 85% of their free-feeding weight33 to ensure that the birds are healthy and adequately motivated to work ...

<ol>
	<li>Loftus, E. F., Pickrell, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+formation+of+false+memories.">The formation of false memories.</a> Psychiat. Ann. 25 (12), 720-725 (1995).</li><li>Kahneman, D., Tversky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prospect+theory:+An+analysis+of+decision+under+risk.">Prospect theory: An analysis of decision under risk.</a> Econometrica. 47, 263-291 (1979).</li><li>Granberg, D., Brown, T. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Monty+Hall+dilemma.">The Monty Hall dilemma.</a> Pers. Soc. Psychol. B. 21, 711-723 (1995).</li><li>Simons, D. J., Levin, D. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Failure+to+detect+changes+to+people+during+a+real-world+interaction.">Failure to detect changes to people during a real-world interaction.</a> Psychon. Bull. Rev. 5, 644-649 (1998).</li><li>Grimes, J., Akins, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+failure+to+detect+changes+in+scenes+across+saccades.">On the failure to detect changes in scenes across saccades.</a> Perception. , 89-110 (1996).</li><li>Simons, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+sight,+out+of+mind:+when+object+representations+fail.">In sight, out of mind: when object representations fail.</a> Psychol. Sci. 7, 301-305 (1996).</li><li>Levin, D. T., Simons, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Failure+to+detect+changes+to+attended+objects+in+motion+pictures.">Failure to detect changes to attended objects in motion pictures.</a> Psychon. Bull. Rev. 4, 501-506 (1997).</li><li>Divita, J., Obermayer, R., Nugent, W., Linville, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Verification+of+the+change+blindness+phenomenon+while+managing+critical+events+on+a+combat+information+display.">Verification of the change blindness phenomenon while managing critical events on a combat information display.</a> Hum. Factors. 46, 205-218 (2004).</li><li>Rensink, R. A., O'Regan, J. K., Clark, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=To+see+or+not+to+see:+The+need+for+attention+to+perceive+changes+in+scenes.">To see or not to see: The need for attention to perceive changes in scenes.</a> Psychol. Sci. 8 (5), 368-373 (1997).</li><li>Rensink, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+detection.">Change detection.</a> Ann. Rev. Psychol. 53, 245-277 (2002).</li><li>Williams, P., Simons, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detecting+changes+in+novel,+complex+three-dimensional+objects.">Detecting changes in novel, complex three-dimensional objects.</a> Visual Cogn. 7, 297-322 (2000).</li><li>Regan, J. K., Deubel, H., Clark, J. J., Rensink, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Picture+changes+during+blinks:+looking+without+seeing+and+seeing+without+looking.">Picture changes during blinks: looking without seeing and seeing without looking.</a> Visual Cogn. 7, 191-211 (2000).</li><li>Levin, D. T., Momen, N., Drivdahl, S. B., Simons, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+blindness+blindness:+The+metacognitive+error+of+overestimating+change-detection+ability.">Change blindness blindness: The metacognitive error of overestimating change-detection ability.</a> Visual Cogn. 7, 397-412 (2000).</li><li>Regan, J. K., Rensink, R. A., Clark, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change-blindness+as+a+result+of+''mudsplashes.">Change-blindness as a result of ''mudsplashes.</a> Nature. 398, 34 (1999).</li><li>Eramudugolla, R., Irvine, D. R. F., McAnally, K. I., Martin, R. L., Mattingley, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Directed+attention+eliminates+'Change+deafness'+in+complex+auditory+scenes.">Directed attention eliminates 'Change deafness' in complex auditory scenes.</a> Curr. Biol. 15, 1108-1113 (2005).</li><li>Gallace, A., Tan, H. Z., Spence, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+failure+to+detect+tactile+change:+a+tactile+analogue+of+visual+change+blindness.">The failure to detect tactile change: a tactile analogue of visual change blindness.</a> Psychon. Bull. Rev. 13, 300-303 (2006).</li><li>Reid, P. J., Shettleworth, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Detection+of+cryptic+prey:+search+image+or+search+rate?.">Detection of cryptic prey: search image or search rate?.</a> J. Exp. Psychol. Anim. B. 18 (3), 273-286 (1992).</li><li>Cook, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dimensional+organization+and+texture+discrimination+in+pigeons.">Dimensional organization and texture discrimination in pigeons.</a> J. Exp. Psychol. Anim. B. 18, 354-363 (1992).</li><li>Shimp, C. P., Friedrich, F. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Behavioral+and+computational+models+of+spatial+attention.">Behavioral and computational models of spatial attention.</a> J. Exp. Psychol. Anim. B. 19 (1), 26 (1993).</li><li>Fremouw, T., Herbranson, W. T., Shimp, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Priming+of+attention+to+local+or+global+levels+of+visual+analysis.">Priming of attention to local or global levels of visual analysis.</a> J. Exp. Psychol. Anim. B. 24 (3), 278 (1998).</li><li>Cavoto, K. K., Cook, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cognitive+precedence+for+local+information+in+hierarchical+stimulus+processing+by+pigeons.">Cognitive precedence for local information in hierarchical stimulus processing by pigeons.</a> J. Exp. Psychol. Anim. B. 27, 3-16 (2001).</li><li>Maki, W. S., Leith, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shared+attention+in+pigeons.">Shared attention in pigeons.</a> J. Exp. Anal. Behav. 19 (2), 345-349 (1973).</li><li>Herbranson, W. T., Fremouw, T., Shimp, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+randomization+procedure+in+the+study+of+categorization+of+multidimensional+stimuli+by+pigeons.">The randomization procedure in the study of categorization of multidimensional stimuli by pigeons.</a> J. Exp. Psychol. Anim. B. 25, 113-134 (1999).</li><li>Wright, A. A., Katz, J. S., Magnotti, J., Elmore, L. C., Babb, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testing+pigeon+memory+in+a+change+detection+task.">Testing pigeon memory in a change detection task.</a> Psychon. Bull. Rev. 17 (2), 243-249 (2010).</li><li>Gibson, B., Wasserman, E., Luck, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Qualitative+similarities+in+the+visual+short-term+memory+of+pigeons+and+people.">Qualitative similarities in the visual short-term memory of pigeons and people.</a> Psychon. Bull. Rev. 18 (5), 979 (2011).</li><li>Elmore, L. C., Magnotti, J. F., Katz, J. S., Wright, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+detection+by+rhesus+monkeys+(Macaca+mulatta)+and+pigeons+(Columba+livia).">Change detection by rhesus monkeys (Macaca mulatta) and pigeons (Columba livia).</a> J. Comp. Psychol. 126 (3), 203-212 (2012).</li><li>Hagmann, C. E., Cook, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Active+change+detection+by+pigeons+and+humans.">Active change detection by pigeons and humans.</a> J. Exp. Psychol. Anim. B. 39 (4), 383-389 (2013).</li><li>Leising, K. J., Elmore, L. C., Rivera, J. J., Magnotti, J. F., Katz, J. S., Wright, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Testing+visual+short-term+memory+of+pigeons+(Columba+livia)+and+a+rhesus+monkey+(Macaca+mulatta)+with+a+location+change+detection+task.">Testing visual short-term memory of pigeons (Columba livia) and a rhesus monkey (Macaca mulatta) with a location change detection task.</a> Anim. Cognition. 16 (5), 839-844 (2013).</li><li>Herbranson, W. T., Jeffers, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pigeons+(Columba+livia)+show+change+blindness+in+a+color+change+detection+task.">Pigeons (Columba livia) show change blindness in a color change detection task.</a> Anim. Cognition. 20 (4), 725-737 (2017).</li><li>Herbranson, W. T., Davis, E. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+display+timing+on+change+blindness+in+pigeons+(Columba+livia).">The effect of display timing on change blindness in pigeons (Columba livia).</a> J. Exp. Anal. Behav. 105 (1), 85-99 (2016).</li><li>Herbranson, W. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+blindness+in+pigeons+(Columba+livia):+The+effects+of+change+salience+and+timing.">Change blindness in pigeons (Columba livia): The effects of change salience and timing.</a> Front. Psychol. 6, 1109 (2015).</li><li>Herbranson, W. T., Trinh, Y. T., Xi, P. M., Arand, M. P., Barker, M. S. K., Pratt, T. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+detection+and+change+blindness+in+pigeons+(Columba+livia).">Change detection and change blindness in pigeons (Columba livia).</a> J. Comp. Psychol. 128 (2), 181-187 (2014).</li><li>Poling, A., Nickel, M., Alling, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Free+birds+aren't+fat:+Weight+gain+in+captured+wild+pigeons+maintained+under+laboratory+conditions.">Free birds aren't fat: Weight gain in captured wild pigeons maintained under laboratory conditions.</a> J. Exp. Anal. Behav. 53 (3), 423-424 (1990).</li><li>National Institute of Mental Health. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Methods and welfare considerations in behavioral research with animals: Report of a National Institutes of Health workshop (NIH Publication No. 02-5083). , (2002).</li><li>Brown, P. L., Jenkins, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Autoshaping+of+the+pigeon's+keypeck.">Autoshaping of the pigeon's keypeck.</a> J. Exp. Anal. Behav. 11, 1-8 (1968).</li><li>Smilek, D., Eastwood, J. D., Merikle, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Does+unattended+information+facilitate+change+detection?.">Does unattended information facilitate change detection?.</a> J. Exp. Psychol. Hum. Percept. Perform. 26, 480-487 (2000).</li><li>Herbranson, W. T., Call, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+and+divided+attention+in+comparative+psychology.">Selective and divided attention in comparative psychology.</a> APA handbook of comparative psychology. , 183-201 (2017).</li></ol>

The method presented here is inspired by the so-called &#34;flicker paradigm&#34; commonly used by cognitive psychologists to study change blindness in humans9. In this human research, change blindness is operationally defined as the impairment in change detection produced by the presence of an ISI that interrupts transitions between stimulus displays. The same is true for the pigeon implementation described here. Furthermore, humans tend to approach the flicker task using a serial search strategy...

Cognitive psychology has repeatedly demonstrated striking and often surprising imperfections in our own cognitive processes. Some of the more notable examples include but are not limited to false memories1, suboptimal decision heuristics2, and faulty statistical reasoning3. A more recent addition to this list is the phenomenon of change blindness. Change blindness is a consistent failure of attention, in which one fails to notice even prominent changes to one&#39;s environment. In one demonstration4, experimenters had a confederate approach individuals to request directions. During their conversation, workers carrying a door passed between the two, briefly interrupting visual contact and providing an opportunity to swap out the confederate for a different person. After this surreptitious exchange, most individuals failed to notice that their conversation partner was no longer the same person. This failure is surprising because moment-to-moment changes would seem to be signals of potentially important events that ought to draw our attention.
In order to better understand how and why change blindness occurs, researchers have brought it into the lab and developed several ingenious procedures5,6,7,8 for studying it under more controlled conditions. One particularly successful approach has been dubbed &#34;the flicker task&#34;9. In this procedure, the experimenters edited photographs by removing a feature, and then presented the images to participants, rapidly alternating between the original and modified versions. Participants quickly spotted the differences. However, if a brief blank field was inserted between consecutive images (producing a flickering display for which the procedure is named) change detection was much more difficult, resulting in worse accuracy and slower response times. This procedure is appealing because it provides a precise measure of change blindness, and it is easy to manipulate specific aspects of the display such as the size, salience, or timing of a change.
The flicker paradigm has proven to be a powerful tool for learning about perception and attention in humans10. The effect is surprisingly powerful and persistent. Change blindness can occur for changes to the only object in a simple animation11, and when looking directly at a change location12. Even experience with change blindness and awareness of the phenomenon does not eliminate it13. Furthermore, change blindness is quite diverse, and can be induced by a number of different events, such as eye saccades5, mudsplashes14, motion picture cuts7, or visual occlusion4. A parallel phenomenon occurs in auditory15 and tactile16 modalities, indicating that it may not be exclusive to visual stimuli and may be a more general phenomenon of attention.
Humans of course, are not the only animal that makes use of attention. Pigeons, for example, show many of the same attentional abilities that humans do. They can select specific features for preferential processing (as when they use a search image to find specific food targets)17,18. They can direct attention toward specific regions or spatial locations19. They can shift their attention between hierarchical levels of organization20,21. They can also divide attention between different aspects of a stimulus display22,23. It seems then, that pigeons possess many of the same abilities that make attention useful for humans. If change blindness has to do with some of the inherent limitations of attention, we might expect to see a parallel change blindness effect in pigeons (and perhaps other animals). Furthermore, there have recently been multiple successful studies of change detection conducted using pigeons, implementing widely varying methods24,25,26,27,28.
Recent research29,30,31,32 has adapted the flicker paradigm to investigate change blindness in pigeons, and has produced results that parallel human change blindness. The current report describes a simple method for implementing this procedure in an operant chamber. As with human versions of the task, it is easy to isolate and manipulate specific aspects of stimulus presentation in order to investigate their influence over change detection and change blindness. Thus, the procedure should constitute a valuable tool for research on the limitations of avian attention, and the extent to which they are similar to the limitations of human attention.

<table>
	<tbody>
		<tr>
			<td>Small Environment Cublicle</td>
			<td>BRS/LVE</td>
			<td>SEC-002</td>
			<td></td>
		</tr>
		<tr>
			<td>Pigeon Intelligence Panel</td>
			<td>BRS/LVE</td>
			<td>PIP-016</td>
			<td></td>
		</tr>
		<tr>
			<td>Grain Feeder</td>
			<td>BRS/LVE</td>
			<td>GFM-001</td>
			<td></td>
		</tr>
		<tr>
			<td>Pigeon Pecking Key</td>
			<td>BRS/LVE</td>
			<td>PPK-001</td>
			<td></td>
		</tr>
		<tr>
			<td>Stimulus projector</td>
			<td>BRS/LVE</td>
			<td>IC-901</td>
			<td></td>
		</tr>
		<tr>
			<td>LED Lamp</td>
			<td>Martek Industries, Cherry Hill NJ</td>
			<td>1820</td>
			<td></td>
		</tr>
		<tr>
			<td>I/O module</td>
			<td>Acces IO</td>
			<td>USB-IDIO-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Personal Computer</td>
			<td>Dell</td>
			<td>Optiplex 3040</td>
			<td></td>
		</tr>
		<tr>
			<td>Visual C++</td>
			<td>Microsoft</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>White Carneau pigeons</td>
			<td>Double-T Farm</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

a method for investigating change blindness in pigeons (columba livia)

Change blindness is a phenomenon of visual attention, whereby changes to a visual display go unnoticed under certain specific circumstances. While many laboratory procedures have been developed that produce change blindness in humans, the flicker paradigm has emerged as a particularly effective method. In the flicker paradigm, two visual displays are presented in alternation with one another. If successive displays are separated by a short inter-stimulus interval (ISI), change detection is impaired. The simplicity of the procedure and the clear, performance-based operational definition of change blindness make the flicker paradigm well-suited to comparative research using nonhuman animals. Indeed, a variant has been developed that can be implemented in operant chambers to study change blindness in pigeons. Results indicate that pigeons, like humans, are worse at detecting the location of a change if two consecutive displays are separated in time by a blank ISI. Furthermore, pigeons&#39; change detection is consistent with an active, location-by-location search process that requires selective attention. The flicker task thus has the potential to contribute to investigations of the dynamics of pigeons&#39; selective spatial attention in comparison to humans. It also illustrates that the phenomenon of change blindness is not exclusive to humans&#39; visual perception, but may instead be a general consequence of selective attention. Finally, while the useful aspects of attention are widely appreciated and understood, it is also important to acknowledge that they may be accompanied by specific imperfections such as change blindness, and that these imperfections have consequences across a wide range of contexts.

The primary result of interest is the difference in accuracy between trials with and without an ISI. In particular, the operational definition of change blindness in the flicker paradigm is significantly reduced change-detection accuracy on trials with an ISI relative to trials without an ISI. This effect can be seen in Figure 3, which shows previously published data29. In that experiment, pigeons detected changes to stimuli consisting...

Watch this Scientific Journal Video about A Method for Investigating Change Blindness in Pigeons Columba Livia at JoVE.com

A Method for Investigating Change Blindness in Pigeons Columba Livia

Change blindness is a phenomenon of visual attention, whereby changes to a visual display go unnoticed under certain specific circumstances. This protocol describes a variation on the flicker paradigm for investigating change blindness that is appropriate and effective for research with pigeons.

A Method for Investigating Change Blindness in Pigeons (Columba Livia)

Change blindness is a phenomenon of visual attention, whereby changes to a visual display go unnoticed under certain specific circumstances. While many ...

This method can help us answer key questions in comparative cognition, such as do pigeons show the same puzzling failures of attention that humans do, and if so, why? The main advantage of this technique is that it can be easily implemented in the standard operant chambers that have been used by behavioral and comparative psychologists for decades. This section described how to train pigeons to peck at stimuli in an operant chamber and accept a reward from the food hopper.At the beginning of each day's session, weigh the pigeons and place them in the operant chambers. The operant chamber is under computer control, with a temporal resolution and response time of less than one millisecond. Run the pretraining sessions daily, and run 100 trials per session.For each trial, randomly select a stimulus element and one of the three keys. Then, illuminate the element on the key using a fast LED source for onset with one millisecond and a clear visual presentation. When the pigeon pecks at the key illuminated by the stimulus, set the stimulus to clear and the grain hopper to open for two to three seconds.Naive and less experienced pigeons may need hand shaping or auto shaping to learn to respond, but experienced pigeons will likely be very quick to peck stimuli. After 100 trials, end the session. Remove the pigeons from the chambers, weigh them, and then return them to their home cages.Between sessions, adjust the bird's food access time to maintain their running weights to 80 to 85%of their free-feeding weight. Continue the pretraining sessions until the pigeons respond quickly and consistently to all of the experimental stimuli to be used, presented on any of the three keys. For the training sessions, program the stimulus display using the experimental control software.Several variables must be set. For the ISI in this example, it is set as 250 or zero milliseconds. For the number of stimuli repetitions, have values of one, two, four, eight or 16 be randomly selected for each trial.Next, for each response key, define an original stimulus display consisting of one or more elements made up of the colors or lines presented during the pretraining sessions. Then, define the change as an addition, deletion or alteration of just one of the display elements on just one key. Next, program the inter-trial intervals to be five seconds with house lights on and all the response keys dark.A stimulus repetition consists of the following sequence. First, a 250 millisecond presentation of the original display. Second, and ISI of the selected length.Third, the modified display for 250 milliseconds. Fourth, another ISI of the selected length. During the repetitions, all key pecks are ignored.Afterwards, immediately illuminate all of the response keys with white light and record the first peck on a response key as the only valid response for the trial. If a bird's response was on the key that displayed a change, provide access to grain from the food hopper for two to three seconds. Otherwise, signal an incorrect response by switching the house lights on and off every half-second for 10 seconds.Run a total of 100 trials per session and run the sessions daily. Maintain the pigeons at around 85%of their free running weight. Maintain the training regime until the pigeon's responses are stable and better than chance.Using the flicker paradigm as presented, there was a measurable difference in accuracy with and without an interstimulus interval. Accuracy was significantly reduced when a 250 millisecond ISI was used. With or without the ISI, accuracy significantly increased with the number of repetitions.In an experiment that manipulated the timing of stimulus displays, there was no change blindness effect with a 30-millisecond presentation and a 15-millisecond ISI. During the same experiment, when presentation and ISI durations were doubled, the change blindness effect returned. There was again a difference in accuracy between trials with and without the interstimulus interval, indicating that display timing influences change blindness.The idea for this method comes from the flicker task, used to investigate change blindness in humans. The method is precise and translates well into an operant chamber. Generally, individuals new to this method might struggle, because it can take extensive training before birds reach an acceptable level of accuracy.Be patient. While attempting this procedure, it's important to monitor pigeons'daily progress and be patient. They'll begin with chance accuracy and improve through trial and error learning.Following this procedure, various aspects of stimulus presentation can be manipulated in order to investigate factors such as the importance of change timing, salience and spatial location. The implications of this technique may extend toward a deeper understanding of attention disorders. The pigeons show us that imperfections of selective attention are not uniquely human and thus may hold some evolutionary significance.

a-method-for-investigating-change-blindness-in-pigeons-columba-livia

Research

JoVE Journal

Behavior

6.3K ビュー.  Whitman College. This method can help us answer key questions in comparative cognition, such as do pigeons show the same puzzling failures of attention that humans do, and if so, why? The main advantage of this technique is that it can be easily implemented in the standard operant chambers that have been used by behavioral and comparative psychologists for decades. This section described how to train pigeons to peck at stimuli in an operant chamber and accept a reward from the food hopper.At the beginn...