Two experiments are reported investigating the order in which global and local information of visual forms is processed. Subjects were presented with compound stimuli and were asked to identify the local level, always consisting of small letters. At the global level, the stimuli could be either large letters, consistent or ...

Vibrotactile patterns were presented to subjects' left index fingerpads using the array from the Optacon. A set of simple (one-line) patterns and a set of complex (two-line) patterns were constructed so that they were equally identifiable when presented individually. In Experiment 1, discrimination performance was lower for two-line patterns than ...

Both on- and off-axis four-beam interference patterns are analyzed using ray tracing. The cross gratinglike interference pattern is accompanied by an extra term which consists of two orthogonal two-beam interference patterns. When partially coherent light is used, the extra term generally degrades the contrast of the cross gratinglike pattern unless ...

The bony nasopharynx increases its capacity predominantly by means of vertical development. Analogous to the facial structures is an expression of some somatotopic features that give rise to a higher and more shallow pharyngeal dimension in the dolichocephalic growth pattern. The nasopharynx's ultimate patency, however, depends on the growth and ...

Forty college students received a classical differential conditioning procedure involving both positive and negative patterning, each of these being associated with a different pair of stimuli. In positive patterning, elemental stimuli, A and B, were presented without an unconditioned stimulus while their compound, AB, was paired with electric shock. In ...

Demonstrations are presented to show that the perception of structure in Marroquin patterns is disrupted if the dots comprising the pattern have opposite contrast polarity, and also if the dots comprising the pattern are separated in stereoscopic depth. It is also demonstrated that the perception of structure in a Marroquin ...

Visual channels are defined psychophysically; stimuli that interact share information in the same channel, and those that do not interact are processed in different channels. Channels are often investigated by means of adaptation to one stimulus, testing contrast threshold elevation with one (or more) others. Much recent work has tested ...

In three experiments, listeners' abilities to detect changes in randomly generated tonal sequences were determined for sequences or "patterns" ranging in total duration from 62.5 ms to 2 s. Experiment 1 utilized an adaptive-tracking procedure, with n, the number of pattern components, as the dependent variable, and included a variety ...

This study reports the results of treatment of adolescents with King Types 2, 3, and 4 idiopathic curves using Cotrel-Dubousset instrumentation. Imbalance was seen in Types 2 and 4 curves when distraction direction hook patterns crossing the thoracolumbar junction were employed. Imbalance was not seen when a modified hook pattern ...

Using transient entrainment, the effect of the paced cycle length on the conduction through the reentrant circuit was assessed in recurrent sustained ventricular tachycardia (VT). Fourteen patients were included in the present study and their VTs were paced at multiple cycle lengths while the criteria of entrainment were confirmed at ...

The coherence function and phase spectrum were used to study the relationships between the discharges of sets of two postganglionic or preganglionic sympathetic nerves in baroreceptor-denervated cats anesthetized with either 5,5-diallylbarbiturate-urethan or alpha-chloralose. Most of the power in sympathetic nerve discharge was contained between 2 and 6 Hz. The coherence ...

Rectosigmoid electric control activity and intraluminal pressure were measured in the fasting state and after a standard 3040-kJ meal in irritable bowel syndrome (IBS) patients (n = 41), diverticulosis patients (n = 15), and healthy controls (n = 13). Analysis of myoelectric and motor patterns was performed computer-based with home-made ...

It is commonly believed that in humans epidermal ridge patterns are in regression relative to nonhuman primates, and they play no role in adaptive processes. In contrast with this we have found relationships between anthropometric and dermatoglyphic measurements in a sample of 61 normal males. Anthropometric variables included limb, trunk, ...

"This paper focuses on four interrelated aspects of the spatial dimension of city development [in China]. Attention is paid initially to the basic geography of urbanization, before turning to an analysis of recent trends in the pattern of urbanization. Spatial biases throughout the present-day hierarchy are then investigated and, finally, ...

Sets of regularly repeating auditory stimuli elicit unique perceptions; listeners are able to identify specific temporal patterns. Some temporal patterns are unambiguous (only one pattern can be perceived), while others are ambiguous (numerous patterns can be detected). While the psychophysical properties of such percepts have been well studied, little is ...

Animals make many different movements as circumstances dictate. These movements often involve the coordination of several neural networks, the output of which can be changed by modulatory substances. Here we report that the neuropeptide red pigment concentrating hormone modulates the interactions between two rhythmic pattern-generating networks in the lobster stomatogastric ...

Two predictions arising from previous theoretical and empirical work which demonstrated that spontaneous changes of bimanual coordination patterns result from a loss of pattern stability (i.e., a nonequilibrium phase transition) were tested: (a) that the time it takes to intentionally switch from one pattern to another depends on the differential ...

Pigment color patterns of molluscs are studied from the viewpoint of autonomy. Brownian algebra developed by Spencer-Brown (1969) is extensively used for the expression of cellular-automaton rules. When asynchronous updating is introduced for the transition of cellular automata, various kinds of patterns such as traveling waves, kinks, oscillatory local patterns ...

Subjects can accurately discriminate small changes in the relative position of features within a pattern. Simple patterns (intersected line segments) can undergo magnification and a variety of transformations without significantly affecting the discrimination thresholds. Features to be localized and compared need not be similar. We suggest that such relative position ...

Pattern electroretinograms were recorded to checkerboard stimuli of various check size to both onset-offset pattern and pattern reversal under most similar conditions of contrast and luminance. With onset-offset pattern the amplitude of the p-q and q-r components of the onset response showed a peak for checks of about 20 min ...

Temporal order judgments (TOJs) were obtained for tactile stimuli presented to subjects' fingerpads. In one set of measurements, pairs of spatial patterns were presented successively to a single fingerpad (same-site condition), to two fingers on the same hand (ipsilateral condition), or to two fingers on opposite hands (bilateral condition). The ...

Experimental evidence suggests that altered muscular function can influence craniofacial morphology. The switch from a nasal to an oronasal breathing pattern induces functional adaptations that include an increase in total anterior face height and vertical development of the lower anterior face. While some animals studies have suggested predictable growth patterns ...

Upright locomotion has been, perhaps, the most studied of all human motor behaviors. The acquisition of this motor milestone has been of major interest to developmentalists from the motor as well as the cognitive domains. Until recently, developmentalists have chosen a nonexperimental approach, opting instead to describe the motor behaviors ...

The tactile recognition of an object held in the hand involves characterizing its surface features. Recent neurophysiological studies point to a number of possible ways in which tactile primary afferents convey information about surface characteristics. The spatial pattern of the afferents that are activated probably underlies the unique recognition of ...

Specific patterns of neurologic involvement within the 8 Functional Systems (Pyramidal, Cerebellar, Brain Stem, Sensory, Bowel & Bladder, Visual, Cerebral, Other) in a well-documented series of early MS patients have been presented in rank order of expected frequency. The first 35 and the first 86 of the 256 possible patterns ...

To enhance the efficiency of de visu or automatic detection and analysis of of the respiratory patterns, new techniques are introduced to process the respiratory signals. These techniques include: the dynamical frequency analysis, spectral envelope detection, three-dimensional representation of the spectral envelopes, and the 'respirogram'.

When presented a series of patterns inside a frame, subjects unintentionally retained information concerning the frame-relative location of the elements composing the patterns; they could use this superficial information to estimate the frequency with which the elements occurred at various locations within the frame. There were two aspects of the ...

This study shows how the identification of relevant collective variables for behavioral patterns and evaluation of their stability may lead to a better understanding of processes underlying pattern change in coordinated human motor behavior. Based upon observed transitions in behavioral patterns, relative phase was identified as an appropriate collective variable ...

We recorded visual evoked responses (VERs) to alternating, checkerboard pattern stimuli using the scanning laser ophthalmoscope (SLO). Retinal position and focus of checkerboard stimuli were monitored on the SLO video monitor throughout testing. Checkerboard size, check size, and retinal positions were varied. Consistent with other, well-established pattern reversal techniques, the ...

The signature vector method is target pattern rotationinvariant but does not discriminate well against many other patterns with a similar vector but different shapes.

Unit activity in the medial septal area of the rat was studied during pavlovian appetitive differential conditioning. The firing pattern of cells in the medial septum is that of suppression to presentation of the conditioned excitor and no significant increase to the presentation of the conditioned inhibitor. This pattern is ...

In previous studies, we showed that in the monkey, systemically administered N-methyl, 4-phenyl, 1-2-3-6 tetrahydropyridine (MPTP) produces a chronic parkinsonian syndrome accompanied by spatial frequency-dependent abnormalities in both the pattern electroretinogram and visual evoked potential. We describe the effect of intravitreally administered 6-hydroxydopamine (6-OH-DA) on the pattern electroretinogram and pattern ...

A new perimetric pattern discrimination test was compared with conventional automated perimetry (Humphrey program 30-2 or Octopus program 32) in glaucoma patients, glaucoma suspects, and control subjects. The new test is based on the rationale that a greater percentage of retinal ganglion cells should be needed to detect a stimulus ...

The observed transition frequencies of behaviour patterns were obtained for isolated lizards (Gallotia galloti), as well as those expected if the patterns were independent. The transitions differing significantly from random were calculated when: (1) the animals had an electrode in their lateral hypothalamic area (I); (2) they were electrically stimulated ...

The analysis of spatial structure, ie, the encoding of relative positions between pattern elements, was studied in central and eccentric vision. In a two-alternative forced-choice task the observer had to discriminate between two patterns consisting of short line segments. At each trial the two patterns were flashed for 140 msec ...

The aim of the present experiments was to investigate the maximum displacement over which coherent motion can be perceived (Dmax) for a stroboscopically illuminated moving random-dot pattern, both as a function of the size of the pattern and as a function of the spatial-frequency content. Perception of coherent motion was ...

We model a small system of hypothetical neurons having ongoing afferent input ("stimulus") short-term refraction/inhibition, and brief-latency intercellular excitatory feedback loops. We incorporate postsynaptic plasticity: synapses onto a given cell are grouped into dendritic "neighborhoods" wherein sufficiently large local postsynaptic potentials sums cause proportional changes in local synaptic efficacy. The ...

The pattern electroretinogram (PERG), thought to be generated in retinal ganglion cells, is a recent addition to the neurophysiologic assessment of retinal function. Factors that affect the PERG include type of pattern-reversal stimulus, spatial frequency of the pattern, luminance and contrast of the pattern, method of waveform processing, type of ...

Various experiments are surveyed in this paper that may throw light on how the degree of spatial organization of the Xenopus embryo increases during development. The events of the 100 minutes or so that follow fertilization may do little more than orientate and give proportions, within the egg's yolky vegetal ...

The basic body plan of insects is set up in response to determinants initially localized at the anterior and posterior poles of the egg. Early in development, these determinants give rise to a series of morphogen gradients which in turn trigger a cascade of molecular signals determining the body pattern. ...

Acoustical sequences were divided by time intervals of various durations, and the performance of finger tappings following the stimuli were recorded. The results proved that it is difficult to synchronize finger tapping with irregular acoustical patterns. The subjects tended to transform the irregular stimulus patterns into more regular response patterns ...

1. A particular firing pattern among simultaneously observed neurons represents a particular sequence of activity. If any multineuron pattern repeats significantly more than expected by chance, we may be observing a repeated state of a neural assembly as it processes similar units of information. 2. We present here an algorithm ...

Basic and clinical behavioral research reveals that actions of the organism frequently are organized to form concurrent and sequential response patterns. The former are nonrandom interrelationships among two or more responses that are measured over the same time period. Sequential response patterns are nonrandom relationships between responses when measured over ...

Those who attempt to characterize the functions of the cerebral hemispheres tend, broadly speaking, to do so either in terms of structural specializations or of different information-processing modes. Often little attention is paid to the possible importance, in determining the outcome of experiments in this field, of interhemispheric processes. An ...

The three papers presented by Noden, Thorogood and Lumsden in this session encompassed the connective tissues as broadly defined, i.e. soft (fibrous) connective tissue, cartilage, bone, muscle and the dental tissues, enamel and dentine, and utilized a variety of experimental techniques on both avian and mammalian embryos to explore specificity ...

There is some evidence from grating experiments that the transient presentation of a stimulus pattern interferes with the encoding of positional relationships between pattern elements (i.e. the analysis of spatial structure) more in eccentric vision than in central vision. The present study investigated the effect of exposure duration on the ...

Differences between central and eccentric vision in the detection of mirror symmetry were investigated using patterns consisting of small dots. In each trial, a dot pattern was flashed for 140 msec and the subject had to decide whether the upper and lower parts of the dot pattern contained mirror symmetric ...

Carollia perspicillata (Phyllostomidae) is a frugivorous bat that emits low-intensity, broadband, frequency-modulated echolocation pulses through nostrils surrounded by a noseleaf. The emission pattern of this bat is of interest because the ratio between the nostril spacing and the emitted wavelength varies during the pulse, causing complex interference patterns in the ...

We examined the determinants of 2-month-olds' preferences among facelike and abstract patterns. Observed preferences were compared with the predictions of two preference models--one based on stimulus energy (as measured by the amplitude spectrum) and the other based on stimulus structure (as measured by the phase spectrum). It is known that ...

Correlation patterns between the electroencephalographic activity of both hemispheres in adult subjects were obtained. The morphology of these patterns for one subject was compared with another subject's patterns during control situations without communication, and during sessions in which direct communication was stimulated. Neither verbalization nor visual or physical contact are ...