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1.
During localization of a moving sound source, a shift of the perceived position relative to the actual one of the starting point is an expression of the perception of sluggishness of the auditory system. In this study, the human ability to localize starting points during a gradual or abrupt movement of fused auditory images (FAIs) was compared with the ability to localize the position of a stationary sound image. Sound images moved from the midline of the head in the direction of each of the ears. The subject’s responses were recorded using a graphics table. There was a tendency to shift the starting point of the trajectory in the direction of the movement. This tendency was stronger for gradual rather than for abrupt FAI movement and for shorter stimuli (100 ms) than for long ones (200 ms). The value of the starting point’s displacement depended on the final interaural time delay. The results obtained are discussed in terms of the “snapshots” and “movement detector” theories, as well as in terms of the sluggish and anticipatory ability of auditory perception.  相似文献   

2.
Although the traditional “lie detector” test is used frequently in forensic contexts, it has (like most test of deception) some limitations. The concealed knowledge test (CKT) focuses on participants’ recognition of privileged knowledge rather than lying per-se and has been studied extensively using a variety of measures. A “guilty” suspect’s interaction with and memory of crimescene items may vary. Furthermore, memory for crimescene items may diminish over time. The interaction of encoding quality and test delay on CKT efficiency has been previously implied, but not yet demonstrated. We used a response-time based CKT to detect concealed knowledge from shallow and deep study procedures after 10-min, 24-h, and 1-week delays. Results show that more elaborately encoded information afforded higher detection accuracy than poorly encoded items. Although classification accuracy following deep study was unaffected by delay, detection of poorly elaborated information was initially high, but compromised after 1 week. Thus, choosing optimal test items requires considering both test delay and initial encoding level.  相似文献   

3.
The “reverse migration hypothesis” as the explanation for the vagrancy of Far Eastern birds in Europe is commented on. It is concluded that, as the postulated switch of 180° along a great circle line would lead the eastern or even central Siberian birds to North America rather than to Europe, the application of the “reverse migration hypothesis” to them seems untenable (which, however, does not preclude its plausibility in case of transatlantic, southern European, or even southwestern Siberian vagrants). On the other hand, patterns of appearance of the Turdus [naumanni] superspecies (Machalska et al. 1967) suggest the relationship of the phenomenon of vagrancy to post-breeding nomadic movements and/or periodical invasions of non-migrating species.  相似文献   

4.
Animals emit visual signals that involve simultaneous, sequential movements of appendages that unfold with varying dynamics in time and space. Algorithms have been recently reported (e.g. Peters et al. in Anim Behav 64:131–146, 2002) that enable quantitative characterization of movements as optical flow patterns. For decades, acoustical signals have been rendered by techniques that decompose sound into amplitude, time, and spectral components. Using an optic-flow algorithm we examined visual courtship behaviours of jumping spiders and depict their complex visual signals as “speed waveform”, “speed surface”, and “speed waterfall” plots analogous to acoustic waveforms, spectrograms, and waterfall plots, respectively. In addition, these “speed profiles” are compatible with analytical techniques developed for auditory analysis. Using examples from the jumping spider Habronattus pugillis we show that we can statistically differentiate displays of different “sky island” populations supporting previous work on diversification. We also examined visual displays from the jumping spider Habronattus dossenus and show that distinct seismic components of vibratory displays are produced concurrently with statistically distinct motion signals. Given that dynamic visual signals are common, from insects to birds to mammals, we propose that optical-flow algorithms and the analyses described here will be useful for many researchers.Damian O. Elias and Bruce R. Land contributed equallyAn erratum to this article can be found at  相似文献   

5.
Jack Kerouac, the author of On The Road, was a central figure of the Beat Generation, a generation which rebelled against middle-class conformity in post–World War II America. Kerouac described himself as “a religious wanderer” (Kerouac 2006: 2), but an examination of his texts and life suggest his travels may also be understood as tourism. Viewed through the prism of tourism, this study will argue, for example, that MacCannell’s notion of the tourist’s quest for reality and authenticity (MacCannell 1989: 3) provides some insight into why Kerouac wrote that just south of Macon, Georgia, he and his travelling companion Neal Cassady stopped and got out of the car, “and suddenly both of us were stoned with joy to realize that in the darkness all around us was fragrant green grass and the smell of fresh manure and warm waters” (Kerouac 1957: 115). As Kerouac rebelled against being, as one of his protagonists in The Dharma Bums put it, “imprisoned in a system of work, produce, consume, work, produce, consume” (Kerouac 2006: 73) he travelled across America on a rapidly improving network of highways, turning “mobility into a retreat” (Holladay and Holton 2009: 42). Kerouac alternately identified himself as a hobo (Kerouac 1973: 181) and “not a real hobo” (Kerouac 1973: 173), but this article asks whether Kerouac’s travels were those of the last in a line of wanderers rebelling against conformity and modernization or a precursor of mobile mass tourism in America.  相似文献   

6.
Many populations live and disperse in advective media. A fundamental question, known as the “drift paradox” in stream ecology, is how a closed population can survive when it is constantly being transported downstream by the flow. Recent population-level models have focused on the role of diffusive movement in balancing the effects of advection, predicting critical conditions for persistence. Here, we formulate an individual-based stochastic analog of the model described in (Lutscher et al., SIAM Rev. 47(4):749–772, 2005) to quantify the effects of demographic stochasticity on persistence. Population dynamics are modeled as a logistic growth process and dispersal as a position-jump process on a finite domain divided into patches. When there is no correlation in the interpatch movement of residents, stochasticity simply smooths the persistence-extinction boundary. However, when individuals disperse in “packets” from one patch to another and the flow field is memoryless on the timescale of packet transport, the probability of persistence is greatly enhanced. The latter transport mechanism may be characteristic of larval dispersal in the coastal ocean or wind-dispersed seed pods.  相似文献   

7.
Giambattista Brocchi’s (1814) monograph (see Dominici, Evo Edu Outreach, this issue, 2010) on the Tertiary fossils of the Subappenines in Italy—and their relation to the living molluscan fauna—contains a theoretical, transmutational perspective (“Brocchian transmutation”). Unlike Lamarck (1809), Brocchi saw species as discrete and fundamentally stable entities. Explicitly analogizing the births and deaths of species with those of individual organisms (“Brocchi’s analogy”), Brocchi proposed that species have inherent longevities, eventually dying of old age unless driven to extinction by external forces. As for individuals, births and deaths of species are understood to have natural causes; sequences of births and deaths of species produce genealogical lineages of descent, and faunas become increasingly modernized through time. Brocchi calculated that over 50% of his fossil species are still alive in the modern fauna. Brocchi’s work was reviewed by Horner (1816) in Edinburgh. Brocchi’s influence as a transmutational thinker is clear in Jameson’s (1827) “geological illustrations” in his fifth edition of his translation of Cuvier’s Theory of the Earth (read by his student Charles Darwin) and in the anonymous essays of 1826 and 1827 published in the Edinburgh New Philosophical Journal—which also carried a notice of Brocchi’s death in 1827. The notion that new species replace older, extinct ones—in what today would be called an explicitly phylogenetic context—permeates these essays. Herschel’s (1830) discussion of temporal replacement of species and the modernization of faunas closely mirrors these prior discussions. His book, dedicated to the search for natural causes of natural phenomena, was read by Charles Darwin while a student at Cambridge. Darwin’s work on HMS Beagle was in large measure an exploration of replacement patterns of “allied forms” of endemic species in time and in space. His earliest discussions of transmutation, in his essay February 1835, as well as the Red Notebook and the early pages of Notebook B (the latter two written in 1837 back in England), contain Brocchi’s analogy, including the idea of inherent species longevities. Darwin’s first theory of the origin of species was explicitly saltational, invoking geographic isolation as the main cause of the abrupt appearance of new species. We conclude that Darwin was testing the predicted patterns of both Brocchian and Lamarckian transmutation as early as 1832 at the outset of his work on the Beagle.  相似文献   

8.
In their classic study of differences in mating strategies, Clark and Hatfield (1989, Journal of Psychology and Human Sexuality, 2, 39–54) found that men and women demonstrated a striking difference in interest in casual sex. The current study examined the role of an imagined requestor’s physical attractiveness (slightly unattractive, moderately attractive, and exceptionally attractive) on men’s and women’s willingness to accept three different requests (go out, come to apartment, go to bed) as reflected in answers to a questionnaire. We tested two hypotheses with a sample of 427 men and 443 women from three countries. Hypothesis 1 states that men, relative to women, will demonstrate a greater willingness to accept the “come to apartment” and “go to bed” requests but not the “go out” request for all three levels of requestor attractiveness. This hypothesis reflects Clark and Hatfield’s main findings. Hypothesis 2 states that the physical attractiveness of a potential partner will have a greater effect on women’s than on men’s willingness to accept all three requests, and particularly for the explicit request for casual sex. The results partially supported Hypothesis 1 and fully supported Hypothesis 2. The discussion highlights limitations of the current research and presents directions for future research.  相似文献   

9.
Theories of short term memory often include a limited capacity “buffer”. Such a buffer contains items which do not decay at all but are overwritten by new data. I show that one of the experiments that fueled the buffer concept, the free recall experiments by Murdock (J Exp Psychol 64(5):482–488, 1962), does not contain such a buffer.  相似文献   

10.
Almost any modern reader’s first encounter with Darwin’s writing is likely to be the “Historical Sketch,” inserted by Darwin as a preface to an early edition of the Origin of Species, and having since then appeared as the preface to every edition after the second English edition. The Sketch was intended by him to serve as a short “history of opinion” on the species question before he presented his own theory in the Origin proper. But the provenance of the “Historical Sketch” is somewhat obscure. Some things are known about its production, such as when it first appeared and what changes were made to it between its first appearance in 1860 and its final form, for the fourth English edition, in 1866. But how it evolved in Darwin’s mind, why he wrote it at all, and what he thought he was accomplishing by prefacing it to the Origin remain questions that have not been carefully addressed in the scholarly literature on Darwin. I attempt to show that Darwin’s various statements about the “Historical Sketch,” made primarily to several of his correspondents between 1856 and 1860, are somewhat in conflict with one another, thus making problematic a satisfactory interpretation of how, when, and why the Sketch came to be. I also suggest some probable resolutions to the several difficulties. How Darwin came to settle on the title “Historical Sketch” for the Preface to the Origin is not certain, but a guess may be ventured. When he first submitted the text to Asa Gray in February 1860 he called it simply “Preface Contributed by the Author to this American Edition” (Burkhardt et al., eds., vol. 8, 1993, p. 572; the collected correspondence is hereafter cited as CCD). In fact he had thought of it as being properly called a Preface much earlier, perhaps as early as 1856, as will be seen in what follows. It came to be called “An Historical Sketch of the Recent Progress of Opinion on the Origin of Species” only in the third English edition, April 1861. This is the title it retained thereafter, with the exception of an addition to the title in the sixth English edition, “Previously to the Publication of the First Edition of this Work” (Peckham, 1959, pp. 20, 59). The word “sketch,” on the other hand was one of two words Darwin commonly used in private correspondence to refer to the book that would later become the Origin, the other word being “Abstract,” and both signifying that Darwin thought of the work as being a resume rather than a full-fledged study (e.g., letter to J.D. Hooker, May 9 1856, CCD vol. 6 p. 106; letter to Baden Powell January 18 1860, CCD vol. 8 p. 41; letter to Lyell 25 June 1858, CCD v. 7, 1991, pp. 117–8; letter to Lyell May 1856, CCD, v. 6 p. 100). The most likely source of the title “Historical Sketch” for Darwin’s Preface is Charles Lyell’s Principles of Geology in which, beginning with the third edition (1834), Lyell added titles to his chapters, calling chapters 2–4 “Historical Sketch of the Progress of Geology” (Secord, in Lyell [1997], p. xlvii; for other uses by Lyell of this expression, cf. Porter, 1976, p. 95; idem 1982, p. 38; and Lyell, 1830 [1990], p. 30). Further parallels between Lyell’s Introduction and Darwin’s “Historical Sketch” in terms of content and strategy are suggested below.  相似文献   

11.
Four Bengalese finches were trained to discriminate 2 conspecific individuals in an operant chamber. Still visual images and contact calls were simultaneously presented to the subjects and specific (“correct”) perching response was reinforced with food. After the birds acquired the discrimination, they received the first test in which visual cues alone, auditory cues alone and combination of the 2 modalities were presented. Visual cues dominantly controlled the discriminative behavior of all birds. Then the subjects received the second test in which mixtures of the visual image of 2 stimulus birds appeared under 3 different auditory conditions, namely, no call, calls of 1 bird and calls of the other bird. Two subjects used the auditory cues when the visual stimulus was a mixture of 2 stimulus birds. These results suggest that the birds used less dominant cues when the dominant cues gave ambiguous information.  相似文献   

12.
Many songbirds develop remarkably large vocal repertoires, and this has prompted questions about how birds are able to successfully learn and use the often enormous amounts of information encoded in their various signal patterns. We have studied these questions in nightingales (Luscinia megarhynchos), a species that performs more than 200 different types of songs (strophen), or more than 1000 phonetically different elements composing the songs. In particular, we investigated whether and how both song repertoires and song performance rules of nightingales were coded by auditory stimuli presented in serial learning experiments. Evaluation of singing episodes produced by our trained birds revealed that nightingales cope well with an exposure to even long strings of master song-types. They can readily acquire information encoded within and between the different master songs, and they memorize, for example, which master song-types they have experienced in the same learning context. Imitations of such song-types form distinct sequential associations that are termed “context groups”. Additionally, nightingales develop other song-type associations that are smaller in size and termed “package groups”. Package formation results from constraints of the acquisition mechanisms which obviously lead to a segmentation of auditorily perceived master song sequences. Further experimentation validated that the song memory of nightingales is organized in a hierarchical manner and holding information about “context groups” composed of packages, “package groups” composed of songs, and songs composed of song elements. The evidence suggests that implementation of such a hierarchical organization facilitates a quick retrieval of particular songs, and thereby provides an essential prerequisite for a functionally appropriate use of large vocal repertoire is in songbirds. Received: 4 October 1997 / Accepted in revised form: 26 August 1998  相似文献   

13.
This paper demonstrates the importance of the reception and development of Goethe’s metamorphosis of plants as a methodological and philosophical framework in the history of botanical theories. It proposes a focus on the textbooks written by the German botanist Ludwig Reichenbach and his first attempt to use Goethe’s idea of metamorphosis of plants as fundamental to his natural system of plants published under the title ‘Botany for Women’, in German Botanik für Damen (1828). In this book, Reichenbach paid particular attention to Goethe’s sensitive views on the essence of nature; he regarded Goethe’s idea of metamorphosis in the plant kingdom as an ideal model to interpret connections of natural phenomena, in particular as a conceptual frame for a natural system. Furthermore, he aimed to develop the philosophical statement of the metamorphosis, in which he called for nature-philosophical conceptions in order to materialize his representation of plant “affinities,” and of a kind of “ontogeny” of the whole plant kingdom. This paper demonstrates that, between speculative views and empirical attempts, the extent to which Reichenbach actually belonged to a new “school” of thought, which left its mark on the history and philosophy of botany.  相似文献   

14.
We examined correlation between the development of slow potentials in the rhinal cortical region of cats and results of behavioral testing of visual recognition memory of these animals in the “delayed nonmatching-to-sample” (DNMS) selection version. Among different types of cognitive memory, the recognition memory occupies a special position because the process of taking off (retrieval) of a memory trace from the “stores” can be completely and effectively controlled by the experimenter (this process is initiated only after repetitive presentation of a stimulus identical to that whose trace should be subjected to retrieval or after presentation of an absolutely new stimulus whose trace had not been formed earlier). Recording of the field potentials was performed from the surface of the rhinal cortex using stereotaxically implanted mono- or bipolar Ag-AgCl electrodes after the experimental animals reached a sufficiently high level of successful performance of the test for recognition memory. Analysis of relations between negative slow potentials in the rhinal cortex and the correctness of performance (according to Spearman’s nonparametric test) demonstrated the existence of significant correlation between the electrophysiological and behavioral indices of visual recognition memory only within a late portion (final 10 sec but not initial 10 ones) of the retention interval for memorizing the trace of single presentation of a visual stimulus. The data obtained are interpreted as a confirmation of the existence of correlation between generation of negative slow potentials in the rhinal cortical region and the process of retrieval of the sample from the visual memory stores.  相似文献   

15.
Shoot apical meristem (SAM) domes derived from five different outdoor and in vitro sources of juvenile and mature Eucalyptus urophylla × Eucalyptus grandis akin genotypes were compared. Overall measurements of SAM dome height H and diameter D ranged from 2 to 35 μm and 20 to 80 μm, with significant differences according to the various physiological origins of plant material investigated. SAM domes from the mature trees “Mat” were taller than those from the rejuvenated ministock plants “Rej”; from the in vitro microcuttings “IVM” of the same clone and also from the in vitro juvenile seedlings “IVJ”, whereas outdoor seedlings “Juv” exhibited intermediate SAM dome height. SAM domes from the rejuvenated material “Rej”, from the in vitro mature “IVM” and juvenile “IVJ” origins were also narrower than those from the outdoor seedlings “Juv” and to lesser extent than those from the mature trees “Mat”. Overall, the mature source “Mat” displayed bigger and somehow sharper hemispherical domes than those from “Rej” and “Juv”, physiologically more juvenile, or those from the in vitro origins “IVM” and “IVJ” which looked flatter and smaller. SAM dome height, diameter D and H/D values varied also significantly according to the plastochron. More specifically, H, D, and H/D SAM differences between the five origins were not significant during the early plastochron phase corresponding to leaf initiation, to become more salient as leaf structures started to elongate and to differentiate. This was particularly obvious for mature tree “Mat” SAM dome shapes which showed at this stage much higher H/D values than the other SAM sources. A shape index S used for characterizing more accurately dome shape confirmed these trends. These observations provide additional arguments to the view that juvenility in trees becomes more and more time- and shoot-tip restricted as ageing increases in the course of time during the ontogenetical process and could be ultimately confined to the most organogenic phase of SAM, from which shoot characteristics derive.  相似文献   

16.
This paper utilizes Iris Marion Young’s critical, post-9/11 reading of Thomas Hobbes, “as a theorist of authoritarian government grounded in fear of threat” (Young 2003). Applying Young’s reading of Hobbes to the high-profile ethicist Julian Savulescu’s advocacy of genetic enhancement reveals an underlying unjust discrimination in Savulescu’s use of patriarchal protector–protected analogies between family and state. First, the paper shows how Savulescu’s concept of procreative beneficence, in which parents use genetic selection to have children who will have the “best lives” possible, is unjustly discriminatory against marginalized groups. Increasingly, however, he has invoked public security to justify genetic interventions. In recent speeches, Savulescu has argued a global state of emergency is developing due to a combination of the global environmental crisis, the threat of bioterrorism, and the failure of liberalism. To help deal with this emerging state of emergency, Savulescu advocates an unjustly discriminatory array of genetic-based governance practices, including detention and segregation.  相似文献   

17.
To clarify how the information of spatiotemporal sequence of the hippocampal CA3 affects the postsynaptic membrane potentials of single pyramidal cells in the hippocampal CA1, the spatio-temporal stimuli was delivered to Schaffer collaterals of the CA3 through a pair of electrodes and the post-synaptic membrane potentials were recorded using the patch-clamp recording method. The input–output relations were sequentially analyzed by applying two measures; “spatial clustering” and its “self-similarity” index. The membrane potentials were hierarchically clustered in a self-similar manner to the input sequences. The property was significantly observed at two and three time-history steps. In addition, the properties were maintained under two different stimulus conditions, weak and strong current stimulation. The experimental results are discussed in relation to theoretical results of Cantor coding, reported by Tsuda (Behav Brain Sci 24(5):793–847, 2001) and Tsuda and Kuroda (Jpn J Indust Appl Math 18:249–258, 2001; Cortical dynamics, pp 129–139, Springer-Verlag, 2004).  相似文献   

18.
Detailed analysis of Darwin’s scientific notes and other writings from the Beagle voyage reveals a focus on endemism and replacement of allied taxa in time and in space that began early in the journey. Though it is impossible to determine exactly when Darwin became a transmutationist, the evidence suggests that he was conversant with the transmutational ideas of Lamarck and others and testing (“experimenting” with) them—before he received a copy of Lyell’s Principles of Geology, vol. 2, in November 1832, in which Lyell describes and disputes Lamarck’s theory. To the two rhea species of Patagonia and the four mockingbird species of the Galapagos, we can now add the living Patagonian cavy (rodent) species, and its extinct putatively related species that Darwin collected at Monte Hermoso (Bahia Blanca) in the Fall of 1832, as a replacement pattern absolutely critical to the development of Darwin’s transmutational thinking. Darwin developed his first transmutational theory by adopting “Brocchi’s analogy” (Rudwick 2008)—i.e. that births and deaths of species are analogous to the births and deaths of individuals. Births and deaths of species, as of individuals, are thus explicable in terms of natural causes. Darwin explored these themes and the replacement of the extinct cavy by the modern species explicitly in his February 1835 essay (Darwin 1835a).
Niles EldredgeEmail:
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19.
According to Charles Hauss, “[i]n the last few years, reconciliation has become one of the ‘hottest’ topics in the increasingly ‘hot’ field of conflict resolution” (2003, ?1). However, despite the apparent interest in this “hot” academic topic (which is becoming increasingly warm in Canada as our own Truth and Reconciliation Commission commences), reconciliation studies have been dominated by Truth-based approaches. The restrictions of these approaches, which emphasize objectivity and rationality, often elide the body and the primacy of emotions in the reparative process. This essay begins a conversation on the role of the body and emotion in the study of reconciliation by engaging the work being done in the social sciences with contemporary trends in critical theory and literature. I argue that by looking at the fundamental role the body plays on the “road to reconciliation” we can devise a more vital approach to conflict resolution and the various processes that make it up.  相似文献   

20.
Twelve Bengalese finches (Lonchura striata var. domestica) were trained to discriminate between a conspecific and a heterospecific song in a go/no-go operant task. Training the birds to go for the conspecifics song or to go for the heterospecific song required the same number of training sessions. Nine possible cognitive tactics could be used to solve this task, but probe tests revealed that the birds used only four. Six birds memorized only the “no-go” stimulus and responded to the rest of the stimuli (no-go memory), two birds classified songs according to the species category (open-ended categorization), one bird memorized both of the training stimuli but responded by chance to the probe stimuli (rote categorization), and two birds combined open-ended and rote categorization tactics (combined categorization). These tactics were related to the number of sessions needed to reach the species-discrimination criterion. Our results suggest that investigators should consider individual cognitive tactics and the pitfalls of go/no-go discrimination when interpreting the results of operant discrimination tasks.  相似文献   

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