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Burs K, Möcklinghoff L, Marques MI, Schuchmann KL. Spatial and Temporal Adaptations of Lowland Tapirs (Tapirus terrestris) to Environmental and Anthropogenic Impacts. Life (Basel) 2022; 13. [PMID: 36676015 DOI: 10.3390/life13010066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022]
Abstract
The Pantanal is one of the most conserved wetland ecosystems in Brazil and a hotspot for biodiversity. Over the last decades intensification of human activities has become a major threat to the stability of the unique landscape. To establish effective conservation actions, it is essential to understand how species respond to anthropogenic and environmental regional factors. Here, data from two multiannual camera trap studies, one in the northern Pantanal and one in the southern Pantanal, were used to investigate the effects of habitat characteristics, seasons, and human interactions on the spatial and temporal patterns of lowland tapirs (Tapirus terrestris). Between 2010 and 2017, camera traps were repeatedly placed in consistent grids covering protected areas and areas with cattle-ranching and tourism. Data were analyzed using generalized linear mixed models and circular statistics. Activity patterns were similar and predominantly nocturnal in both areas, but tapirs indicated avoidance toward settlements and cattle and indicated habitat preferences only in the northern study area with less anthropogenic activities. The present study suggests that both environmental and anthropogenic factors can affect the species' spatial and temporal behavior, but tapirs show varying responses across regions and gradients of disturbance. The results indicate that adapting avoidance strategies might be more likely and effective in areas with low human pressure and sufficient protected areas as alternatives.
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Du WG, Shine R, Ma L, Sun BJ. Adaptive responses of the embryos of birds and reptiles to spatial and temporal variations in nest temperatures. Proc Biol Sci 2019; 286:20192078. [PMID: 31744441 DOI: 10.1098/rspb.2019.2078] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Natural nests of egg-laying birds and reptiles exhibit substantial thermal variation, at a range of spatial and temporal scales. Rates and trajectories of embryonic development are highly sensitive to temperature, favouring an ability of embryos to respond adaptively (i.e. match their developmental biology to local thermal regimes). Spatially, thermal variation can be significant within a single nest (top to bottom), among adjacent nests (as a function of shading, nest depth etc.), across populations that inhabit areas with different weather conditions, and across species that differ in climates occupied and/or nest characteristics. Thermal regimes also vary temporally, in ways that generate differences among nests within a single population (e.g. due to seasonal timing of laying), among populations and across species. Anthropogenic activities (e.g. habitat clearing, climate change) add to this spatial and temporal diversity in thermal regimes. We review published literature on embryonic adaptations to spatio-temporal heterogeneity in nest temperatures. Although relatively few taxa have been studied in detail, and proximate mechanisms remain unclear, our review identifies many cases in which natural selection appears to have fine-tuned embryogenesis to match local thermal regimes. Developmental rates have been reported to differ between uppermost versus lower eggs within a single nest, between eggs laid early versus late in the season, and between populations from cooler versus warmer climates. We identify gaps in our understanding of thermal adaptations of early (embryonic) phases of the life history, and suggest fruitful opportunities for future research.
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Affiliation(s)
- Wei-Guo Du
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, People's Republic of China
| | - Richard Shine
- Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia
| | - Liang Ma
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Bao-Jun Sun
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
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Abstract
The rapid shift to high-grain (HG) diets in ruminants can affect the function of the rumen epithelium, but the dynamic changes in the composition of the epithelium-associated (epimural) bacterial community in sheep still needs further investigation. Twenty male lambs were randomly allocated to four groups (n = 5). Animals of the first group received hay diet and represented a control group (CON). Simultaneously, animals in the other three groups (HG groups) were rapidly shifted to an HG diet (60% concentrate)which continued for 7 (HG7), 14 (HG14) and 28 (HG28) days, correspondingly. Results showed that ruminal pH dramatically decreased due to the rapid shift to the HG diet (P <0.001), while, the concentrations of butyrate (P <0.001), lactate (P = 0.001), valerate (P = 0.008) and total volatile fatty acids (P = 0.001) increased. Diversity estimators showed a dramatic decrease after the shift without recovering as the HG feeding continued. The principal coordinates analysis showed that CON group clustered separately from all HG groups with the presence of significant difference only between HG7 and HG28 (P = 0.034). The non-parametric multivariate analysis (npmv R-package) deduced that the primary significant differences in phyla and phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt)-predicted Kyoto Encyclopedia of Genes and Genomes (KEGGs) was attributed mainly to the diet composition (P <0.001, P = 0.001) compared to its application period (P = 0.140, 0.545) which showed a significant effect only on the genus (P = 0.001) and the operational taxonomic units (OTUs) level (P = 0.011). The Kruskal-Wallis test deduced that six phyla showed a significant effect due to the shift in diet composition. At the genus level, HG feeding altered the abundance of 12 taxa, four of which showed a significant variation due to the duration of the HG diet application. Similarly, we found that 21 OTUs showed significant variations due to the duration of the HG diet application. Furthermore, the genes abundance predicted by PICRUSt revealed that the HG feeding significantly affected seven metabolic pathways identified in the KEGG. Particularly, the abundance of gene families associated with carbohydrates metabolism were significantly higher in HG feeding groups (P = 0.027). Collectively, these results revealed that the rapid transition to an HG diet causes dramatic alterations in ruminal fermentation and the composition and function of ruminal epithelium-associated microbiome in sheep, while, the duration of the HG diet application causes drastic alterations to the abundance of some species.
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Affiliation(s)
- H Seddik
- Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,Laboratory of Gastrointestinal Microbiology,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,Jiangsu Province,China
| | - L Xu
- Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,Laboratory of Gastrointestinal Microbiology,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,Jiangsu Province,China
| | - Y Wang
- Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,Laboratory of Gastrointestinal Microbiology,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,Jiangsu Province,China
| | - S Y Mao
- Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,Laboratory of Gastrointestinal Microbiology,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,Jiangsu Province,China
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Ohba K, Sinha RA, Singh BK, Iannucci LF, Zhou J, Kovalik JP, Liao XH, Refetoff S, Sng JCG, Leow MKS, Yen PM. Changes in Hepatic TRβ Protein Expression, Lipogenic Gene Expression, and Long-Chain Acylcarnitine Levels During Chronic Hyperthyroidism and Triiodothyronine Withdrawal in a Mouse Model. Thyroid 2017; 27:852-860. [PMID: 28457184 PMCID: PMC5467114 DOI: 10.1089/thy.2016.0456] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Thyroid hormone (TH) has important roles in regulating hepatic metabolism. It was previously reported that most hepatic genes activated by a single triiodothyronine (T3) injection became desensitized after multiple injections, and that approximately 10% of target genes did not return to basal expression levels after T3 withdrawal, despite normalization of serum TH and thyrotropin (TSH) levels. To determine the possible mechanism(s) for desensitization and incomplete recovery of hepatic target gene transcription and their effects on metabolism, mRNA and/or protein expression levels of key regulators of TH action were measured, as well as metabolomic changes after chronic T3 treatment and withdrawal. METHODS Adult male mice were treated with daily injections of T3 (20 μg/100 g body weight) for 14 days followed by the cessation of T3 for 10 days. Livers were harvested at 6 hours, 24 hours, and 14 days after the first T3 injection, and at 10 days after withdrawal, and then analyzed by quantitative reverse transcription polymerase chain reaction, Western blotting, and metabolomics. RESULTS Although TH receptor (TRα and TRβ) mRNAs decreased slightly after chronic T3 treatment, only TRβ protein decreased before returning to basal expression level after withdrawal. The expression of other regulators of TH action was unchanged. TRβ protein expression was also decreased in adult male monocarboxylate transporter-8 (Mct8)-knockout mice, an in vivo model of chronic intrahepatic hyperthyroidism. Previously, increased hepatic long-chain acylcarnitine levels were found after acute TH treatment. However, in this study, long-chain acylcarnitine levels were unchanged after chronic T3, and paradoxically increased after T3 withdrawal. Pathway analyses of the previous microarray results showed upregulation of lipogenic genes after acute T3 treatment and withdrawal. Phosphorylation of acetyl-CoA carboxylase also decreased after T3 withdrawal. CONCLUSIONS Decreased hepatic TRβ protein expression occurred after chronic T3 exposure in adult male wild-type and Mct8-knockout mice. Gene array pathway and metabolomics analyses showed abnormalities in hepatic lipogenic gene expression and acylcarnitine levels, respectively, after withdrawal, despite normalization of serum TSH and TH levels. These findings may help explain the variable clinical presentations of some patients during hyperthyroidism and recovery, since TRβ protein, target gene expression, and metabolic adaptive changes can occur in individual tissues without necessarily being reflected by circulating TH and TSH concentrations.
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Affiliation(s)
- Kenji Ohba
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Rohit Anthony Sinha
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Brijesh Kumar Singh
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Liliana Felicia Iannucci
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Jin Zhou
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Jean-Paul Kovalik
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
| | - Xiao-Hui Liao
- 2 Department of Medicine, The University of Chicago , Chicago, Illinois
| | - Samuel Refetoff
- 2 Department of Medicine, The University of Chicago , Chicago, Illinois
- 3 Department of Pediatrics and Committee on Genetics, The University of Chicago , Chicago, Illinois
| | - Judy Chia Ghee Sng
- 4 Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Melvin Khee-Shing Leow
- 5 Department of Endocrinology, Tan Tock Seng Hospital, Singapore, Singapore
- 6 Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Paul Michael Yen
- 1 Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School , Singapore, Singapore
- 7 Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, North Carolina
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Kiecker C, Graham A, Logan M. Differential Cellular Responses to Hedgehog Signalling in Vertebrates-What is the Role of Competence? J Dev Biol 2016; 4:jdb4040036. [PMID: 29615599 PMCID: PMC5831800 DOI: 10.3390/jdb4040036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 11/24/2016] [Accepted: 12/01/2016] [Indexed: 12/21/2022] Open
Abstract
A surprisingly small number of signalling pathways generate a plethora of cellular responses ranging from the acquisition of multiple cell fates to proliferation, differentiation, morphogenesis and cell death. These diverse responses may be due to the dose-dependent activities of signalling factors, or to intrinsic differences in the response of cells to a given signal—a phenomenon called differential cellular competence. In this review, we focus on temporal and spatial differences in competence for Hedgehog (HH) signalling, a signalling pathway that is reiteratively employed in embryos and adult organisms. We discuss the upstream signals and mechanisms that may establish differential competence for HHs in a range of different tissues. We argue that the changing competence for HH signalling provides a four-dimensional framework for the interpretation of the signal that is essential for the emergence of functional anatomy. A number of diseases—including several types of cancer—are caused by malfunctions of the HH pathway. A better understanding of what provides differential competence for this signal may reveal HH-related disease mechanisms and equip us with more specific tools to manipulate HH signalling in the clinic.
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Affiliation(s)
- Clemens Kiecker
- Department of Developmental Neurobiology, King's College London, Hodgkin Building, Guy's Hospital Campus, London SE1 1UL, UK.
| | - Anthony Graham
- Department of Developmental Neurobiology, King's College London, Hodgkin Building, Guy's Hospital Campus, London SE1 1UL, UK.
| | - Malcolm Logan
- Randall Division of Cell & Molecular Biophysics, King's College London, Hodgkin Building, Guy's Hospital Campus, London SE1 1UL, UK.
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Abstract
Strong divergent selection leading to local adaptation is often invoked to explain the staggering diversity of bacteria in microbial ecosystems. However, examples of specialization by bacterial clones to alternative niches in nature are rare. Here, we investigate the extent of local adaptation in natural isolates of pseudomonads and their relatives to their soil environments across both space and time. Though most isolates grew well in most environments, patchily distributed low-quality environments were found to drive specialization. In contrast to experimental evolution work on microbial adaptation, temporal adaptation was stronger than spatial adaptation among the isolates and environments we sampled. Time-shift analysis of fitness across two seasons of growth revealed an unexpectedly strong effect of preadaptation. This pattern of apparent future adaptation may be caused by unknown abiotic properties of these environments, phages, bacterial competitors or general mechanisms of ecological niche release, and warrants future study.
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Affiliation(s)
- Susanne A Kraemer
- Institute of Evolutionary Biology, University of Edinburgh, Ashworth Laboratories, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK
| | - Rees Kassen
- University of Ottawa, Ottawa, Ontario, Canada
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Abstract
Tapping or clapping to an auditory beat, an easy task for most individuals, reveals precise temporal synchronization with auditory patterns such as music, even in the presence of temporal fluctuations. Most models of beat-tracking rely on the theoretical concept of pulse: a perceived regular beat generated by an internal oscillation that forms the foundation of entrainment abilities. Although tapping to the beat is a natural sensorimotor activity for most individuals, not everyone can track an auditory beat. Recently, the case of Mathieu was documented (Phillips-Silver et al. 2011 Neuropsychologia49, 961–969. (doi:10.1016/j.neuropsychologia.2011.02.002)). Mathieu presented himself as having difficulty following a beat and exhibited synchronization failures. We examined beat-tracking in normal control participants, Mathieu, and a second beat-deaf individual, who tapped with an auditory metronome in which unpredictable perturbations were introduced to disrupt entrainment. Both beat-deaf cases exhibited failures in error correction in response to the perturbation task while exhibiting normal spontaneous motor tempi (in the absence of an auditory stimulus), supporting a deficit specific to perception–action coupling. A damped harmonic oscillator model was applied to the temporal adaptation responses; the model's parameters of relaxation time and endogenous frequency accounted for differences between the beat-deaf cases as well as the control group individuals.
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Affiliation(s)
- Caroline Palmer
- Department of Psychology, McGill University, Montreal, Quebec, Canada H3A 1B1 Center for Research on Brain, Language and Music, McGill University, Montreal, Quebec, Canada H3G 2A8
| | - Pascale Lidji
- Department of Psychology, McGill University, Montreal, Quebec, Canada H3A 1B1 Center for Research on Brain, Language and Music, McGill University, Montreal, Quebec, Canada H3G 2A8
| | - Isabelle Peretz
- Center for Research on Brain, Language and Music, McGill University, Montreal, Quebec, Canada H3G 2A8 Department of Psychology, University of Montreal, Montreal, Quebec, Canada H2V 2S9
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van der Steen MCM, Keller PE. The ADaptation and Anticipation Model (ADAM) of sensorimotor synchronization. Front Hum Neurosci 2013; 7:253. [PMID: 23772211 PMCID: PMC3677131 DOI: 10.3389/fnhum.2013.00253] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 05/21/2013] [Indexed: 11/23/2022] Open
Abstract
A constantly changing environment requires precise yet flexible timing of movements. Sensorimotor synchronization (SMS)—the temporal coordination of an action with events in a predictable external rhythm—is a fundamental human skill that contributes to optimal sensory-motor control in daily life. A large body of research related to SMS has focused on adaptive error correction mechanisms that support the synchronization of periodic movements (e.g., finger taps) with events in regular pacing sequences. The results of recent studies additionally highlight the importance of anticipatory mechanisms that support temporal prediction in the context of SMS with sequences that contain tempo changes. To investigate the role of adaptation and anticipatory mechanisms in SMS we introduce ADAM: an ADaptation and Anticipation Model. ADAM combines reactive error correction processes (adaptation) with predictive temporal extrapolation processes (anticipation) inspired by the computational neuroscience concept of internal models. The combination of simulations and experimental manipulations based on ADAM creates a novel and promising approach for exploring adaptation and anticipation in SMS. The current paper describes the conceptual basis and architecture of ADAM.
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Affiliation(s)
- M C Marieke van der Steen
- Max Planck Research Group "Music Cognition and Action", Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany
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Kambara H, Shin D, Kawase T, Yoshimura N, Akahane K, Sato M, Koike Y. The effect of temporal perception on weight perception. Front Psychol 2013; 4:40. [PMID: 23450805 PMCID: PMC3584255 DOI: 10.3389/fpsyg.2013.00040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 01/16/2013] [Indexed: 11/26/2022] Open
Abstract
A successful catch of a falling ball requires an accurate estimation of the timing for when the ball hits the hand. In a previous experiment in which participants performed ball-catching task in virtual reality environment, we accidentally found that the weight of a falling ball was perceived differently when the timing of ball load force to the hand was shifted from the timing expected from visual information. Although it is well known that spatial information of an object, such as size, can easily deceive our perception of its heaviness, the relationship between temporal information and perceived heaviness is still not clear. In this study, we investigated the effect of temporal factors on weight perception. We conducted ball-catching experiments in a virtual environment where the timing of load force exertion was shifted away from the visual contact timing (i.e., time when the ball hit the hand in the display). We found that the ball was perceived heavier when force was applied earlier than visual contact and lighter when force was applied after visual contact. We also conducted additional experiments in which participants were conditioned to one of two constant time offsets prior to testing weight perception. After performing ball-catching trials with 60 ms advanced or delayed load force exertion, participants’ subjective judgment on the simultaneity of visual contact and force exertion changed, reflecting a shift in perception of time offset. In addition, timing of catching motion initiation relative to visual contact changed, reflecting a shift in estimation of force timing. We also found that participants began to perceive the ball as lighter after conditioning to 60 ms advanced offset and heavier after the 60 ms delayed offset. These results suggest that perceived heaviness depends not on the actual time offset between force exertion and visual contact but on the subjectively perceived time offset between them and/or estimation error in force timing.
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Affiliation(s)
- Hiroyuki Kambara
- Precision and Intelligence Laboratory, Tokyo Institute of Technology Yokohama, Japan
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Tanaka H, Homma K, Imamizu H. Illusory Reversal of Causality between Touch and Vision has No Effect on Prism Adaptation Rate. Front Psychol 2012; 3:545. [PMID: 23248609 PMCID: PMC3518875 DOI: 10.3389/fpsyg.2012.00545] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 11/16/2012] [Indexed: 12/02/2022] Open
Abstract
Learning, according to Oxford Dictionary, is “to gain knowledge or skill by studying, from experience, from being taught, etc.” In order to learn from experience, the central nervous system has to decide what action leads to what consequence, and temporal perception plays a critical role in determining the causality between actions and consequences. In motor adaptation, causality between action and consequence is implicitly assumed so that a subject adapts to a new environment based on the consequence caused by her action. Adaptation to visual displacement induced by prisms is a prime example; the visual error signal associated with the motor output contributes to the recovery of accurate reaching, and a delayed feedback of visual error can decrease the adaptation rate. Subjective feeling of temporal order of action and consequence, however, can be modified or even reversed when her sense of simultaneity is manipulated with an artificially delayed feedback. Our previous study (Tanaka et al., 2011; Exp. Brain Res.) demonstrated that the rate of prism adaptation was unaffected when the subjective delay of visual feedback was shortened. This study asked whether subjects could adapt to prism adaptation and whether the rate of prism adaptation was affected when the subjective temporal order was illusory reversed. Adapting to additional 100 ms delay and its sudden removal caused a positive shift of point of simultaneity in a temporal order judgment experiment, indicating an illusory reversal of action and consequence. We found that, even in this case, the subjects were able to adapt to prism displacement with the learning rate that was statistically indistinguishable to that without temporal adaptation. This result provides further evidence to the dissociation between conscious temporal perception and motor adaptation.
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Affiliation(s)
- Hirokazu Tanaka
- School of Information Science, Japan Advanced Institute of Science and Technology Nomi, Ishikawa, Japan
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Abstract
Many natural signals, including environmental sounds, exhibit scale-invariant statistics: their structure is repeated at multiple scales. Such scale-invariance has been identified separately across spectral and temporal correlations of natural sounds (Clarke and Voss, 1975; Attias and Schreiner, 1997; Escabi et al., 2003; Singh and Theunissen, 2003). Yet the role of scale-invariance across overall spectro-temporal structure of the sound has not been explored directly in auditory perception. Here, we identify that the acoustic waveform from the recording of running water is a self-similar fractal, exhibiting scale-invariance not only within spectral channels, but also across the full spectral bandwidth. The auditory perception of the water sound did not change with its scale. We tested the role of scale-invariance in perception by using an artificial sound, which could be rendered scale-invariant. We generated a random chirp stimulus: an auditory signal controlled by two parameters, Q, controlling the relative, and r, controlling the absolute, temporal structure of the sound. Imposing scale-invariant statistics on the artificial sound was required for its perception as natural and water-like. Further, Q had to be restricted to a specific range for the sound to be perceived as natural. To detect self-similarity in the water sound, and identify Q, the auditory system needs to process the temporal dynamics of the waveform across spectral bands in terms of the number of cycles, rather than absolute timing. We propose a two-stage neural model implementing this computation. This computation may be carried out by circuits of neurons in the auditory cortex. The set of auditory stimuli developed in this study are particularly suitable for measurements of response properties of neurons in the auditory pathway, allowing for quantification of the effects of varying the statistics of the spectro-temporal statistical structure of the stimulus.
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Affiliation(s)
- Maria N Geffen
- Department of Otorhinolaryngology - Head and Neck Surgery, University of Pennsylvania School of Medicine Philadelphia, PA, USA
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