bluuebunny/crossref_metadata_2025 huggingface dataset:
Lmx1a and Lmx1b Function Cooperatively to Regulate Proliferation, Specification, and Differentiation of Midbrain Dopaminergic Progenitors
Authors: Yan Carol H. , Levesque Martin , Claxton Suzanne , Johnson Randy L. , Ang Siew-Lan
Published: September 2011

LIM homeodomain transcription factors, Lmx1a and Lmx1b, are required for the development of midbrain dopaminergic (mDA) neurons. Lmx1b is required for the specification and maintenance of mDA neurons, primarily due to its role in isthmic organizer development that is essential for the induction of mDA neurons. Here, we conditionally deleted Lmx1b in the ventral neural tube usingShhCreand found thatLmx1bconditional mutant mouse embryos show no defect in the development and maintenance of mDA neurons. In addition,Dreher(Lmx1a mutant) embryos display only a moderate reduction in the number of mDA neurons, suggesting that the related family member Lmx1b might compensate for Lmx1a function. We therefore generatedLmx1aandLmx1bdouble mutants. Severe loss of mDA neurons occurred inLmx1adr/dr;ShhCre/+;Lmx1bf/fdouble mutants due to essential roles for Lmx1a and Lmx1b in regulating the proliferation and neuronal commitment of mDA progenitors through the expression of Wnt1 and Ngn2, respectively. Lmx1a and Lmx1b also negatively regulateHes1expression and consequently cell cycle exit through activation of p27Kip1expression. In addition, Lmx1a and Lmx1b also regulate the expression of floor plate genes such asCorinandSlit2and specification of postmitotic mDA neurons. These defects were more severe with decreasing gene dosage of Lmx1a and Lmx1b or observed only when all four copies of Lmx1a and Lmx1b genes were inactivated. Together, our results demonstrate that Lmx1a and Lmx1b function cooperatively to regulate proliferation, specification, and differentiation of mDA progenitors, including their floor plate-like properties.
Frequency of Subthreshold Oscillations at Different Membrane Potential Voltages in Neurons at Different Anatomical Positions on the Dorsoventral Axis in the Rat Medial Entorhinal Cortex
Authors: Yoshida Motoharu , Giocomo Lisa M. , Boardman Ian , Hasselmo Michael E.
Published: September 2011

Neurons from layer II of the medial entorhinal cortex show subthreshold membrane potential oscillations (SMPOs) which could contribute to theta-rhythm generation in the entorhinal cortex and to generation of grid cell firing patterns. However, it is unclear whether single neurons have a fixed unique oscillation frequency or whether their frequency varies depending on the mean membrane potential in a cell. We therefore examined the frequency of SMPOs at different membrane potentials in layer II stellate-like cells of the rat medial entorhinal cortexin vitro. Using whole-cell patch recordings, we found that the fluctuations in membrane potential show a broad band of low power frequencies near resting potential that transition to more narrowband oscillation frequencies with depolarization. The transition from broadband to narrowband frequencies depends on the location of the neuron along the dorsoventral axis in the entorhinal cortex, with dorsal neurons transitioning to higher-frequency oscillations relative to ventral neurons transitioning to lower-frequency oscillations. Once SMPOs showed a narrowband frequency, systematic frequency changes were not observed with further depolarization. Using a Hodgkin–Huxley-style model of membrane currents, we show that differences in the influence of depolarization on the frequency of SMPOs at different dorsal to ventral positions could arise from differences in the properties of the h current. The properties of frequency changes in this data are important for evaluating models of the generation of grid cell firing fields with different spacings along the dorsal-to-ventral axis of medial entorhinal cortex.
Dopamine-Dependent Long-Term Depression Is Expressed in Striatal Spiny Neurons of Both Direct and Indirect Pathways: Implications for Parkinson's Disease
Authors: Bagetta Vincenza , Picconi Barbara , Marinucci Silvia , Sgobio Carmelo , Pendolino Valentina , Ghiglieri Veronica , Fusco Francesca R. , Giampà Carmen , Calabresi Paolo
Published: September 2011

Striatal medium spiny neurons (MSNs) are divided into two subpopulations exerting distinct effects on motor behavior. Transgenic mice carrying bacterial artificial chromosome (BAC) able to confer cell type-specific expression of enhanced green fluorescent protein (eGFP) for dopamine (DA) receptors have been developed to characterize differences between these subpopulations. Analysis of these mice, in contrast with original pioneering studies, showed that striatal long-term depression (LTD) was expressed in indirect but not in the direct pathway MSNs. To address this mismatch, we applied a new approach using combined BAC technology and receptor immunohistochemistry. We demonstrate that, in physiological conditions, DA-dependent LTD is expressed in both pathways showing that the lack of synaptic plasticity found in D1eGFP mice is associated to behavioral deficits. Our findings suggest caution in the use of this tool and indicate that the “striatal segregation” hypothesis might not explain all synaptic dysfunctions in Parkinson's disease.
Amino Acids for the Neonate: Search for the Ideal Dietary Composition
Authors: Vlaardingerbroek H. , van den Akker C.H.P. , de Groof F. , Hogewind-Schoonenboom J.E. , Huang L. , Riedijk M.A. , van der Schoor S.R.D. , Huang Y. , van Goudoever J.B.
Published: September 2011

Amino acids play crucial roles as precursors for proteins and neurotransmitters, as transport molecules, and in cell signaling. In this review, we describe the unique functions of the individual amino acids and conclude that the amino acid requirements of parenterally fed neonates are inadequately defined. Parenterally fed neonates are at risk of amino acid deficiency or toxicity because the intestines serve as an important site of metabolism, regulating systemic availability of individual amino acids.
Tissues Involved in Sex Pheromone Production in Phyllophaga obsoleta (Coleoptera: Scarabaeoidea: Melolonthidae)
Authors: Romero-López Angel A , Arzuffi René , Valdez Jorge , Sánchez-Espíndola Esther , Morón Miguel A
Published: September 2011

Females of Phyllophaga obsoleta (Blanchard) (Coleoptera: Scarabaeoidea: Melolonthidae) perform “sexual calling” with their protractile genital chamber (PGC) exposed to release substances that attract males. Histological aspects of the PGC and accessory glands (AGs) of P. obsoleta females were studied. Studies with light microscope and transmission electron microscope revealed exocrine tissue in the posterior section of the PGC, where it might be producing the attractants. This epithelial gland is formed by a basement membrane, a hypodermis for substance production, secretion, and transport (cells, nucleus, mitochondria, endoplasmic reticulum, Golgi complex, and presence of folds in the plasma membrane), as well as evidence of the substance to be secreted to the outside (connecting cuticular pores to plasma membrane). Histological similarities between AG types I and II were observed, although only the PGC had properties of class I cells. These results suggest that the posterior section of the P. obsoleta PGC is involved in sex pheromone production.
Diptera-Specific Polymerase Chain Reaction Amplification Primers of use in Molecular Phylogenetic Research
Authors: Gibson Joel F , Kelso Scott , Jackson Morgan D , Kits Joel H , Miranda Gil F G , Skevington Jeffrey H
Published: September 2011

DNA sequence data from a variety of mitochondrial and nuclear gene regions are significant components of phylogenetic research in entomology. Polymerase chain reaction (PCR) amplification primers for many gene regions have been developed that are specific to a range of dipteran groups. Here, we review the existing Diptera-specific PCR amplification primers that have been published for 11 mitochondrial and nuclear gene regions: 12S small ribosomal subunit, cytochrome b, cytochrome oxidase c subunit I, 28S ribosomal RNA, alanyl-tRNA synthetase, the carbamoyl phosphate synthase region of CAD, elongation factor-1α, 6-phosphogluconate dehydrogenase, triose phosphate isomerase, white, and wingless. We also have designed in total 94 new PCR amplification primers for use in these same gene regions. Our new primers have been developed and tested using our DNA sequence database of > 1,600 specimens representing 40 families of Diptera. All of the past and newly developed primer sequences are presented in tables, and their locations are shown on gene maps. This combined data will facilitate future molecular phylogenetic research within Diptera.
Notes on Biology and Behavior of Rhinoceros BeetleEnema pan(Coleoptera: Scarabaeidae: Dynastinae)
Authors: Puker Anderson , Rodrigues Sérgio R , Tiago Elison F , Ide Sergio , Fuhrmann Juares
Published: September 2011

Dynastinae beetles (Coleoptera: Scarabaeidae) are important due to their role in recycling plant material and promoting nutrient turnover. However, some species are phytophagous and can attack crop plants, thus becoming pests. Here, we provide information on the biology and behavior of the rhinoceros beetle Enema pan (F.) (Oryctini), an abundant species in the area of Cerrado-Pantanal ecotone, Aquidauana, Mato Grosso do Sul, Brazil. Adults were collected with a light trap deployed daily from January 2006 to December 2007 in the experimental farm of the Universidade Estadual de Mato Grosso do Sul (Aquidauana campus). Adults were maintained in plastic containers and observations were made daily. Temporal distribution of adults of E. pan occurred in September and October (2006) and from October to December (2007). Flight started at 1930 hours and ended at 2330 hours. Twenty-four eggs (3.28 mm in length by 2.32 mm in width) with a whitish color were ovipositioned directly in to the soil. Adult longevity averaged 22.0 d in the laboratory conditions. Cephalic horn length, body length, and width of E. pan males are greater than those of females. The weight of adults of both sexes was similar. Cephalic horn length of the males of E. pan was positively correlated with his body size. Mating occurred between 0800 and 1030 hours and lasted on average 18.1 min in the laboratory. Several fights among males and other behaviors involving males and females were observed and are reported.
Redescription of Prorhinotermes japonicus (Isoptera: Rhinotermitidae) from Taiwan
Authors: Li Hou-Feng , Lan Yen-Chiu , Su Nan-Yao
Published: September 2011

The winged imago of Prorhinotermes japonicus (Holmgren 1912) is described herein for the first time. The soldier caste and two morphs of the neotenic caste also are redescribed. Based on the similar morphology of soldier, alate and neotenic, two Chinese species, Prorhinotermes xishaensisLi & Tsai 1976 and Prorhinotermes hainanensisPing & Xu 1989, are reverted to junior synonyms of P. japonicus. The current distribution of P. japonicus includes tropical islands surrounding the northern part of the South China Sea. Another Chinese species, Prorhinotermes spectabilisPing & Xu 1989 from Yunnan Province and two Philippines species, Prorhinotermes tibiaoensis (Oshima 1920) and Prorhinotermes gracilisLight 1921, were compared and included in discussion.
FIXED‐TIME SCHEDULE EFFECTS IN COMBINATION WITH RESPONSE‐DEPENDENT SCHEDULES
Authors: Borrero John C. , Bartels‐Meints Jamie A. , Sy Jolene R. , Francisco Monica T.
Published: September 2011

We evaluated the effects of fixed‐interval (FI), fixed‐time (FT), and conjoint (combined) FI FT reinforcement schedules on the responding of 3 adults who had been diagnosed with schizophrenia. Responding on vocational tasks decreased for 2 of 3 participants under FT alone relative to FI alone. Responding under FI FT resulted in response persistence for 2 of 3 participants. Results have implications for the maintenance of desirable behavior, as well as for situations in which FT treatment has been implemented for problem behavior and problem behavior is nevertheless reinforced by caregivers.
REINFORCEMENT OF VOCALIZATIONS THROUGH CONTINGENT VOCAL IMITATION
Authors: Pelaez Martha , Virues‐Ortega Javier , Gewirtz Jacob L.
Published: September 2011

Maternal vocal imitation of infant vocalizations is highly prevalent during face‐to‐face interactions of infants and their caregivers. Although maternal vocal imitation has been associated with later verbal development, its potentially reinforcing effect on infant vocalizations has not been explored experimentally. This study examined the reinforcing effect of maternal vocal imitation of infant vocalizations using a reversal probe BAB design. Eleven 3‐ to 8‐month‐old infants at high risk for developmental delays experienced contingent maternal vocal imitation during reinforcement conditions. Differential reinforcement of other behavior served as the control condition. The behavior of 10 infants showed evidence of a reinforcement effect. Results indicated that vocal imitations can serve to reinforce early infant vocalizations.
Effects of hyperbaric oxygen treatment on horses with experimentally induced endotoxemia
Authors: Baumwart Chad A. , Doherty Tom J. , Schumacher James , Willis Rebekah S. , Adair Henry S. , Rohrbach Barton W.
Published: September 2011

Objective—To determine the effectiveness of preinduction hyperbaric oxygen treatment (HBOT) in ameliorating signs of experimentally induced endotoxemia in horses.

Animals—18 healthy adult horses.

Procedures—Horses were randomly assigned to 1 of 3 equal-sized treatment groups to receive normobaric ambient air and lipopolysaccharide (LPS), HBOT and LPS, or HBOT and physiologic saline (0.9% NaCl) solution. Horses were physically examined, and blood was obtained for a CBC and to determine concentration or activity of plasma tissue necrosis factor-α, blood lactate, and blood glucose before the horses were treated with HBOT and then intermittently for 6 hours after administration of LPS or physiologic saline solution.

Results—All LPS-treated horses developed signs and biochemical and hematologic changes consistent with endotoxemia. Treatment with HBOT significantly ameliorated the effect of LPS on clinical endotoxemia score but did not significantly improve other abnormalities associated with endotoxemia.

Conclusions and Clinical Relevance—The protective effect of HBOT was minimal, and results did not support its use as a treatment for horses prior to development of endotoxemia.
A Method for Measuring Some Components of the Pursuit Rotor Skill
Authors: Jahnke John C. , Hammer C. E.
Published: September 2011

A pursuit rotor for measuring some components of skill is described and sample data reported.
A Serial Simple Reaction-Time Circuit
Authors: Mc Cormack P. D. , Bell C. L.
Published: September 2011

A description of a simple reaction time circuit which eliminates the recording of anticipatory responses as non-anticipatory in nature and yet preserves the integrity of the interval of time between the response and the onset of the signal.
An Application of Discriminant Functions to the Problem of Predicting Brain Damage Using Behavioral Variables
Authors: Wheeler Lawrence , Burke Cletus J. , Reitan Ralph M.
Published: September 2011

Discriminant functions were applied to 24 behavioral indices from each of 140 individuals tested in the Neuropsychology Laboratory, Indiana University Medical Center. The scores came from 11 Wechsler subtests, 11 Halstead subtests, and 2 Trail Making tests. Comparisons were made between 61 non-brain-damaged control Ss and 79 Ss showing any of several kinds of cerebral damage on the basis of criteria resulting from independent neurological examination. These 79 were subdivided and compared with the controls as follows: (a) 25 Ss with damage of the left cerebral hemisphere, (b) 31 Ss with damage of the right hemisphere, (c) 23 Ss with diffuse, bilateral involvement. Also the 25 left-damaged and the 31 right-damaged Ss were compared.

The discriminant function in each comparison produced a single weighted score per S, an optimum, least-squares type of separation between the two groups. The resulting distributions of summed, weighted scores in each comparison were inspected for the point of minimum overlap. An individual's weighted score, falling above or below this point, categorized him as belonging to one group or the other. These assignments, when compared with the criterion assignments of Ss to groups, were expressed as percentages of correct predictions: controls versus all categories of cerebral damage, 90.7%; controls versus left damage, 93.0%; controls versus right damage, 92.4%; controls versus diffuse damage, 98.8%, and right versus left damage, 92.9%. Several other indices were examined for percentages of correct prediction, but the discriminant function was superior in all comparisons. A cross-validation study is now in press (6).
Maintenance of Vigilance by Programmed Noise
Authors: Kirk Roger E. , Hecht Elizabeth
Published: September 2011

This research was designed to compare the relative effect of three environmental conditions on the performance of a simple vigilance task. The vigilance task consisted of a cathode ray tube display which was monitored by 30 Ss for 2 hr. Three environmental conditions were randomly introduced while S monitored the display. The conditions were a constant noise of 64.5 db, a variable noise having an average SPL of 64.5 db, and a quiet condition of 61 db. The results indicate that the probability of signal detection is higher for the variable noise condition than for the constant noise and quiet conditions. No difference in probability of detection was found between the latter two conditions. An explanation for the facilitating effect of sensory stimulation on vigilance is sought in terms of the alerting and general arousal effects attributed to the reticular activating system.
On the Relation between Response Uncertainty and Reaction Time in Category Judgments
Authors: Behar Isaac
Published: September 2011

Twelve Ss judged 10 stimulus sizes using either 10 or 2 response categories. Average RT was proportional to the log2 of the number of response alternatives. RTs for each stimulus category correlated highly with response uncertainty associated with each category.
Effect of Covert Alterations of Clock Rate upon Time Estimations and Personal Tempo
Authors: Craik Kenneth H. , Sarbin Theodore R.
Published: September 2011

A theoretical approach to the behavioral process of time judgment is presented which stresses the learning of the conventional clock rate. The process of time judgment is seen as having three components: (1) the criterion, the temporal units and rhythm of the ordinary clock, (2) the rate of sensory input, which has many determinants, both intra- and extra-organismic, and which is subject to constant fluctuation, and (3) the rate of the input modulator, which accommodates with the fluctuation of sensory input rates to provide a categorization of input in rhythmical equivalence to the criterion rate of the ordinary clock. General veridicality of time judgment has two prerequisites: (1) practice of clock estimation under a wide range of input conditions to provide a large inventory of sensory input-input modulator (SI-IM) relationships and (2) an accurate assessment of current input conditions. Manipulation of the functioning of the three components of time judgment suggests methods of disrupting the smoothly functioning, implicit categorizing process involved and thus providing greater systematic understanding of it. Several such possibilities are indicated. The present study investigated the effects of covert alterations of clock rate upon time judgment and personal tempo. We found that over a series of corrected time judgments in which the method of verbal estimation was used and in which the clock rate was covertly altered, the time judgments shifted in the direction of the new clock rate, both when the clock rate was increased relative to ordinary clock rate and when it was decreased. In addition, it was found that covert alteration of clock rate has a differential effect upon two measures of personal tempo. When the altered clock rate was faster than ordinary clock rate, the rate of tempo was relatively greater than when the altered clock rate was less than ordinary clock rate. Self-reports of Ss indicated a wide range of awareness of the alteration in clock rate and of correct understanding of the experimental situation. Further uses of the methodology of alterations in clock rate in conjunction with the psychophysical method of adjustment were suggested for investigations of the subjective passage of time.
Influence of Knowledge of Results on Performance in a Monitoring Task
Authors: Hardesty Don , Trumbo Don , Bevan William
Published: September 2011

Vigilance performance was tested in six independent groups with a modified version of the Mackworth Clock Test. The groups constituted a 3 × 2 design with (a) no knowledge of results, observer-presented knowledge of results, and machine-presented knowledge of results as one dimension, and (b) physical presence or absence of an observer in the test cubicle as the other variable. All groups were retested without knowledge of results one and seven days after the initial test. On the initial test day, groups with no knowledge of results and machine-presented knowledge of results showed the typical decrement function throughout the session. In contrast, Ss receiving verbal knowledge of results from the experimenter showed less decrement and a significantly higher over-all performance. The superiority of the groups receiving the verbal report persisted on the two subsequent test days despite the fact that all extrinsic knowledge of results was withdrawn on these tests. Observer-presented knowledge facilitated performance regardless of the physical presence or absence of the observer in the test cubicle.
Effect of Knowledge of Site of Stimulation on the Threshold for Pressure Sensitivity
Authors: Meyer Victor , Gross Charles G. , Teuber Hans-Lukas
Published: September 2011

Ordinarily, sensory thresholds are determined under conditions where S knows which part of a sensory surface will be stimulated. The present experiment was done under varying degrees of uncertainty regarding site of stimulation. Modified von Frey hairs were applied in normal adults under the following conditions: (1a) to one palm, (1b) to one thumb, (2) one palm and ipsilateral thumb, (3) both palms, (4) palm and contralateral thumb, (5) both palms and one thumb. Under Conditions 2–5, stimuli were applied successively to the various sites in a randomized sequence, with separate reports required for each stimulation. The thresholds increased from those obtained under the traditional method (single site) to the various multiple-site conditions, in the order indicated (1–4), with the last two conditions (4 and 5) equivalent. Thus, increasing uncertainty as to site decreased sensitivity measures, particularly when both sides of the body were engaged and when the sites of stimulation were nonhomologous.
Verbal Reaction Times to Briefly Presented Words
Authors: Pollack Irwin
Published: September 2011

Verbal reaction times were obtained for briefly presented words of vocabularies of different size. Reaction times increased with vocabulary size: initially, the increase was about 26 msec/bit; after four months of testing, the increase was about 13 msec/bit.
Sinusoidal Electrical Stimulation of the Human Vestibular Apparatus
Authors: Dzendolet Ernest
Published: September 2011

Sinusoidal electrical stimulation with eight frequencies ranging from 0.030 to 4.0 cps was applied between the mastoid processes of five male undergraduate Ss. Only ascending series in the method of limits were used, and the amplitude was increased continuously rather than discretely. Subjective reports of the presence of a sensation, and also of its quality were recorded and used to determine RLs at all the frequencies. An objective technique, using the recorded sideways movements of Ss, was developed and also used to determine RLs. These curves of RL versus frequency are termed electrical vestibulograms. The reported qualities were classed into three main categories, (a) swaying sideways, (b) swaying forward and backward, and (c) sideways oscillation of head and body. Subjective and objective electrical vestibulograms were similar in shape, being U-shaped between 0.50 and 4.0 cps, and approximately linear between 0.030 and 0.50 cps, but with the subjective having a slope of about one, and the objective, of zero. The latter vestibulogram was lower than the former. Sway frequencies were also estimated, using a new technique, and were found to be proportional to the stimulus, but the proportionality varied with the frequency. Fluctuation in amplitude of swaying to a constant amplitude stimulus was observed separately in two Ss at each of two frequencies. The results were interpreted as supporting a central, rather than peripheral, adaptation hypothesis.
A Factor-Analytic Study of Daydreaming and Conceptually-Related Cognitive and Personality Variables
Authors: Singer Jerome L. , Antrobus John S.
Published: September 2011

This report summarizes a study of the factorial composition of a series of measures of the structure and content of daydreaming behavior. The relationships of fantasy to measures of divergent thought productivity, attention, curiosity, and personality measures are examined.
Ocular Tracking as a Measure of Autokinetic Movement
Authors: Cormack Robert H.
Published: September 2011

A method for measuring autokinetic movement in which S fixates the apparent starting point of the movement rather than the stimulus light has been developed. Reliability data and theoretical considerations point to the potential usefulness of this measure as a dependent variable for studying effects which are localized in the visual field.
Subcortical Substrate of Autonomic and Psychological Stress
Authors: Weiner Herman
Published: September 2011

The present study was designed to investigate the thesis that both autonomic and psychological stress are related to the degree of parkinsonian symptom-severity, and further, that the psychological indices are related to autonomic malfunctioning. These hypotheses were largely confirmed for the sample used in this study. A moderate degree of association obtained between symptom-severity and the subjective perception of stress. A substantial degree of association was demonstrated between symptom-severity and autonomic stress. The subjective perception of stress and the psychologists' stress-adequacy ratings were, respectively, substantially and markedly related to autonomic stress. The results suggest the superiority of genotypic measures of stress such as conductance rates of change and ratings of stress-adequacy made by experienced psychologists. Finally, the results point up the potential significance of the subcortical underpinnings of psychological behavior.
Effects of Subliminal Stimulation on Imagery and Discrimination
Authors: Fiss Harry , Goldberg Franklin H. , Klein George S.
Published: September 2011

In two separate investigations ( Ns = 13, 24), Ss drew spontaneously arising images after exposure of a subliminal visual stimulus. They then tried to discriminate the stimulus when it was again exposed subliminally. While the stimuli exerted a marked effect on Ss' images, they failed to influence Ss' discriminatory ability. It was concluded that a stimulus too faint to be consciously perceived can nevertheless have a pronounced effect on another mode of conscious experience—in this case, imagery.
Comparison of Blind and Sighted Subjects in the Discrimination of Texture
Authors: Stellwagen William T. , Culbert Sidney S.
Published: September 2011

The ability of 50 blind and 50 sighted Ss to discriminate all combinations of pairs of 10 embossed textural patterns was compared. No group differences were found, and rank order of pattern discriminability showed high agreement.
Angular Displacement of Visual Feedback in Motion and Learning
Authors: Gould John , Smith Karl U
Published: September 2011

The main hypothesis was that angular displacement of the visual feedback of motion produces no disturbance of behavior within a limited “normal” range, but that a breakdown angle can be found beyond this range which will produce disturbance in motion control in proportion to the magnitude of the feedback displacement. Experimental results concerning maze tracing and circle drawing specifically supported the hypothesis. In circle drawing, both compensatory visual displacement errors and direct motor error in control of the pattern of motion conformed to the theoretical assumptions. In addition, data on learning in the two tasks conformed to theoretical assumptions that specific sensory-feedback factors determine differences in motor learning and that the spatial properties of such feedback determine the level of performance during learning. The guiding hypothesis was derived from a neurogeometric conception of brain function, which assumes that each internuncial cell acts as a space detector to record the angular difference between a given neural state of a movement and its sensory feedback. The data contribute positively to our understanding of the brain mechanism of motion and of the sensory process as a neurogeometric detector system. The experiments also define the significance of the methods of sensory-feedback analysis in disclosing the nature of intrinsic geometric relationships between the sensory and motor systems that determine learning and the organization of motion.
Monitoring Readily Detected Auditory Signals and Detection of Obscure Visual Signals
Authors: Binford John R. , Loeb Michel
Published: September 2011

Twenty-four Ss were required to detect infrequently and randomly occurring visual and auditory signals under six different schedules. In four of the sessions there were 40 visual signals and, respectively, 0, 20, 40, or 80 auditory signals. In two sessions there were 20 visual signals and 20 or 60 auditory signals. Auditory signals (increments in a steady noise background) were relatively easy to detect; visual signals (double jumps of a moving clock hand) were relatively difficult to detect. Missed detections of visual signals increased with time on task for each condition. Latency of response to visual signals increased progressively for all conditions except the one with no auditory signals (control condition). Latency was least for this control condition but decreased monotonically with number of auditory signals in other conditions. Visual missed responses were intermediate in frequency for the control conditions and apparently decreased monotonically as a function of the ratio of auditory to visual signals in the other conditions. Latency was higher for conditions with more visual signals, but no such simple relationship is apparent for missed detections.
Judgment of Filled and Unfilled Durations: Intersensory Factors
Authors: Goldstone Sanford , Goldfarb Joyce Levis
Published: September 2011

Previous studies have shown a consistent intersensory difference in absolute judgments of the duration of continuous auditory and visual inputs. More visual than auditory clock time was judged equivalent to specific temporal concepts. Two experiments investigated this intersensory phenomenon further by comparing the judgments of filled auditory and visual durations with the estimation of unfilled intervals bounded by discrete lights and sounds. Auditory durations were judged longer than visual for the filled and unfilled conditions, and filled auditory durations were judged longer than unfilled auditory intervals The intersensory difference in time judgment was independent of stimulus pattern while the filled-unfilled difference was dependent upon sense mode, order effects and internal temporal standard. Stimulus properties must be considered when interpreting the results of time judgment research.
Comments on “Group Paired-Associate Learning: Applicability to the Study of Mediated Generalization”
Authors: Cieutat Victor J.
Published: September 2011

Comments are made on a series of studies by Hakes and Jenkins (1962) regarding applicability of a group paired-associate learning method to the study of mediated generalization. It is suggested that their conclusions do not unambiguously follow from their results. A comparison is made regarding relative variability of scores obtained by group versus individual testing.
Long-Term After-Effects following Isolation of a Circumscribed Area of the Skin
Authors: Aftanas Marion , Zubek John P.
Published: September 2011

Isolation of a circumscribed area of the skin on the forearm for a week resulted in an increase in tactual acuity while application of constant light pressure to the same area resulted in decreased tactual acuity. Statistically significant changes in acuity were still evident three days after the experiment. Furthermore, there were suggestions that the after-effects may persist for as long as six days.
Searching for Ten Targets Simultaneously
Authors: Neisser Ulric , Novick Robert , Lazar Robert
Published: September 2011

Ss were given extensive practice in scanning through lists of printed symbols for particular targets. By the thirteenth day, they scanned as rapidly when searching for any of 10 different targets as when searching for any of five, or for one target alone. These results are compatible with the assumption that many subsystems for processing visual information can operate in parallel, at least in situations where a high degree of accuracy is not required.
Verbal and Perceptual Functions after Surgery of Subcortical Structures
Authors: Levita Eric , Riklan Manuel , Cooper Irving S.
Published: September 2011

The cognitive and perceptual performance of 61 parkinsonians was studied as a function of unilateral basal ganglia surgery, specifically, chemothalamectomy and cryothalamectomy. Preoperative comparisons of non-neurological and parkinsonian Ss revealed no significant differences ( p > .05). Three conclusions were warranted. (a) Cryothalamectomy does not adversely affect cognitive functions in the immediate post-operative period with the exception of greater impairment after right cryothalamectomy than after no surgery on some tasks of visual spatial performance not requiring overt verbal responses ( p < .02). (b) Chemothalamectomy does not adversely affect cognition except for greater post-operative impairment on overt verbal performance after left chemothalamectomy than after left cryothalamectomy ( p < .001). (c) Preoperative to long range comparisons revealed no differences between Ss undergoing surgery or no surgery ( p > .05). Significantly shorter periods of time elapsed between successive testing in the case of cryothalamectomy with implications for effectiveness of treatment ( p < .001, < .01). The role of subcortical structures in perceptual processes and in the elaboration of verbal behaviors was discussed.
Steadiness, Handedness, and Hand Preference
Authors: Simon J. Richard
Published: September 2011

This experiment was concerned with the relative performance of the preferred and non-preferred hands in right- and left-handed Ss. Self-classified strongly right-handed and strongly left-handed Ss performed a steadiness task with one hand and then the other. Results indicate that, while over-all performance is significantly better with the preferred hand, steadiness cannot be regarded as a sensitive index of handedness. A predicted interaction between handedness and hand preference was significant for male Ss.
The IES Arrow Dot Performance of Delinquents and Nondelinquents
Authors: Rankin R. J. , Wikoff R. L.
Published: September 2011

The Arrow Dot test was administered to a volunteer group of 57 reformatory inmates and to a comparison group of 64 college students. It was found that the Impulse score discriminates between these groups. Suggestions are made as to the relationship between the AD I score and the Porteus Maze Q score.
Retention of a Skill following Training with and without Instructions to Retain
Authors: Lavery J. J.
Published: September 2011

The effect of knowing the eventuality of retention trials has been tested with three different conditions and 56 female Ss. Ss who are told before training that they will be tested without KR do better than Ss who are either told after training or not told at all. These results cast considerable doubt on the conclusions drawn from previous studies that do not mention explicitly what instructions, if any, were given regarding retention. The results of other studies done on KR variables are also discussed.
Visual Constancy during Movement: 1. Effects of S's Forward and Backward Movement on Size Constancy
Authors: Gregory R. L. , Ross Helen E.
Published: September 2011

A novel method for estimating constancy is described, which is applied to the estimation of size constancy during motion of observers moved passively on a swing in darkness. Ss viewed a circle traced on an oscilloscope tube and arranged to shrink as S approached it and to expand as he moved away. The variation in size of the display was adjusted by E until it appeared of constant size to S during his movement. Constancy was greater during forward than backward movement.
Lateral Dominance as a Factor in the Perception of Non-Symbolic Material
Authors: Hilborn Edwin H. , Conklin Jack E.
Published: September 2011

Equal numbers of right- and left-eyed Ss were used in an experiment to determine the relative efficacy of stereo- versus non-stereo slides with stereoscopic projection for the detection of minor disparities in pairs of photographs. Stimulus materials were photographs of popcorn, with one kernel removed from one picture in each pair. The time required for the detection of the disparate kernel was recorded. Right-eyed Ss proved greatly superior to left-eyed Ss, and the non-stereo pairs of slides more effective than true stereo pairs. While detection times for the four quadrants were significantly different, no significant interaction between eyedness and quadrants occurred, indicating that scanning patterns for the two groups were not significantly different.
School Subject Preference and the Structure of Value Systems
Authors: Bortner Rayman W.
Published: September 2011

Studies by Haggard and his students suggested that personality differences underlie differential superior achievement in school subjects (arithmetic, reading, and language and spelling) among gifted children. His description of these personality differences suggested that these groups might differ in ego strength as measured by the IES Test. In addition, Ss demonstrating preferences for these content areas might differ on measures of field dependence (a single figure drawing and an embedded figures task). Of 122 elderly, institutionalized male Ss 46 indicated a clear preference for arithmetic, 36 for reading, and 40 for language and spelling. The embedded figures task differentiated the arithmetic and reading groups from the language and spelling groups. The IES Test showed differences between the arithmetic preference and the other two preference groups. These differences were on measures of ego strength and impulse expression; there were none on measures of superego functioning.
Influence of Hospitalization on Simple Reaction Time
Authors: Ross J. A.
Published: September 2011

Twelve hospitalized adult male patients' simple reaction time (RT), termination of a visual stimulus, was compared with that of 12 nonhospitalized adult males. Times between stimulus presentations (intertrial interval) were 3, 9, and 15 sec. A counterbalanced order of interval presentation was used. The data showed that both groups responded similarly at the 3- and 15-sec. intertrial intervals, but there was a significant difference between groups at the 9-sec. intertrial interval. The results are discussed in terms of appropriate control groups in psychomotor studies and the differential effect of the intertrial intervals used on the RT of the two groups studied.
Comment on “Controlled Visual Input and Exploratory Activity in C57B1/6J Mice”
Authors: Baron Alan
Published: September 2011

Wimer and Sterns' (1964) failure to observe differences in open-field activity as a function of environmental complexity was evaluated in terms of their procedure.
Judgment of Volume from Photographs of Complex Shapes
Authors: Pearson Richard G.
Published: September 2011

Observers were asked to judge the volume reduction of 40 distorted metal containers from photographs. Hypotheses regarding the role of amount of information provided by photographs, complexity of damage to the container, past experience of the observer, and memory for visual forms were tested in a study using 279 college students. Findings revealed judgment accuracy to vary as a complex function of angular disparity between photographs, number of photographs, type of object, stimulus characteristics of individual containers, and degree of distortion. Volume reduction of “square” objects was judged more accurately than that of “round” objects. Individual observers were found to be reasonably consistent from one type of object to another in over- or underestimating volume reduction.
Perception Bibliography: Xiii. Psychological Index, No. 10, 1903
Authors: Ammons C. H. , Ammons R. B.
Published: September 2011

83 references to reports and discussions of perception are listed.
Test of Effects of Past Experience on Perception
Authors: Robinson John S. , Brown Larry T. , Hayes William H.
Published: September 2011

Familiarity failed to enhance perceptibility of patterns (Same-Different thresholds) but did facilitate naming them (Identification thresholds). These results add to the recent accumulation of evidence showing that experience does not modify (and certainly does not create) visual impressions which are present, even in humans, from the first day's exposure to the visual world. It is by means of experience, however, that such an organism eventually comes to terms with these impressions.
Lateral Dominance and Right-Left Discrimination: A Comparison of Normal and Retarded Readers
Authors: Coleman Richard I. , Deutsch Cynthia P.
Published: September 2011

The study examines relationships among lateral dominance, right-left discrimination, and reading retardation in lower socio-economic background public school children. Ss were: Group I, 56 male retarded readers, 9.5 to 12.3 yr. old; Group II, 28 boys and 7 girls, 10.3- to 12.0-yr.-old normal readers; Group III, 26 boys and 4 girls, retarded readers, not differing in age from Group II. There were no significant differences between the normal and retarded reading groups on the Harris Tests of Lateral Dominance or on the Benton Right-Left Discrimination Test own-body items. All groups had difficulty with the other-person items. Results indicate that laterality difficulties do not always accompany reading retardation in children 10 yr. and older.
Measurement of Motor Styles
Authors: Fahrion Nell G.
Published: September 2011

In the attempt to depress and release a spring-loaded hand key slowly and steadily there was a significantly greater expenditure of energy by the preferred hand than by the nonpreferred hand when both performed the task together, but not when performance was independent. The expression of energy by the preferred hand resting passively on the key while the nonpreferred hand performed the depressing-and-releasing task was greater than that of the nonpreferred hand in the passive role. The expenditure of energy with either hand was significantly greater when both performed the depressing-and-releasing operation simultaneously than when one hand performed the task independently with the other resting passively upon the key. Individual differences in performance suggest two motor styles, speed control and tremor control.
Evidence for Acquired Equivalence of Cues in a Perceptual Task
Authors: Ellis Henry C. , Feuge Robert L. , Long K. Kilby , Pegram Vernon G
Published: September 2011

The experiment was designed to test the hypothesis that perceptual performance following various types of stimulus predifferentiation tasks including labeling might depend, not upon the specific features of the labels themselves, but upon differential practice effects presumably associated with the labeling task. 60 Ss were given a multiple shape recognition test following one of three types of pretraining: distinctiveness, equivalence or observation practice. In spite of the fact that all groups received comparable amounts of practice with the stimuli, the equivalence group made fewer correct recognitions than did the observation group, a finding which is inconsistent with a differential practice hypothesis and which is consistent with an acquired equivalence of cues hypothesis.
An Objective Method of Assessing a Stress Syndrome Related to Achievement Motivation
Authors: Thiesen J. Warren , Forgus Ronald H. , Spaner Fred E.
Published: September 2011

An approach to the definition and assessment of a stress syndrome related to achievement motivation is described. Because of the importance it has assumed in some recent psychosomatic hypotheses and because of its broader implications for personality theory and research, a relatively simple and objective means of measuring the intensity of stress referable to this syndrome seemed necessary. Toward this end a standard psychophysiological test procedure was devised. The method yields objective measures of degree and duration of heart-rate elevation in response to tasks emphasizing speed and accuracy pressures. An initial experiment demonstrated the validity of some theoretical constructs underlying the procedure. A retest study demonstrated its replicability and its potential for measuring adaptation to stress. The results indicate that the sustained heart-rate response, as utilized in this procedure, is a sensitive and convenient measure of stress associated with achievement motivation. It is suggested that the test battery and methodology described may be useful in research concerning striving-induced stress and its role in psychosomatic disorders.
Identification of Brain Damage by Flicker Perimetry: A Second Cross-Validation
Authors: Chandler Peter J. , Parsons Oscar A. , Haase Gunter R.
Published: September 2011

Examinations of 100 brain-damaged and 50 non-brain-damaged indicate satisfactory cross-validation of a method for detection of brain damage by flicker perimetry. 73% of the brain-damaged and 70% of the non-brain-damaged were correctly identified.
Reminiscence in Inverted Alphabet Printing as a Function of Degree of EEG Abnormality
Authors: Meier Manfred J.
Published: September 2011

This investigation was designed to test an hypothesized negative relationship between degree of EEG abnormality and amount of reminiscence in motor learning. The learning functions and three measures of reminiscence in inverted alphabet printing under massed practice conditions were compared for two groups of convulsive disorder patients differing in judged degree of EEG abnormality. A markedly abnormal EEG group exhibited significantly less reminiscence than a mildly abnormal EEG group in the absence of reliable differences in pre-rest performance level. A normal reference sample showed a higher level of performance than either neurological sample, but differed significantly in reminiscence only from the markedly abnormal EEG group. The results were interpreted to reflect the influence of central neural variables in the generation and dissipation of I r.
Rate of Learning on a Pursuit Rotor Task at a Constant Work-Rest Ratio with Varying Work and Rest Periods
Authors: Plutchik Robert , Petti Roger D.
Published: September 2011

Five groups of Ss ( Ns of 6 to 8) were rested on a pursuit rotor, using a constant rest-work ratio of 1:2. The work lengths varied from 40 sec. to 5 min.; the rest durations from 20 sec. to 2½ min. The asymptotic mean rates of performance for the groups showed no significant differences. The implications of this finding for the concept of “massed” and “distributed” learning were discussed.