Poster Session I - Thursday Evening
P1 Paul Graham (University of Sussex) & Ken Cheng (Macquarie University)
Which Portion of the Natural Panorama is Used for View Based Navigation in the Australian Desert Ant?
Ants that forage in visually cluttered environments use panoramic visual landmarks for guidance and place recognition. Here we ask which portions of natural visual scenes are essential for visually-guided navigation in the Australian desert ant Melophorus bagoti, whose foragers navigate through a habitat containing grass tussocks, shrubs and trees. We captured M. bagoti foragers after they had returned to their nest from a feeder, but before they had entered their nest, and tested their ability to home accurately from a series of release locations. Results show that the lower portion of the visual panorama is more important for accurate visually guided homing than the upper portion. Analysis of panoramic images suggest that important visual information is provided by the panoramic contour, where terrestrial objects contrast against sky.
P2 Michael F. Brown & Toni-Moi N. Prince (Villanova University)
Going My Way?: Similarity of Rat Foraging Partners’ Spatial Choices is Produced by Social Influence
Several sets of experiments completed in our laboratory show a relationship between the choices made by one rat in the radial arm maze and choices made by a second rat simultaneously making choices in the same maze.   Under some conditions, rats are less likely to visit locations that were previously visited by the other rat (an inhibitory effect).  Under other conditions, rats are more likely to visit locations that were previously visited by the other rat (a facilitative effect).  We have interpreted both effects in terms of social memory for the choices made by another rat.   However, it is possible to explain the apparent facilitative effect as resulting simply from the two rats having common preferences for arms of the maze.   Here we present evidence that social memory is necessary to explain the facilitative effect.
P3 Matthew Keller & Michael F. Brown (Villanova University)
Observe, Remember, Avoid? Social Spatial Memory in a Foraging Task

Social spatial memory refers to the ability of an animal to remember the locations visited by another animal within a group. This experiment tested the ability of rats (Rattus norvegicus; focal rat) to remember the locations visited by a conspecific (another rat) in an open field task. There were two experimental conditions. In one, the focal rat was allowed to observe, but not forage with, the conspecific.  In the other, the focal rat was not allowed to observe the conspecific. In both conditions, the focal rat was allowed to forage in the open field and its choices were coded in terms of whether the location had been chosen by the other rat. The focal rat avoided the locations it observed being visited by the conspecific. However, if the focal rat did not observe the other rat’s visits, it tended to visit the same locations visited by the conspecific.
P4 MB Pesendorfer (University of Nebraska, Lincoln), T Gunhold, L Huber, F Range (University of Vienna)
Social conformity has been suggested as a maintenance mechanism for traditions in non-human animals. After an initial spread by social transmission, a tradition can stabilize by individual habit formation, leading to a uniform group pattern superficially resembling social conformity.
Using a two-action apparatus, we established alternative behavioural patterns in six family groups of wild marmosets (Callithrix jacchus). These groups experienced one technique during a training phase and were later tested with two techniques available. The monkeys maintained the trained method, despite discovering the alternative technique. In three control groups with both methods available, animals with a different preference from the groups majority did not adjust towards the group norm. Rather, animals that discovered both techniques remained with the action with which they were initially successful – habit formation.
P5 Jeffrey R. Stevens (Max Planck Institute for Human Development), Alexandra G. Rosati, & Sarah R. Heilbronner (Duke University)
Expectations and delayed gratification in bonobos
Organisms may discount delayed rewards because the future is uncertain--they may not receive delayed rewards.   Therefore, the expectations that an individual has for the likelihood of receiving the future reward should influence how they respond to delayed payoffs.  Here, we offered bonobos (Pan paniscus) a delayed gratification paradigm in which food slowly accumulated over time.  Once subjects chose to consume the reward, food stopped accumulating.  We tested delayed gratification with a reliable and an unreliable experimenter to vary the subjects' expectations.  Subjects showed higher discounting for the unreliable experimenter, with individual differences across subjects.  These data suggest that the expectations generated about the reliability of receiving future rewards strongly influence how individuals value the future.
P6 Roger K. R. Thompson (Franklin & Marshall College) & Timothy M. Flemming (Georgia State University)
Analogical reasoning and the differential outcome effect: Getting a conceptual feel
Rhesus monkeys completed a standard relational matching to sample (RMTS) paradigm infused with a differential reward (pellet ratio) and/or punishment (timeout ratio) system. Monkeys in the reward- and punishment-only conditions performed according to chance. Monkeys in the both condition, however, achieved and overall accuracy significantly greater than chance. In post tests, with the contingencies removed of any differential outcome, all monkeys returned to performing at levels consistent with chance. We posit that these differential reward and punishment systems, when salient enough, allowed for the emergence of an analogical rule. That the monkeys did not retain an analogical rule in post tests without differential outcomes in place likely means that their behavior was implicit, due to what we call a “conceptual feel.”
P7 Michael J. Beran (Georgia State University)
Judgments of Continuous and Discrete Quantities by Chimpanzees
Chimpanzees compared two amounts of poured liquids, using a variety of presentation methods, and performance was compared to other experiments with discrete quantities. First, chimpanzees compared two clear containers holding differing amounts of juice. Next, they compared different quantities that were dispensed from opaque syringes held 12 inches above opaque containers. Then, one quantity was poured it into an opaque container whereas the other quantity was visible in a clear container. Finally, the heights at which the opaque syringes were held above opaque containers differed for each set, so that sometimes sets with smaller amounts of juice were dropped from a greater height providing a possible visual illusion as to the total amount. In all cases, chimpanzees exceeded chance levels of performance, although performance was lower than in some previous experiments with discrete quantities.
P8 Thomas E. Welch & Micheal L. Dent (University at Buffalo, SUNY)
The effects of time and intensity on the auditory Franssen Effect illusion in birds and humans
The Franssen Effect (FE) has been characterized in humans, cats, and more recently in birds.  To elicit the FE, listeners are presented with a signal comprised of two simultaneously-presented, spatially separated components: a transient component with an abrupt onset and ramped offset, and a sustained component with a slowly rising onset and longer overall duration. When the FE is operating, the perception is that of a single long-duration steady state tone at the location of the transient component, even though the sound is no longer there.  The current experiments manipulated aspects of time and intensity of the two stimuli to more precisely determine the influence of these parameters on the incidence of the FE in humans, zebra finches, and budgerigars.  Some manipulations strengthened the illusion, while others reduced it. 
P9 Wenyi Zhou & Jonathon D. Crystal (University of Georgia)
Episodic-like Memory: Rats Know “When” Based on Time of Day
Roberts et al. (2008) argued that episodic-like memory in rats is different from human episodic memory because rats learned how long ago, rather than remembering when, an event occurred. To facilitate memory for when an event occurred, we eliminated how-long-ago cues. Rats completed study-test trials in a radial maze, with 2-min retention intervals; one randomly selected location in the study phase provided chocolate. Chocolate locations replenished in the test phase in the morning (7 am) or afternoon (1 pm), counterbalanced across rats. Chocolate revisits tracked the replenishment contingency (Exp 1). We advanced light onset by 6 h and conducted a test in the morning to put in conflict time of day and time since light onset. The rats treated the phase-shift test as a ‘morning’ trial, suggesting the use of a circadian oscillator (Exp 2). Discrimination of what-where-when was based on time of day.
P10 Julia E. Meyers-Manor and J. Bruce Overmier (University of Minnesota)
Remember When: The Search for Episodic-like Memory in Pigeons
Controversy over the ability of animals to express episodic memory has led to the search for features of episodic-like memory in animals; common tests involve remembering an event in terms of what happens, where it happens, and when it happens. Evidence for the ability of animals to show episodic-like memory has been increasing.  Here, pigeons were tested in an operant paradigm in which they had to recall which keys to peck in order to get two types of food.  They also had to track how long ago they had previously been tested (1 hour or 4 hours prior) in order to determine whether the food was good to eat or was bad from being covered in soap ("rotten").  Pigeons showed the ability to track foods that "rotted" over time as well as foods that "ripened" over time to accurately peck the key that previously produced good food based on how long ago they experienced that food in the chamber.
P11 Dale N. Swanton & Matthew S. Matell (Villanova University)
Characterization of temporal averaging using single-trials analysis
Rats were trained using a two-duration peak-interval procedure, in which one modal stimulus (e.g. tone) predicted reward availability following an 8s delay and another modal stimulus (e.g. light) predicted reward availability following a 24s delay.  Stimuli/duration relations were counterbalanced producing a tone-short group and a light short-group. When presented with a tone/light compound stimulus in extinction, tone-short rats exhibited behavior equivalent to temporal averaging (Swanton, Gooch & Matell, 2008).  Conversely, light-short rats produced a non-scalar, asymmetrical response distribution, inconsistent with temporal averaging.  We attempt to characterize the nature of this responding by analyzing data from individual trials using a standard single-step function, a multi-step function and a cumulative rate algorithm (Gallistel et al, 2004).
P12 Allie Kurti & Matthew Matell (Villanova University)
Modality Effects in a Delay Discounting Task
Previous research has demonstrated a modality effect for clock-speed in rats and humans (e.g., tones drive an internal clock faster than lights). As a consequence, auditory stimuli appear longer than visual stimuli (e.g., Wearden et al., 1998).  The present research examines whether this modality effect produces a difference in the rate of delay discounting. In an adjusting delay procedure, rats choose between a standard duration providing one food pellet and a longer, adjusting duration providing two. The indifference point (i.e., the delay when standard and adjusted durations are chosen with equal frequency) provides a measure of temporal discounting, and will be assessed using standard durations of 1, 2, 4, 8, and 16 seconds to calculate hyperbolic delay curves. We will examine whether the rate of discounting is influenced by the modality of the standard and/or adjusting delay.
P13 Tiffany Galtress (University of York, U.K.) & Kimberly Kirkpatrick (Kansas State University)
Reinforcer Magnitude Effects on Temporal Discrimination.
Rats were trained on a temporal discrimination procedure with a single food pellet delivered for responding correctly to a short or long duration signal. Following training, testing with a range of novel durations produced a psychophysical function relating the probability of long response to test duration. Increasing the reward to four food pellets on either the short or long duration, while maintaining the one-pellet reward on the alternative duration produced a flattening of the psychophysical function. This disruption in temporal discrimination is discussed in terms of response bias and the effects of motivation on stimulus control.
P14 Neil McMillan and Bill Roberts (University of Western Ontario)
Blocking and Overshadowing Effects on Timing in Pigeons
The effects of cue competition on timing were studied in both overshadowing and blocking operant procedures.  A white center key delivered reward when pecked 30 s after a red side key was presented, and 10 s after presentation of a green side key on the other side.  In Experiment 1, key presentations were concurrent during training trials for overshadow-condition pigeons, while side key presentations were separated across training trials for control birds.  In Experiment 2, blocking was studied by preexposing experimental pigeons to either red or green side key training trials prior to training with concurrent stimuli.  Peak time curves were compared between experimental and control conditions.  The findings revealed evidence for blocking of timing accuracy but no evidence for overshadowing of timing accuracy.
P15 Cody W. Polack, Heather T. Sissons, & Ralph R. Miller (SUNY-Binghamton)
Determinants of the Overexpectation Effect
Three conditioned suppression experiments with rats were conducted to determine if trial spacing influences the overexpectation effect.  Massing of reinforced trials with elemental stimuli impaired responding (trial massing effect) as did reinforced spaced trials of the target cue in the company of another conditioned excitor (overexpectation).  Alternatively, massed reinforced trials of the compound stimulus produced less of a decrement than either of these decremental treatments alone.  This effect was observed in both first-order conditioning and in sensory preconditioning.  Subsequent extinction either of the companion stimulus or the training context found that these effects are mediated in part by the associative status of the training context at the time of testing.
P16 Regina Paxton and Robert R. Hampton (Emory University)
Choice by mutual exclusivity in rhesus macaques (Macaca mulatta)
Mutual exclusivity is the ability to associate a novel word with a novel object presented among familiar objects. It has been suggested that this skill is limited to word learning in humans, but evidence from nonhumans suggests it may occur in other contexts. In the present study, monkeys learned four stimulus-stimulus (S-S) associations. On two types of test trials three images from the known S-S pairs and one novel image were presented as comparisons. On exclusivity trials, the sample was a novel image and monkeys were required to select the novel comparison image. On control trials, the sample was a known image and monkeys were required to select its known associate. Monkeys learned to select the novel comparison image only on exclusivity trials, suggesting choice by mutual exclusivity. Additional experiments evaluated whether choice by exclusivity facilitated learning new S-S pairs.
P17 Caroline G. Strang, Leigh C. P. Botly, & Eve De Rosa (University of Toronto)
Probing Inhibitory Control in Rats
Two important components of inhibitory control are the ability to suppress: (1) a prepotent response and (2) processing of a task-irrelevant stimulus. These distinct inhibitory abilities are confounded in standard measures of inhibitory control, such as reversal learning. We examined the contributions of these two components in rats using conditional simultaneous odour discriminations in a within-subject design. A response reversal task required both inhibiting a prepotent response and responding to a previously task-irrelevant stimulus. A proactive interference task required inhibiting a prepotent response and responding to a novel stimulus. A learning-to-ignore task required responding to a previously task-irrelevant stimulus without any prepotent response inhibition. Although rats showed negative transfer in all conditions, it was greatest when inhibition of a prepotent response was required.
P18 Aya Hashimoto & Sadahiko Nakajima(Kwansei Gakuin University)
Contextual control of rats' conditioned taste aversion based on wheel running
Wheel running endows rats with conditioned aversion to a paired taste (see Boakes & Nakajima, 2008, for a review). This paper presents a successful demonstration of contextual control over such a running-based taste aversion in male Sprague-Dawley rats. In one physical context (e.g., a dark-silent room) a 15-min access to a salt-MSG solution was followed by a 30-min voluntary wheel running, while in the other context (e.g., a lighted-noisy room) the same solution was presented without the wheel running. Consumptions in these contexts were differentiated over the training days to show smaller intake in the running context than in the non-running context. Post-training manipulations including context extinction and transfer tests with another taste revealed that both occasion setting and simple context-running association were involved in the mechanism of this contextual control effect. Another intriguing finding of this research is that Wistar rats did not show robust evidence of contextual control.
P19 Takatoshi Nagaishi, Sadahiko Nakajima, & Madoka Nakanishi (Kwansei Gakuin University)
Overshadowing of rats' conditioned taste aversion based on wheel-running
In many Pavlovian conditioning preparations, conditioned responding to a target stimulus could be attenuated if the target stimulus were reinforced in compound with another stimulus (associative overshadowing). The present study demonstrated overshadowing of conditioned taste aversion by another taste in two experiments with wheel running as the aversion-inducing agent. Training rats with serial presentations of two taste solutions before confinement in an activity wheel (X -> A -> running) resulted in weak aversion to taste X, compared to the training procedure without presentation of A. This overshadowing effect was shown by an overnight one-bottle test in Experiment 1 and by daily 15-min two-bottle (X vs. water) tests in Experiment 2. Such an overshadowing effect has been reported in other Pavlovian conditioning preparations including poison-based taste aversion learning. Thus, the demonstration of overshadowing effect in this study provides another similarity between running-based taste aversion learning and other Pavlovian conditioning preparations.
P20 Tori Vratanina, Desiree Sharpe, & Irwin Bernstein (University of Georgia)
Quantity Discrimination and Token Summation in Western Lowland Gorillas
Gorillas are able to perform successfully on quantity discrimination and summation tasks involving primary reinforcement. Other primate species have demonstrated the capacity for quantity discrimination and summation with secondary reinforcement in the form of tokens (e.g., token A = 1 reward, token B = 3 rewards). We examined this capacity in nine gorillas. Six of the nine gorillas were able to successfully make quantity discriminations with tokens. Data collection is ongoing for the summation phase of the experiment, which only two of the six gorillas have reached at this time. Preliminary data analysis indicates that these two subjects are performing successfully at the summation task (i.e., are choosing the larger sum of two choices above chance). We expect similar performances from the remaining subjects. 
P21 Shannon M. A. Kundey (Hood College), Andres De Los Reyes (University of Maryland, College Park), & Chelsea M. Taglang (Hood College)
Humans’ Learning of Structured vs. Unstructured Subpatterns within a Random Subpattern
Recent evidence showed rats learned a structured (12345678) but not an unstructured subpattern (17356428) interleaved with responses on randomly presented levers (X) in a circular array: 1X2X3X4X5X6X7X8X or 1X7X3X5X6X4X2X8X. This suggests the rule-based nature of nonadjacent elements aided superior pattern learning even when the rule relating them was motor response independent. However, structured rats’ learning was slower than expected based on studies using structurally more complex patterns. Here, we explored humans’ performance in an analogous computer-based task using the same interleaved patterns. With a mouse, humans chose spatial locations in a circular array in proper sequential order. Like rats, only the structured group learned their pattern and learning was slower than expected. 
P22 Mario A. Laborda, James E. Witnauer, & Ralph R. Miller (State University of New York – Binghamton, USA)
Contrasting overexpectation and extinction
Three conditioned suppression experiments with rats compared overexpectation and extinction.  Experiment 1 replicated the basic overexpectation effect, responding in Group Overexpectation (which was exposed to reinforcement of X in compound with another excitor) was reliably less than responding in Group Control (which was merely exposed to further reinforcement of X in the presence of a neutral stimulus). Experiment 2 found that extinction was disrupted by context postexposure, whereas overexpectation was unaffected by context postexposure. Experiment 3 indicated that large numbers of extinction trials augment extinction but large numbers of overexpectation trials had no impact on the overexpectation effect. These results are inconsistent with the view that overexpectation and extinction are driven by a common mechanism.
P23 A. George Wilson (University of Georgia), Matthew S. Matell (Villanova University), & Jonathon D. Crystal (University of Georgia)
Mixed Temporal Memories in the Peak-Interval Procedure
The objective was to develop a procedure in which rats mixed short and long temporal memories. The reinforced duration was randomly selected to be either 8 or 21 s at the start of each daily session (8-21 group). For other rats, the duration was always 21 s (21-only group). At the beginning of sessions with 21-s durations, the 8-21 rats produced a peak at approximately 15 s, which was reliably earlier then in the 21-only group; the spread of the response rate distributions were the same, suggesting that the 8-21 group timed the intermediate value in a non-scalar manner. At the end of sessions with 21-s durations, the groups timed 21 s and were indistinguishable. The results suggest that in an ambiguous situation, rats mix temporal memories but then use a single memory when the reinforced duration is apparent.
P24 John F. Magnotti & Jeff S. Katz (Auburn University)
Orientation Feature Binding in Pigeons
Manipulating conditions under which humans search for a target is a standard approach for studying perceptual errors. Conjunction errors occur when participants incorrectly respond "target present" when only parts of the target are present. We adapted a framework from the human perception literature to test for feature binding in a conditional discrimination task. Pigeons responded to a yellow clover in the presence of a plus sign (+) and to a cyan pentagon in the absence of a plus sign (e.g., vertical line, horizontal line). We compared the false alarm rates on trials that contained all parts of the plus sign to trials that did not. The preliminary results of our study place stricter constraints on the conditions under which conjunction errors arise and influence responding.
P25 Sarah Jones, Jessica Cantlon, Monica Carlson, Elizabeth Brannon (Duke University)
Numerical Sensitivity of Lemurs
Previous work with primates has shown that accuracy in ordinal numerical tasks is modulated by the ratio between two numbers, as predicted by Weber’s Law.  This study was designed to estimate numerical sensitivity in multiple species of lemurs by estimating the Weber fraction (WF).  Blue-eyed black (Eulemur macaco flavifrons), Mongoose (Eulemur mongoz), and Ring-tailed (Lemur catta) lemurs were trained to order the pairs 2-4, 4-8, and 2-8 on a touch-screen and then tested with all possible pairs of the values 1-9.  WFs were estimated with the equation from Pica, et al (2004).  Preliminary results indicate that the WF for lemurs is twice as large as the WF reported for rhesus macaques, and nearly 3 times as large as the WF reported for humans.  Although all species are capable of ordinal numerical judgments, lemurs may form less precise numerical representations than those of monkeys or humans.
P26 Matthew J. Pizzo (Bucknell University), Kimberly Kirkpatrick (Kansas State University), & Pamela Blundell (University of Leeds)
Changes in criterion value alter performance on DRL schedules
The differential reinforcement of low rate (DRL) schedule is commonly used to assess impulsivity, hyperactivity, and the cognitive effects of pharmacological treatments on performance. The DRL schedule requires subjects to withhold responding for a certain amount of time between responses to obtain reinforcement. Often, the DRL criterion time is shifted towards increasingly longer values over the course of training, but the effect of this procedure is poorly understood. Two experiments examined the effects of shifts in DRL criterion. Both an abrupt shift in the criterion and a gradual incremental progression in criterion were compared with longer maintained criteria on different measures of DRL efficiency and inter-response time (IRT) production. The results illustrate that both types of criterion shifts produced deficits in learning a longer DRL criterion. Additionally, this effect was more pronounced with a sudden shift. The combined results argue against using procedures that involve changing the DRL criterion.
P27 Karen E. Doyle & Stephen B. Fountain (Kent State University)
Two New Methods for Studying Serial Pattern Learning in Rats
In a serial multiple-choice (SMC) task like Fountain & Rowan’s (1995), rats learned to choose successive correct positions from a circular array of six nose poke receptacles on one wall. Rats learning a structured pattern showed differential acquisition rates for different elements types. When rats had to make a “start” response for each trial on a receptacle centered in the circular array, the same pattern of results was obtained. In a serial reaction time (SRT) task in the same apparatus, rats learned to track the shifting position of a light presented as either a structured or unstructured series. Although the groups made similar chunk-boundary and within-chunk errors, rats learned to make fewer errors on a violation element in the structured series compared to the comparable item in the unstructured series.  Differences between results from the SMC and SRT procedures will be discussed.
P28 Joseph Gaspard (University of Florida; Mote Marine Laboratory), Gordon B. Bauer (New College of Florida), Roger Reep (University of Florida), and David Mann (University of South Florida)
The Manatee Audiogram and Auditory Critical Ratios
A behavioral audiogram indicated that manatee auditory frequency detection for tonal stimuli ranged from 0.25 to 90.5 kHz with peak sensitivity extending from 8 to 32 kHz.  Critical ratios, thresholds for tone detection in the presence of background masking noise, were determined with one-octave wide noise bands, 7 – 12 dB (spectrum level) above the thresholds determined for the audiogram under quiet conditions.  Manatees appear to have quite low critical ratios, especially at 8 kHz.  This suggests that manatee hearing is sensitive in the presence of background noise, which also suggests that they have relatively narrow filters in this frequency range. Interestingly, many manatee vocalizations are tonal harmonic complexes that often include a tonal component in the 4-8 kHz range.
P29 Laura R. G. Pickens & Stephen B. Fountain (Kent State University)
Adolescent Nicotine Exposure Procedures and Adult Rat Serial Pattern Learning
Adolescent nicotine exposure via osmotic pump at 6 mg/kg/day over postnatal days (P) 30-48 produces neurophysiological changes in the brains of adult rats (Trauth et al., 1999). We examined whether nicotine delivered in this manner during adolescence would produce cognitive deficits like those seen after daily injections in a study by Fountain et al. (2008). After adolescent exposure via the osmotic pump method, adult rats learned serial patterns beginning on P95 in the cognitive task of Fountain et al. (2008). Whereas Fountain et al. (2008) found that daily nicotine injections of 1 mg/kg over P25-59 caused impairments in adult rat serial pattern learning, adolescent exposure via osmotic pump did not produce cognitive deficits in adult rats. We will compare these two studies that used the same cognitive paradigm and propose possible reasons for the differing results.
P30 James D. Rowan and Ying (Joy) Tang (Wesleyan College)
The Effects of Phrasing Cue Placement in the Last Chunk of a Perfect Runs Serial Pattern.
Earlier research found that when human subjects learned a violation runs pattern (e.g.  123, 234,…, 818) with a 3s phrasing cue placed at either directly before the violation, the trial before the violation, or 2 trails before the violation, that all 3 groups learned the violation at the same rate but the group that received the cue the trial before the violation performed more poorly on the rest of the pattern.  This experiment examined whether the effect was the result of phrasing cue placement or if there was an interaction between the misplaced cue and the violation.  Subjects learned the same patterns as in the previous experiment but without the violation.  Subjects in all three groups learned the pattern equally well, indicating that the disruption in the previous experiment was an interaction between the placement of the phrasing cue and the violation element.

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Poster Session II - Saturday Evening
P31 Kelly E. Radziwon, Kristie June, Matthew Xu-Friedman, Richard J. Salvi, & Micheal L. Dent (University at Buffalo-SUNY)
Behaviorally Measured Audiograms and Gap Detection Thresholds in Mice
Mice (Mus musculus) have become useful models in the study of hearing, although behavioral studies in these animals are still rare.  We measured audiograms and gap detection thresholds using a Go/No-Go operant conditioning procedure requiring the mice to nose poke for a liquid reward, and the psychophysical Method of Constant Stimuli.  Both experiments yielded consistent between-subject results.  In the audiogram detection task, the mice were sensitive to frequencies ranging from 1 to 48 kHz, with peak sensitivity around 10 kHz.  In the gap detection task, mice showed discrimination thresholds of 1-2 ms for 800 ms broadband noise bursts.  These results add to the wealth of behaviorally-measured comparative data on hearing in mammals.    
P32 Henrike Hultsch (Freie Universitaet Berlin)
Constraints in Song Retrieval in the Singing of Nightingales.
The hierarchical organization of singing by tape-tutored nightingales reflects the organization of auditory input experienced early in life. In particular, birds tend to sequentially associate imitations of those song-types that, as models during the tutoring, were experienced together in a coherent string of stimulus songs . To understand the process of retrieval of acquired songs, I examined the performance length of bouts of imitations developed from tutored song strings of various lengths (range: 3 to 40 songs). Sequentially coherent performances of imitations from shorter song strings (e.g. 3songs) were longer (i.e. contained more song renditions from that string) and those from longer strings (e.g. 40songs) were shorter (i.e. contained less song renditions)than expected from experience of the ’originals’. These findings suggest that retrieval of stored song is constrained by an equivalent to working memory.
P33 Benjamin M Basile, Michael R Ortiz, & Robert R Hampton (Emory University)
Effects of image set size and practice on the serial position curve in rhesus monkeys (Macaca mulatta)
The combination of primacy and recency produces a U-shaped serial position curve typical of memory for lists. Using serial probe recognition, we evaluated the effects of image set size and practice on the serial position curve in rhesus monkeys. Monkeys studied lists of five images on a touchscreen. At test, they saw one image and a “non-match” symbol. They were required to touch the image if it was from the list and the non-match symbol if it was not. In Experiment 1, we tested lists drawn from large, medium, and small sets of images, in that order. We observed primacy only with the latter two, smaller image sets. In Experiment 2, we distinguished between the effects of set size and practice by using the three set sizes concurrently. The role of image familiarity and practice on primacy and recency will be discussed.
P34 Chuck Locurto, Matthew Gagne, & Lauren Nutile (College of the Holy Cross)
Tests of Implicit Chaining in Cotton Top Tamarins (Saguinus oedipus) II
Tamarins were shown a five-element serial chain that consisted of an icon presented at different locations on a touchscreen. Learning the chain’s pattern was not necessary for reinforcement. Tests were conducted following training to determine what the tamarins had learned, two of which were new to this procedure. One new test involved occasionally replacing the training icon with new icons at each serial position. The second test, termed “running start,” gave the tamarins the beginning of the chain (e.g., A->B), and then gave them a choice between the next item in the chain and the subsequent item (C or D). The subsequent item was closer to food in procedures in which food came at the end of the chain. The choice, then, was between the next element in the chain (C) versus one that was temporally closer to food (D).
P35 Lauren Highfill (Eckerd College), David Hanbury, Rachel Kristiansen, Stan Kuczaj, & Sheree Watson (University of Southern Mississippi)
The Use of Personality Assessments in Designing Environmental Enrichment for Garnett’s Bushbabies (Otolemur garnettii)
The personality traits of ten bushbabies were assessed using a variety of behavioral and cognitive tasks. Each subject was also exposed to five different enrichment interventions to assess the relationship between personality and enrichment effectiveness. All interventions improved animal welfare by increasing the frequency of species-typical behaviors, but some forms of enrichment differentially benefited individual subjects based on their personality. For example, after participating in a simple training exercise, subjects which scored high on Openness to Experience significantly decreased their maladaptive behaviors. These results have implications for using personality as a tool for improving the cognitive well-being of animals.
P36 Rebecca Greenberg & Dorothy Fragaszy (University of Georgia)
Decision-Making Strategies of Wild Capuchin Monkeys
Wild bearded capuchin monkeys (Cebus libidinosus) use stone tools to crack open tough palm nuts to ingest the kernel. Optimal foraging theory recognizes alternative strategies that individuals adopt in complex foraging circumstances. Nine monkeys from a well-documented group of wild bearded capuchins were studied over a four-week period in Piauí, Brazil. We gave the monkeys a choice of two nuts differing in resistance and two manufactured stones of same volume but different mass. Other experiments allowed the choice of two manufactured stones with one hard nut so that the choice of stone was more important.  Monkeys consistently selected the nut that was easier to crack and the heavier stone when the stones differed in weight by at least 500 grams. This study suggests that capuchins are sensitive to properties of stones and nuts, as reflected in their choice of materials for cracking nuts.
P37 Radhika Makecha (Stephen F. Austin State University), Stan Kuczaj (University of Southern Mississippi), & Otto Fad (Busch Gardens, Tampa)
An investigation of the use of touch in the social interactions of a group of Asian elephants (Elephas maximus)
Elephants use a variety of sensory modalities to communicate, including touch. However, little is known about the role of touch in their social interactions. The tactile interactions of six Asian elephants were examined to better ascertain how touch is used in social contexts.  Elephants differed in their initiation of general tactile behaviors, as well as in their initiation of aggressive and nonaggressive tactile behaviors, with dominance rank being one of the influencing factors. Further analysis revealed the trunk as the body part playing the largest role during tactile interactions. Touch seems to be an important part of elephant social interactions, but much remains to be discovered about its role in communication.
P38 Anna Wilkinson (University of Vienna) and Kimberly Kirkpatrick (Kansas State University)
Tracking and capture of constant and sinusoidal velocities in pigeons and humans
Pigeons and humans were trained on identical motion-tracking and capture tasks using a touch screen apparatus. A 0.5-cm yellow circle entered the viewing screen and moved directly across on either a horizontal or vertical path. The mean speed was 3.4 cm/s and could either be a constant velocity or a sinusoidal velocity which varied systematically over the motion path. Both pigeons and humans were slightly worse at capturing a sinusoidal velocity, but both species were able to learn to capture both types of motion. On special test trials where the stimulus suddenly and unpredictably stopped, both species made many errors and demonstrated an “overshoot” effect in which their errors were in front of the target position. This indicates that both species were anticipating ahead of both the constant and the sinusoidal velocities. The results suggest general similarities in the tracking and capture of motion by humans and pigeons.
P39 Jessica Crast (University of Georgia)
A Pilot Study of the Social Facilitation of Foraging Activity
Capuchin monkeys (Cebus apella) are social foragers that specialize on embedded foods. Young capuchins require years of practice before reaching adult foraging proficiency. I propose that foraging activity is socially facilitated and that the social facilitation of practice contributes to learning foraging skills. Thus, during several 10-minute sessions I presented eight adult male capuchins with a foraging task and recorded latencies to make contact with and solve the task, duration of investigative contact prior to first solve, and overall duration of movement of the functional parts of the task. Subjects were divided into two groups: Alone (four subjects were presented with the task alone) and Social (four subjects were presented with the task in the presence of a working partner). Results show that subjects in the Social group contacted and solved the task faster than subjects in the Alone group.
P40 Tamra Beckman, Jennifer Vonk (University of Southern Mississippi) & Stephanie Jett (University of South Alabama)
Cognitive Dissonance in Birds
Six members of the parrot (Psittacinae) family were presented with a cognitive dissonance paradigm modeled after Egan Santos & Bloom (2007). In experimental trials subjects were given choices between two equally preferred food items. In control trials subjects were presented with one accessible and one inaccessible option from another triad of equally preferred food items. Next, the unchosen or previously inaccessible item and a novel equally preferred item were presented. The birds showed no significance preference for the novel versus the unchosen option on experimental trials, suggesting that they did not resolve dissonance by devaluing the unchosen option from previous trials. This result is consistent with a previous study in which monkeys, but not black bears, exhibited cognitive dissonance, which suggests that this phenomenon may be unique to primates.
P41 Tammy L.B. McKenzie & Sierra King (Brandon University)
Do hormones influence categry learning in horses?
It is extremely important to many species to be able to categorize stimuli. Categorization reduces cognitive strain and allows for organisms to organize their world. In nonhuman animals, a substantive amount of research has been done on category learning in pigeons and non-human primates. Despite the plethora of knowledge gained from research conducted with pigeons and non-human primates much still remains to be discovered about category learning in non-human animals, in particular the effects of a wide variety of factors on category learning including androgen levels, pregnancy, etc. The present research, conducted with horses, provides insight into the potential influence of androgen levels on category learning in non-human animals. Stallions performed better on a categorization task than did geldings.
P42 Kara A. Tyler (New College of Florida), Kate M. Chapman (Pennsylvania State University), Caitlin O’Brien (New College of Florida), & Gordon B. Bauer (New College of Florida, Mote Marine Laboratory).
Behavioral Lateralization in the Florida Manatee (Trichechus manatus latirostris)
Limb preferences and scar locations in animals are used to infer lateralization of the brain in many species. The flipper uses of 10 captive and 31 wild Florida Manatees were recorded and analyzed for individual and population-level flipper preferences. The manatees displayed an overall population- level bias for the left flipper. This may indicate underlying hemispheric lateralization. Additionally, 47 watercraft-related scars were analyzed for the side of the body on which they occurred and were found significantly more often on the left side of the body than on the right side of the body or down the center implying possible lateralization of evasion behavior in the manatee.
P43 Hyangsun Chin, Sadahiko Nakajima (Kwansei Gakuin University) & Michihiro Taki (Kobe City Suma Aqualife Park)
Reaction of captive bottlenose dolphins to their mirror images
We exposed five female bottlenose dolphins (Tursiops truncatus) in an aquarium to a mirror for recording their responses with a single-case reversal design over 7 test days (one test day per week). Each test day consisted of three 30-min sessions with the inter-session interval of 60 min. The dolphins could see either a blue acrylic board (the baseline condition) or an acrylic mirror (the mirror condition) attached behind the underwater window of their home pool. The frequency of window-related behaviors (e.g., approaching the window) was higher in the mirror condition than in the baseline condition, suggesting their interest in the mirror. Displaying the food (squid) and tongue-protruding were observed exclusively in the mirror condition. One of them also showed threatening behavior against the mirror. Further research is required to elucidate whether their behaviors reflect self-recognition.

P44 Sarah Benson-Amram*, Alan Bond (Univ. of Nebraska) and Kay Holekamp* (*Michigan State Univ.)
Problem-solving in Captive and Wild Spotted Hyenas
We designed a Thorndike-like puzzle box to study problem-solving in captive and free-living spotted hyenas (Crocuta crocuta).  A rebar box contained meat that hyenas accessed by sliding a bolt.  Overall, captives were more successful at solving the puzzle, and more innovative, than wild hyenas.  Innovation was measured as the number of different exploratory behaviors individuals emitted in their first trial. Five hypotheses might explain difference in success between captive and wild adults.  Higher success among captives might be due to 1) greater motivation, 2) shorter time between trials, 3) more undisturbed time with the box, 4) extra energy or 5) more experience with man-made objects. Hypotheses 1-4 were not supported by our data.  Our results therefore suggest that higher success and innovation among captives may be due to more experience with man-made objects.
P45 Danielle Sulikowski & Darren Burke (Macquarie University)
Movement analyses reveal food-specific search patterns in the omnivorous Noisy Miner bird
In a previous study we allowed noisy miner birds to forage for either nectar or invertebrates in an open-field analogue of the radial arm maze.  Introducing a manipulation that disrupted the birds’ movement had a greater detrimental effect on performance when birds were foraging for invertebrates than when they were foraging for nectar.  In the study reported here, we allowed birds to forage in a larger maze to facilitate more detailed analyses of their movement.  These data show clear differences between the search patterns used by nectar foragers and those used by invertebrate foragers.  These findings lend further support to the notion that a movement-based strategy is used while birds are foraging for invertebrates, while a spatial memory strategy is employed for nectar.
P47 Kosuke Sawa & Yuka Abe (Senshu University)
Effect of landmark salience on spatial learning in hamsters
Many species tend to use spatial landmarks as cues to explore the location of biologically significant goal (e.g., food patch). In present research, we explored the contents of spatial knowledge based on landmarks in Djungarian Hamster (Phodopus sungorus). Search area was round arena and twelve candidates of goal were located on the circumference of arena. During training, two identical landmarks were put on both adjacent sides of goal. In testing, landmarks were moved along circumference. Subjects showed different trends of performance in testing based on the size of landmark used in training, which suggested that landmark salience affected on the contents of spatial knowledge.
P48 Takaaki Kaneko & Masaki Tomonaga (Primate Research Institute, Kyoto University)
Perception of self agency in chimpanzees
We investigated the cognitive capacity of chimpanzees to distinctly recognize the action caused by themselves  from the action caused by the other factors. We used a track ball and a touch panel monitor as input devices. In each trial, two cursors are shown on the display. One is manipulated by the chimpanzees using the track ball and the other is replayed motion of “past action of the same chimpanzee”. The chimpanzees are required to touch the cursor they manipulated. Three chimpanzees participated in this experiment, and successfully discriminated the cursor they moved from the other. Furthermore, the results from one of the chimpanzees can not be attributed to only a simple visual discrimination but a matching between visual feedback and her own action. We are further investigating their specific strategies by focusing on effects of temporal and spatial contingency.
P49 Erin N. Colbert-White, Dorothy Fragaszy, & Betty Jean Craige (University of Georgia)
An African Gray Parrot’s Use of Language to Regulate Social Relationships
Captive African gray parrots bond socially with their human caregivers.  This study examines how one parrot uses language to regulate her social relationship with her owner.  We videotaped the parrot in four social contexts (home alone, owner in the room, owner out of the room but within hearing range, and owner and company present but parrot ignored).  Preliminary results include frequent non-word vocalizations when alone or ignored, phrase choice and placement that are arguably similar to human persistence and persuasion, re-occurring phrases referencing subject and owner location with frequent requests for interaction when owner not in the room, and possible behavioral indications of frustration at being ignored.  These results suggest the subject deliberately uses language as a tool to regulate the owner’s attention and physical proximity.
P50 Frank Fishburn and Toru Shimizu (University of South Florida)
Male Pigeons Discriminate Real-Time and Pre-Recorded Self-Videos
Male pigeons attempt to engage in courtship-like behavior with unfamiliar individuals regardless of sex. Accordingly, we studied whether males react differentially to real-time views of the self compared to pre-recorded views of the self. Subjects reacted strongly to pre-recorded video images of the self and those of unfamiliar males. Their responses were weaker to the real-time views of the self, including mirrored and horizontally or vertically flipped images. The results suggest that they discriminated between the real-time and pre-recorded stimuli. The discrimination might be simply based on certain physical characteristics of the stimuli or the specific behaviors of the stimulus birds at a certain location relative to the subject. It is also possible that the subjects discriminated these stimuli based on congruence with real-time proprioceptive or reafferent signals.
P51 Pierre Blacher, Dominique Fresneau & Elise Nowbahari (UMR CNRS 7153, Université Paris Nord, Villetaneuse, France)
Investigation of individual discrimination and social status capacity of ants Pachycondyla apicalis
In workers of Pachycondyla apicalis, the egg-laying is regulated through the establishment of a dominance hierarchy. Models of social hierarchy suggest that, to avoid costly fights, workers may have developed cognitive abilities to distinguish superior rivals. Indeed, individuals recognize individually each nestmate and/or their corresponding social status. We observed in three queenless colonies, the establishment of the hierarchies in order to determine the rank of each worker. Then we tested the two alternatives using an habituation/discrimination paradigm. Our study does not show an individual recognition of nestmates of P. apicalis workers, but clearly demonstrates that they can discriminate their social and reproductive status. Therefore, within the scope of a reproductive hierarchy, such capacity may have evolved to reduce costly conflicts among workers, thus enhancing colony efficiency.
P52 Lisa K Son (Barnard College), Gin Morgan, Tamar Kornblum (Columbia University), Damian K. Scarf (University of Otago), & Herbert Terrace (Columbia University)
Metacognitive assessments of implicit memories
Metacognition has become a buzzword in the field of cognitive and educational psychology. For the most part, data revealing fairly good metacognitive abilities have come with assessments of what people know and don't know explicitly. For instance, how certain are you that you remember your own phone number? A question that has been largely ignored, however, is whether or not people have an ability to make accurate assessments of implicit memories. Using a non-verbal betting procedure in which participants risk a high or low number of points as a measure of certainty, children were trained on an implicit memory test. Results implicate that (i) metacognition might not be dependent on explicit knowledge, and (2) metacognition may consist of an automatic component.

P53 Kent D. Bodily (Georgia Southern University) & Jeffrey S. Katz, (Auburn University)
Like Honeybees, Humans Estimate Distance via Optical Flow
Optical flow is a visual self-motion cue which provides velocity and rotational information to the observer. Srinivisan, Zhang, & Bidwell (1997) manipulated optical flow (i.e., floor and wall patterns) of a tunnel in which honeybees searched for a goal. Bees searched accurately only under optical flow conditions, suggesting that bees estimate distance via optical flow. The present study adapted the tunnel task to test human participants in a desktop virtual environment. The floor and wall patterns varied between two optical flow conditions and a non-optical flow condition. Movement speed was manipulated to rule out timing. Distance estimates were highly accurate in optical flow conditions, but not in the absence of optical flow, irrespective of movement speed. Results suggest that, as for honeybees, optical flow alone is sufficient for distance estimation in humans.
P54 Fabian A. Soto & Edward A. Wasserman (University of Iowa)
Pigeons’ discrimination of identity and emotion in photographs of human faces
In two experiments, eight pigeons were trained with a go-no go discrimination involving black-and-white photographs of people displaying different facial emotions. The first experiment involved photographs of four people (two males and two females) showing the emotions of happiness, disgust, anger and surprise, whereas the second experiment involved a different group of people showing happiness, anger, sadness and fear. For each subject, responding to only one identity-emotion combination was reinforced, and generalization of responding was measured to all 16 possible combinations. All the pigeons readily learned the discrimination task, and the generalization results in both experiments consistently showed control of behavior by the two properties of the stimuli, with a tendency toward stronger control by identity than by emotion.
P55 Pamela J. Reid, Laura Davis & Kristen Collins (ASPCA Animal Behavior Center)
Do Dogs in Pairs Forage Efficiently?
The dog is a social species that, when living in a feral state, typically  scavenge together in refuse dumps and on village streets. Given the social nature of dogs and their reliance on competitive opportunistic feeding, we were curious to know if they are capable of understanding when they should join a partner in exploiting a food source and when they should forage elsewhere. We investigated the behavior of pairs of dogs foraging in a room where food was hidden. In the first setup, food was available in twop adjacent locations, only one of which could be monopolized at a time. In a second setup, we permitted one dog to watch its partner forage first before gaining access to the feeding apparatus. Dogs avoid close contact with their partners while they are feeding, but, once absent, they find their partners' empty foraging locations irresistible.
P56 Alejandra Rossi & Colin Allen (Indiana University)
Intentional behavior in dog-human communication
In this paper I investigate under what conditions showing behavior (transferring of information in an active way from the dog to the owner) emerges in dogs (N=10). In order to study this, the dogs were observed under different experimental conditions where the presence of the humans and/or hidden food was manipulated. We think that dogs will show the aforementioned behavior. We also analyzed the relation between the owner-dog relationship and the way the dog behaves in the communication task by analyzing video tapes of free playing time. We hypothesize that if the owner-dog relationship is more interactive, the dogs will tend to do more showing behavior than if the relation is less interactive. The results support our hypothesis.
P57 Wendi Fellner (The Seas, Epcot®, Walt Disney World® Resorts) and Heidi E. Harley (New College of Florida, The Seas, Epcot®, Walt Disney World® Resorts)
Bottlenose dolphin (Tursiops truncatus) whistles vary by context
The signature whistles of bottlenose dolphins can vary in frequency and duration parameters between contexts. However, how and why contextual differences affect the whistles is not clear. We analyzed whistles across time and contexts (e.g., perceptual assessment sessions, medical exams). A naïve sorter correctly categorized whistle spectrograms with 95.0% accuracy. Stereotyped whistles can change over time and context, and whistles with similar contours have the capacity to carry contextual information.
P58 Gin Morgan & Herbert S. Terrace (Columbia University)
Further Demonstrations of Metacognitive Skills in Rhesus Macaques (Macaca mulatta)
Recent experiments conducted in our lab (Kornell, Son, & Terrace, 2007) have shown that rhesus macaques can learn to make retrospective confidence judgments using "low" and "high" risk icons and transfer that skill to new perceptual tasks and a memory task.  We trained two rhesus macaques, both with experience making confidence judgments, on a new memory task, and both subjects showed immediate transfer of metacognitive skills when required to make retrospective confidence judgments.  Using the same memory task, subjects also learned to make prospective confidence judgments.  Last, results from a study involving the introduction of a third confidence level will be presented.
P59 Delgado, M., Wendel, L., & Cerutti, D. (University of California, East Bay)
Abstract.  We have recently initiated a programmatic study of the inter-session behavior of 10 laboratory pigeons serving in experiments on operant behavior.  Our first study involved filming the 12-hour “daytime” activity of caged birds.  Interval observations of various activities reveal that the individually housed pigeons are very active in their home cages, pacing, preening, pecking, and so forth, for a large portion of the day.  An unanticipated observation is that the pigeon’s behavior is inhibited when humans are present; we are now exploring the temporal distribution of their caged behavior in detail.  A second experiment now in progress examines their behavior in an aviary with various “enrichment” features such as cubbies and perches.  We anticipate that our findings will be relevant to concerns about appropriate housing for the laboratory pigeon.