Perceptual grouping and detection of trial-unique emergent structures by pigeons.

Detecting global patterns in the environment is essential to object perception and recognition. Consistent with this, pigeons have been shown to readily detect and locate geometrically arranged, structured targets embedded in randomized backgrounds. Here we show for the first time that pigeons can detect and localize trial-unique targets derived solely from global patterns resulting from periodicity, symmetry and their combination using randomly generated segments of black and white local elements. The results indicate pigeons can perceptually segment and detect a wide variety of emergent global structures and do so even when they are unique to each trial. The perceptual and cognitive mechanisms underlying this discrimination likely play important roles in the abilities of how pigeons, and likely other birds, detect and categorize the properties of natural objects at different spatial scales.

Mice (Mus musculus) do not perceive emergent gestalt.

We have previously demonstrated that chimpanzees, similar to humans, can discriminate the orientations of a diagonal line better when lines are presented in redundant contexts than alone. In the present study, we examined whether the same redundant context facilitated diagonal-orientation discrimination in mice. Mice were presented one of three simultaneous, diagonal-orientation discrimination tasks: (a) presented alone, (b) presented with the context that resulted in emergent configurations in chimpanzees and humans, and (c) presented with the context not resulting in emergent configurations in chimpanzees or humans. In contrast to the facilitative effect of congruent context in chimpanzees and humans, the identical context did not facilitate the discrimination of the diagonal orientation in mice. This finding suggests that mice, unlike chimpanzees and humans, do not perceive emergent Gestalt. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Proton Conductive BaZr0.8-x Cex Y0.2 O3-δ : Influence of NiO Sintering Additive on Crystal Structure, Hydration Behavior, and Conduction Properties.

Y-doped BaZrO3 , BaCeO3 and BaZr1-x Cex O3 show high proton conductivity at intermediate temperature and are promising electrolyte candidates in electrochemical devices. However, in most cases, the present cell fabrication process seems to be unavailable to avoid the addition of NiO, which is either added to improve the sinterability of these electrolyte or diffuses from the electrode substrate during co-sintering. In this work, a systematic investigation was performed to study the effect of NiO on BaZr0.8-x Cex Y0.2 O3-δ (BZCY20) covering the full Ce range from 0 to 0.8. The results revealed that regardless of the composition of BZCY20, both the dehydration temperature and proton concentration decreased by adding NiO, which further greatly decreased the ionic conductivity and the transport number. And it is found that the redox cycles in Ce-rich samples containing Ni makes the grain boundary conductivity worse and the electrolyte brittle. The conclusion is that NiO is detrimental to the performance of the electrochemical cells using these materials as the electrolyte, although compromise might be achieved in certain degree by tuning the Ce content. However, it should be noted that to further improve the cell performance, a new sintering additive or new processing for cell fabrication is essential.

The whole is equal to the sum of its parts: Pigeons (Columba livia) and crows (Corvus macrorhynchos) do not perceive emergent configurations.

We previously demonstrated that chimpanzees, like humans, showed better accuracy and faster response time in discriminating visual patterns when the patterns were presented in redundant and uninformative contexts than when they were presented alone. In the present study, we examined the effect of redundant context on pattern discrimination in pigeons (Columba livia) and large-billed crows (Corvus macrorhynchos) using the same task and stimuli as those used in our previous study on chimpanzees. Birds were trained to search for an odd target among homogenous distractors. Each stimulus was presented in one of three ways: (1) alone, (2) with identical context that resulted in emergent configuration to chimpanzees (congruent context), or (3) with identical context that did not result in emergent configuration to chimpanzees (incongruent context). In contrast to the facilitative effect of congruent contexts we previously reported in chimpanzees, the same contexts disrupted target localization performance in both pigeons and crows. These results imply that birds, unlike chimpanzees, do not perceive emergent configurations.

The asymmetry defect of hippocampal circuitry impairs working memory in ß2-microglobulin deficient mice.

Left-right (L-R) asymmetry is a fundamental feature of brain function, but the mechanisms underlying functional asymmetry remain largely unknown. We previously identified structural and functional asymmetries in the circuitry of the mouse hippocampus that result from the asymmetrical distribution of NMDA receptor GluR ε2 (NR2B) subunits. By examining the synaptic distribution of ε2 subunits, we found that ß2-microglobulin (ß2m)-deficient mice that are defective in the stable cell surface expression of major histocompatibility complex class I (MHCI) lack this circuit asymmetry. To investigate the effect of hippocampal asymmetry defect on brain function, we examined working memory of ß2m-deficient mice in a delayed nonmatching-to-position (DNMTP) task. Mice were trained to nosepoke either a left or right key of a sample, to retain the position of the key during a delay interval, and then to choose the key opposite from the sample. During training sessions in which no programmed delay interval was imposed, the ß2m-deficient mice acquired the task as fast as control mice, suggesting that the discrimination of left and right positions is not impaired by the total loss of hippocampal asymmetry. In contrast, the ß2m-deficient mice made fewer correct responses than control mice when variable delay was imposed, suggesting that the asymmetry of hippocampal circuitry plays an important role in working memory.

Pigeons (Columba livia) fail to connect dots in learning biological motion.

Biological motion point-light displays provide a powerful method for studying motion perception. Nonhuman animals are capable of discriminating point-light displays, but it remains unknown how they perceive biological motion in these displays. We trained two groups of pigeons to discriminate video stimuli using two different classification rules. The motion-congruent group was trained to discriminate full-detail and corresponding point-light displays of pigeons from full-detail and point-light displays of humans. The motion-incongruent group was trained to discriminate full-detail pigeons and point-light humans from the other displays. Both groups acquired the discrimination. When tested with novel displays, pigeons showed good transfer of learning. Transfer was poorest with the point-light displays in the motion-congruent group. The results indicate that the pigeons failed to make the connection between the full-detail displays and their point-light counterparts even when the common motion was available as a cue.

Visual search and attention in blue jays (Cyanocitta cristata): Associative cuing and sequential priming.

Visual search for complex natural targets requires focal attention, either cued by predictive stimulus associations or primed by a representation of the most recently detected target. Because both processes can focus visual attention, cuing and priming were compared in an operant search task to evaluate their relative impacts on performance and to determine the nature of their interaction in combined treatments. Blue jays were trained to search for pairs of alternative targets among distractors. Informative or ambiguous color cues were provided before each trial, and targets were presented either in homogeneous blocked sequences or in constrained random order. Initial task acquisition was facilitated by priming in general, but was significantly retarded when targets were both cued and primed, indicating that the two processes interfered with each other during training. At asymptote, attentional effects were manifested mainly in inhibition, increasing latency in miscued trials and decreasing accuracy on primed trials following an unexpected target switch. A combination of cuing and priming was found to interfere with performance in such unexpected trials, apparently a result of the limited capacity of working memory. Because the ecological factors that promote priming or cuing are rather disparate, it is not clear whether they ever simultaneously contribute to natural predatory search.

Independent or integrated processing of interaural time and level differences in human auditory cortex?

Sound localization in the horizontal plane is mainly determined by interaural time differences (ITD) and interaural level differences (ILD). Both cues result in an estimate of sound source location and in many real-life situations these two cues are roughly congruent. When stimulating listeners with headphones it is possible to counterbalance the two cues, so called ITD/ILD trading. This phenomenon speaks for integrated ITD/ILD processing at the behavioral level. However, it is unclear at what stages of the auditory processing stream ITD and ILD cues are integrated to provide a unified percept of sound lateralization. Therefore, we set out to test with human electroencephalography for integrated versus independent ITD/ILD processing at the level of preattentive cortical processing by measuring the mismatch negativity (MMN) to changes in sound lateralization. We presented a series of diotic standards (perceived at a midline position) that were interrupted by deviants that entailed either a change in a) ITD only, b) ILD only, c) congruent ITD and ILD, or d) counterbalanced ITD/ILD (ITD/ILD trading). The sound stimuli were either i) pure tones with a frequency of 500 Hz, or ii) amplitude modulated tones with a carrier frequency of 4000 Hz and a modulation frequency of 125 Hz. We observed significant MMN for the ITD/ILD traded deviants in case of the 500 Hz pure tones, and for the 4000 Hz amplitude-modulated tone. This speaks for independent processing of ITD and ILD at the level of the MMN within auditory cortex. However, the combined ITD/ILD cues elicited smaller MMN than the sum of the MMN induced in response to ITD and ILD cues presented in isolation for 500 Hz, but not 4000 Hz, suggesting independent processing for the higher frequency only. Thus, the two markers for independent processing - additivity and cue-conflict - resulted in contradicting conclusions with a dissociation between the lower (500 Hz) and higher frequency (4000 Hz) bands.

Visual distance cues modulate neuromagnetic auditory N1m responses.

OBJECTIVE: Auditory distance judgment relies on several acoustic cues and can be modulated by visual information. Sound intensity serves as one such cue as it decreases with increasing distance. In this magnetoencephalography (MEG) experiment, we tested whether N1m MEG responses, previously described to scale with sound intensity, are modulated by visual distance cues. METHODS: We recorded behavioral and MEG data from 15 healthy normal hearing participants. Noise bursts at different sound pressure levels were paired with synchronous visual cues at different distances. We hypothesized that noise paired with far visual cues will be represented louder and result in increased N1m amplitudes compared to a pairing with close visual cues. This might be based on a compensation of visually induced distance when processing loudness. RESULTS: Psychophysically, we observed no significant modulation of loudness judgments by visual cues. However, N1m MEG responses at about 100ms after stimulus onset were significantly stronger with distal compared to proximal visual cues in the left auditory cortex. CONCLUSIONS: Our results suggest an audio-visual interaction at an early stage in the left auditory cortex, possibly related to cue integration for auditory distance processing. SIGNIFICANCE: Sound distance processing could prove itself as a promising model system for the investigation of intra-modal and cross-modal integration principles.

Perception of emergent configurations in humans (Homo sapiens) and chimpanzees (Pan troglodytes).

We examined the perceptions of emergent configurations in humans and chimpanzees using a target-localization task. The stimulus display consisted of a target placed among multiple identical distractors. The target and distractors were presented either solely, within congruent contexts in which salient configurations emerge, or within incongruent contexts in which salient configurations do not emerge. We found that congruent contexts had similar facilitative effects on target localization by humans and chimpanzees, whereas similar disruptive effects emerged when the stimuli were presented within incongruent contexts. When display size was manipulated, targets under the congruent-context condition were localized in a parallel manner, but those under the no-context and incongruent-context conditions were localized in a serial manner by both species. These results suggest that both humans and chimpanzees perceive emergent configurations when targets and distractors are presented within certain congruent contexts and that they process such emergent configurations preattentively.

Large-billed crows (Corvus macrorhynchos) have retrospective but not prospective metamemory.

Evidence of metamemory, the ability to monitor one's own memory, has been obtained in some primates, but it appears to be weaker in other species. In this study, we examined whether crows flexibly modulate their behavior by monitoring the strength of memory trace in a delayed matching-to-sample task using two paradigms. First, crows performing a memory test were given an escape option to decline taking the test (prospective metamemory). Second, crows were given the escape option as a "not confident" report after completing the test (retrospective metamemory). Accurate memory performance yielded a reward with a higher probability, whereas inaccurate memory performance resulted in no such recompense. The escape option yielded a reward with a lower probability. In the prospective metamemory test, crows escaped the memory test more frequently with longer delay intervals than they did with shorter delay intervals but no more frequently in the sample-omission than the sample-present trials, indicating that the crows decided to take the test or decline it by using the delay interval as a cue. In contrast, in the retrospective metamemory test, the crows escaped the memory test more frequently when their memory-test response was incorrect than correct and more frequently in the sample-omission than the sample-present trials, indicating that the crows recognized confidence regarding their choice in the memory test and utilized the escape option to maximize reward probability. Although these results suggest that crows retrospectively monitor the strength of memory trace, their prospective metamemory ability has not yet been confirmed in the present paradigm.

Interpreting the effects of image manipulation on picture perception in pigeons (Columba livia) and humans (Homo sapiens).

The effects of picture manipulations on humans' and pigeons' performance were examined in a go/no-go discrimination of two perceptually similar categories, cat and dog faces. Four types of manipulation were used to modify the images. Mosaicization and scrambling were used to produce degraded versions of the training stimuli, while morphing and cell exchange were used to manipulate the relative contribution of positive and negative training stimuli to test stimuli. Mosaicization mainly removes information at high spatial frequencies, whereas scrambling removes information at low spatial frequencies to a greater degree. Morphing leads to complex transformations of the stimuli that are not concentrated at any particular spatial frequency band. Cell exchange preserves high spatial frequency details, but sometimes moves them into the "wrong" stimulus. The four manipulations also introduce high-frequency noise to differing degrees. Responses to test stimuli indicated that high and low spatial frequency information were both sufficient but not necessary to maintain discrimination performance in both species, but there were also species differences in relative sensitivity to higher and lower spatial frequency information.

Left-right asymmetry defect in the hippocampal circuitry impairs spatial learning and working memory in iv mice.

Although left-right (L-R) asymmetry is a fundamental feature of higher-order brain function, little is known about how asymmetry defects of the brain affect animal behavior. Previously, we identified structural and functional asymmetries in the circuitry of the mouse hippocampus resulting from the asymmetrical distribution of NMDA receptor GluR ε2 (NR2B) subunits. We further examined the ε2 asymmetry in the inversus viscerum (iv) mouse, which has randomized laterality of internal organs, and found that the iv mouse hippocampus exhibits right isomerism (bilateral right-sidedness) in the synaptic distribution of the ε2 subunit, irrespective of the laterality of visceral organs. To investigate the effects of hippocampal laterality defects on higher-order brain functions, we examined the capacity of reference and working memories of iv mice using a dry maze and a delayed nonmatching-to-position (DNMTP) task, respectively. The iv mice improved dry maze performance more slowly than control mice during acquisition, whereas the asymptotic level of performance was similar between the two groups. In the DNMTP task, the iv mice showed poorer accuracy than control mice as the retention interval became longer. These results suggest that the L-R asymmetry of hippocampal circuitry is critical for the acquisition of reference memory and the retention of working memory.

Frequency tuning and latency organization of responses in the inferior colliculus of Japanese house bat, Pipistrellus abramus.

Pipistrellus abramus emits quasi-constant frequency pulses during search, which extend the end frequency portion of the downward frequency-modulated sweep (terminal frequency; TF). If the narrowed frequency range is important for detecting a small frequency change caused by insect fluttering, the bats may need much finer frequency resolution at the TF. To test this hypothesis, the distribution of the best frequencies (BFs) in the inferior colliculus (IC) was electrophysiologically measured. The TF of the echolocation pulse was 41.44+/-2.62 kHz. The frequency range of 35-45 kHz was overrepresented in the IC (n=50/105; 48%), and a faint second peak was seen at 75-85 kHz (the second harmonic of the TF) in the BF distribution. The BF increased as a function of recording depth along the dorsoventral axis, except for the BFs of 35-45 and 75-85 kHz, which were found at a wide range of depths. The response latency ranged between 3.7 and 23.2 ms for the BFs of 35-45 kHz, and the maximum target range was estimated to be 3.3 m from the delay line observed in the IC. These electrophysiological measures suggest the importance of a target distance within approximately 3 m, which is consistent with behavioral measures during foraging in this species.

Delayed matching-to-position performance in C57BL/6N mice.

Delayed matching-to-sample is one of the most frequently employed behavioral tasks for assessing spatial working memory in animals. Although the advantages of the task have been widely acknowledged and it is used in the study of a variety of species, its application to mice has been rare. In the present study, we reported the efficacy of a delayed matching-to-position task in C57BL mice lever-pressing in an operant-conditioning chamber. Each trial started with the press of a back lever, followed by the presentation of either a left or right front lever. When the ratio requirement for presses to the front lever (sample) was met, a delay interval started. Delay interval continued until the mice made the first response after the elapse of the programmed delay interval. This was followed by the presentation of a choice of left or right front levers. The choice of the same front lever as the sample was reinforced, whereas the other was not. The proportion of correct choices showed a delay-dependent decrement. A higher ratio of response requirement to the sample resulted in increased accuracy, but the duration of the intertrial interval had no effect. Preceding trials also influenced response accuracy, indicating proactive interference. Overall, the results replicated the effects of parametric manipulations reported in other species, and thus, our findings validate the efficacy of the task for assessing spatial working memory in laboratory mice.

[Global and local processing in vision: perspectives from comparative cognition].

Primates and birds are visually dominant species. Recent comparative studies in visual perception address questions about the differences between humans and nonhuman primates, as well as primates and birds. This paper discusses the relative importance of global and local visual processing in primates and birds. Although most nonhuman animals, unlike humans, show a local advantage when processing hierarchical compounding stimuli, studies using other types of stimuli revealed that primate vision may process-global information prior to local information. In contrast, the importance of global processing for birds is restricted for ecologically important stimuli such as conspecific images. Both global and local precedence in vision are the result of animals'equally successful adaptations to their living environments, implying that global-oriented human vision is not the only best system.

Schedule discrimination in a mixed schedule: implications for models of the variable-ratio, variable-interval rate difference.

In Experiment 1, each of three humans knowledgeable about operant schedules used mouse clicks to respond to a "work key" presented on a monitor. On a random half of the presentations, work-key responses that completed a variable ratio (VR) 12 produced a tone. After five tones, the work key was replaced by two report keys. Pressing the right or left report key, respectively, added or subtracted yen50 from a counter and produced the work key. On the other half of the presentations, a variable interval (VI) associated with the work key was defined so its interreinforcer intervals approximated the time it took to complete the variable ratio. After five tone-producing completions of this schedule, the report keys were presented. Left or right report-key presses, respectively, added or subtracted yen50 from the counter. Subjects achieved high yen totals. In Experiment 2, the procedure was changed by requiring an interresponse time after completion of the variable interval that approximated the duration of the reinforced interresponse time on the variable ratio. Prior to beginning, subjects were shown how a sequence of response bouts and pauses could be used to predict schedule type. Subjects again achieved high levels of accuracy. These results show humans can discriminate ratio from interval schedules even when those schedules provide the same rate of reinforcement and reinforced interresponse times.

The logic of the stimulus.

This paper examines the contribution of stimulus processing to animal logics. In the classic functionalist S-O-R view of learning (and cognition), stimuli provide the raw material to which the organism applies its cognitive processes-its logic, which may be taxon-specific. Stimuli may contribute to the logic of the organism's response, and may do so in taxon-specific ways. Firstly, any non-trivial stimulus has an internal organization that may constrain or bias the way that the organism addresses it; since stimuli can only be defined relative to the organism's perceptual apparatus, and this apparatus is taxon-specific, such constraints or biases will often be taxon-specific. Secondly, the representation of a stimulus that the perceptual system builds, and the analysis it makes of this representation, may provide a model for the synthesis and analysis done at a more cognitive level. Such a model is plausible for evolutionary reasons: perceptual analysis was probably perfected before cognitive analysis in the evolutionary history of the vertebrates. Like stimulus-driven analysis, such perceptually modelled cognition may be taxon-specific because of the taxon-specificity of the perceptual apparatus. However, it may also be the case that different taxa are able to free themselves from the stimulus logic, and therefore apply a more abstract logic, to different extents. This thesis is defended with reference to two examples of cases where animals' cognitive logic seems to be isomorphic with perceptual logic, specifically in the case of pigeons' attention to global and local information in visual stimuli, and dogs' failure to comprehend means-end relationships in string-pulling tasks.

Effects of Byakko-ka-ninjin-to on salivary secretion and bladder function in rats.

Byakko-ka-ninjin-to (BN) is a Kampo medicine (traditional Japanese medicine) that is frequently used to treat xerostomia, which is also a side effect of anticholinergic agents such as oxybutynin and propiverine widely used for the treatment of patients with urinary incontinence or frequency. We investigated the effects of BN on salivation and bladder function in rats, in the presence and absence of oxybutynin. Treatment with BN alone resulted in a slight increase in salivary secretions. In contrast, pilocarpine, a known muscarinic agonist, produced a significant increase in salivary secretions that could be blocked by pretreatment with oxybutynin. A single oral dose of BN at 200mg/kg body weight just before oxybutynin treatment resulted in less inhibition by oxybutynin of pilocarpine-induced salivation. However, BN had no effect on the decreased amplitude of bladder contractions that result from oxybutynin administration. These results suggest that BN might be useful for the xerostomia induced by anticholinergic agents, without influencing their beneficial effect on micturition.

Avian detection and identification of perceptual organization in random noise.

Recent research has suggested that pigeons may have difficulty globally integrating visual information in hierarchically arranged stimuli. To isolate and understand the mechanisms responsible for processing emergent perceptual structure, three pigeons were tested in a two alternative choice task that required the global integration of organized local information. They were reinforced for localizing, on randomized distractor backgrounds of black and white square elements, different types of structured targets (e.g., stripes, squares, checkerboards) arranged from these same elements. These hierarchical stimuli were tested at four different levels of spatial granularity (i.e., different element sizes). Experiment 1 found rapid acquisition for the vertical and horizontal stripes or square targets and somewhat slower learning with the checkerboard pattern. Experiment 2 demonstrated successful transfer to a novel target types (alternating bars and "diagonal" stripes). In both experiments, displays with the greatest spatial granularity (smallest elements and most repetitive structure) monotonically supported the best discrimination. These results indicate pigeons can perceive and discriminate emergent visual structure under the right circumstances and suggest they do so with a generalized rule for detecting patterns of non-random perceptual structure.