Arousal effects on evoked activity in a "nonsensory" system

Responses from motor cortex evoked by cerebellar stimulation have been recorded with chronically implanted electrodes from cats in different states of arousal. The response, which in the waking cat consists of a short latency biphasic component followed by one or more slower waves, was attenuated, or abolished completely, in association with electroencephalographic and behavioral signs of decreased arousal. In contrast, responses in primary somatosensory cortex evoked by stimulating the bulbar trigeminal nucleus were enhanced during periods of decreased alertness.     

A quantifiable behavioral correlate of psychotogen and tranquilizer actions

A representative psychotogen, lysergic acid diethylamide (LSD-25), in doses small enough to be devoid of gross effects, increases response latency in rats to a tone indicating the availability of water reward; this effect is greatly reduced by prophylactic administration of a representative phenothiazine tranquilizer, chlorpromazine (CPZ), in doses that per se do not affect performance. The nature of the chlorpromazine action and its competition with lysergic acid diethylamide is revealed by the effects of chlorpromazine in larger doses.     

Human auditory frequency-following responses to a missing fundamental

Both a complex tone perceived as a 365-hertz "missing fundamental" and a 365-hertz pure tone evoked 365-hertz far-field frequency-following responses. Narrow-band masking noise centered at 365 hertz attenuated the responses to the pure tone but not to the complex tone. Results support the concept that perception of the missing fundamental is based on periodic neural activity.     

Somatically evoked magnetic fields of the human brain

The human brain is found to produce a magnetic field near the scalp which varies in synchrony with periodic electrical stimulation applied to a finger. Use of a highly sensitive superconducting quantum interference device as a magnetic field detector reveals that the brain's field is sharply localized over the primary projection area of the sensory cortex contralateral to the digit being stimulated. The phase of the response at the stimulus frequency varies monotonically with the repetition rate and at intermediate frequencies yields a latency of approximately 70 milliseconds for cortical response.     

Temporal order judgement and reaction time

A model which predicts judgment of the temporal order of stimuli from simple reaction time is proposed. Visual data show covariation of the two measures with luminance changes, and suggest that (i) temporal order judgments reflect a biased response criterion and (ii) the motor component of reaction time has little variability relative to variance in receptor system latency.     

1-delta9-tetrahydrocannabinol: neurochemical and behavioral effects in the mouse

Administration of pure 1-delta(9)-tetrahydrocannabinol to mice had the following dose-dependent nzeurochemical and behavioral effects: a slight but significant increase in concentrations of 5-hydroxytryptamine in whole brain; a decrease in concentration of norepinephrine in brain after administration of low doses and an increase after high doses; diminished spontaneous activity, mloderate hypothermnia, hypersetisitivity to tactile and auditory stimiuli, and ataxia after low doses; and sedation, pronounced hypothermia, and markedly diminished spon taneous activity and reactivity after high doses. The duration of the effects on body temperature and spontaneous activity correlated generally with the changes in brain amines. The characteristic changes in brain amines do not correspond exactly to those observed with other psychotropic drugs.     

Sleep after exercise

After moderate treadmill exercise, marked decreases in operant responding and in latency to onset of behavioral sleep occurs in cats. The sleep produced is characterized by enhancement of synchronized electroencephalographic activity with suppression of the desynchronized phase. The result is consistent with the theory that a function of synchronized sleep is to facilitate recovery from fatigue.     

Retrograde amnesia: production of skseletal but not cardiac response gradient by electroconvulsive shock

Rats given a single electroconvulsive shock immediately after but not 60 seconds after an aversive conditioning trial exhibited behavioral retention deficits 24 hours later in a one-trial passive avoidance task. In contrast to these differential performance deficits, similar heart-rate changes, indicative of fear retention, were seen in punished animals irrespective of the time of delivery of the shock. These data suggest retention of a generalized fear to the training experience that was not revealed by the behavioral measure. The potential usefulness of concomitant behavioral and physiological response assessment in consolidation research is discussed.     

Activity and responsivity in rats after magnesium pemoline injections

Rats injected intraperitoneally with magnesium pemoline avoided a buzzing sound (conditioned stimulus) associated with an electric shock to the feet (unconditioned stimulus) more frequently than controls. Drug-injected rats did not avoid the foot shock more frequently than controls, although the experi mental rats did have shorter response latencies fn the active avoidance task. In sub sequent experiments which measured activity changes and response to the buzzing sound alone, it was found that magnesium pemoline caused a lesser decrease in activity level and a more sustained responsivity to the buzzer's. sound than did control injections of tragacanth. This may account for the latency differences observed in the avoidance task.     

Electrical signs of selective attention in the human brain

Auditory evoked potentials were recorded from the vertex of subjects who listened selectively to a series of tone pips in one ear and ignored concurrent tone pips in the other ear. The negative component of the evoked potential peaking at 80 to 110 milliseconds was substantially larger for the attended tones. This negative component indexed a stimulus set mode of selective attention toward the tone pips in one ear. A late positive component peaking at 250 to 400 milliseconds reflected the response set established to recognize infrequent, higher pitched tone pips in the attended series.     

美妙的咏叹感恩的礼赞--论当代女诗人蓝蓝的创作特征

在新时期的诗歌浪潮中，蓝蓝是一位有影响的女诗人，她的作品以素朴、纯粹的情绪，简洁、舒展的句子，宁静、单纯的音响，向人们展示着淳朴真挚的内心世界，充满了爱与美的意趣。后期的创作风格出现了转变，进一步扩张了诗歌的可容性，拓展了诗歌空间。     

Stereoisomers of N-allylnormetazocine: phencyclidine-like behavioral effects in squirrel monkeys and rats

(+/-)-N-Allylnormetazocine is a benzomorphan opioid with psychotomimetic effects. The pure stereoisomers of this compound, as well as the racemic mixture, were compared to phencyclidine for their behavioral effects on squirrel monkeys and rats trained to discriminate phencyclidine from saline. Dose-response determinations were made for responses to phencyclidine, to a racemic mixture of N-allylnormetazocine, and to the pure levo and dextro isomers of N-allylnormetazocine. In both rats and monkeys, the dextro isomer and the racemic mixture produced dose-dependent responses appropriate for phencyclidine; the levo isomer did not produce the responses appropriate for phencyclidine at any of the doses tested. In both species, the levo isomer was more potent than the dextro isomer in decreasing the rate of responding. Thus racemic N-allylnormetazocine is a mixture of compounds that produce different behavioral effects.     

Classical conditioning of pain-elicited aggression

Unconditioned aggression between paired animals in response to electric shock has been previously demonstrated. In this study, with the use of classical Pavlovian conditioning procedures, aggression was produced between paired rats as a response to a tone stimulus.     

Neuronal activity in narcolepsy: identification of cataplexy-related cells in the medial medulla

Narcolepsy is a neurological disorder characterized by sleepiness and episodes of cataplexy. Cataplexy is an abrupt loss of muscle tone, most often triggered by sudden, strong emotions. A subset of cells in the medial medulla of the narcoleptic dog discharged at high rates only in cataplexy and rapid eye movement (REM) sleep. These cells were noncholinergic and were localized to ventromedial and caudal portions of the nucleus magnocellularis. The localization and discharge pattern of these cells indicate that cataplexy results from a triggering in waking of the neurons responsible for the suppression of muscle tone in REM sleep. However, most medullary cells were inactive during cataplexy but were active during REM sleep. These data demonstrate that cataplexy is a distinct behavioral state, differing from other sleep and waking states in its pattern of brainstem neuronal activity.     

农户生计资本对生态退化逆转趋势影响分析

【目的】 研究河西沙化区农户生计资本对生态退化逆转的影响。【方法】 实地调研、农户问卷调查和文献资料收集数据与分析,运用SLA可持续生计框架,构建沙化区农户生计多维评价指标,采用因子分析法和Logistic回归模型,整理分析河西沙化区523份农户调查问卷,研究农户生计资本对生态退化逆转趋势的影响。【结果】 河西沙化区农户生计资本为2.727,其中人力资本为0.358,自然资本为0.283,物质资本为0.681,金融资本为0.454,社会资本为0.609,文化资本为0.350。从农户对河西沙化区生态退化逆转趋势综合响应得分看,纯农户对生态退化逆转响应得分最低,为-0.502,兼农户处于生态退化逆转响应边缘,为-0.053;非农户对生态退化逆转响应度得分为0.32。随着家庭收入增加,农户对生态退化逆转趋势的响应得分度呈现“一”字型缓慢上升。人力资本、物质资本与社会资本对生态退化逆转可持续影响较大,贡献也较大。在Ⅰ组和Ⅱ组中,人力资本每增加一个单位农户对生态退化逆转趋势综合响应转为可持续的发生概率将分别增大e3.752=42.61倍和e2.433=11.39倍,物质资本将分别增大8.13和22.22倍,社会资本将分别增大6.65和1.77倍。【结论】 河西沙化区农户生计资本总体偏低,结构不均衡;纯农户生计资本低,非农户生计资本高。随着纯农户到非农户生计方式的转变,农户对生态退化逆转响应的综合得分不断提高,但纯农户的认知和行为响应对该区域生态退化逆转还没有起到明显的正向促进作用。沙化区农户生计资本中的人力资本、物质资本与社会资本,对生态退化逆转趋势具有重要影响作用。     

歙县许村方言异读及音变现象研究

方言存在异读是一种普遍现象,从歙县许村方言[1]的实际情况看,其异读情况主要有四种表现形式：一是文白异读,二是元音内部屈折变化,三是变调,四是在语音发展中产生的合音现象。而音变则是在语流中由于音节的相互影响而产生的语音变化,从许村方言看,主要是清入与平、上、去三声结合而产生的变化。严格意义上说,它不属于异读,是与异读有本质区别的语音变化形式。对于这两种现象的研究,对于揭示方言语音与中古音韵的联系具有一定的意义。尤其是方言语音内部元音的屈折变化的研究,对于中古汉语是否存在形态变化更具有一定的理论意义。     

Brain stem neurons in modified pathways for motor learning in the primate vestibulo-ocular reflex

The vestibulo-ocular reflex (VOR) stabilizes retinal images by generating smooth eye movements that are equal in amplitude and opposite in direction to head turns. Whenever image motion occurs persistently during head turns, the VOR undergoes motor learning; as a result image stability is gradually restored. A group of brain stem neurons that are in the modified pathways has now been described. The neurons express changes in firing in association with motor learning in the VOR and receive monosynaptic inhibition from the flocculus of the cerebellum. The changes in firing have an appropriate magnitude and are expressed at the correct latency to account for the altered VOR. The response properties of the neurons point to their brain stem vestibular inputs for further investigation of the site of motor learning.     

纯林和混交林3种植物光合特征研究

为探究不同造林模式下植物光合生理响应机制,精准提升人工林改造水平,使用Li−6400XT对黄土丘陵区纯林和混交林中油松、连翘、柠条叶片光合作用日变化及光响应曲线进行测定。结果表明：造林模式并未对3个树种净光合速率日变化趋势产生影响,仅对3个树种净光合速率日变化均值产生影响,具体表现为油松（混交连翘） > 油松（混交柠条） > 油松（纯林）、连翘（纯林） > 连翘（混交油松）、柠条（混交油松） > 柠条（纯林）;在不同造林模式下,影响因子中仅空气相对湿度与净光合速率的关系显示出差异;当光合有效辐射为2000 μmol/(m²·s)时,所有测定植物叶片净光合速率趋于饱和,与纯林相比,油松（混交连翘）、油松（混交柠条）、柠条（混交油松）的净光合速率分别提高了42.1%、10.5%和74.0%,连翘（混交油松）的净光合速率降低了40.4%;采用4种光响应模型拟合光响应曲线,结果显示直角双曲线修正模型效果最优,油松（混交连翘）、油松（混交柠条）光合参数均高于油松纯林,柠条（混交油松）高于柠条纯林。上述结果说明,在黄土丘陵区,相较于纯林,油松与柠条的混交林可加强植物各自的光合能力,环境适应性更强,更适合在该区栽植。     

Computer-based interviewing system dealing with nonverbal behavior as well as keyboard responses

A digital computer has been programmed to conduct a medical interview while simultaneously monitoring the heart rate and keyboard response latency of the respondent for each question frame. The program can branch to new frames contingent upon the heart rate and response latency values, as well as the keyboard responses, and thus alter the course of the interview on the basis of this nonverbal information. The program is presented as a technique for studying the use of nonverbal respondent behavior in automated, clinical interviews.     

;hycomyces: Interference Between the Light Growth Response nd the Avoidance Response

Phycomyces sporangiophores showl a growth response to a light stimus and an avoidance bending response to a physical barrier. A bluie-light stimnlluts Imninisteredl in conjunction with a barrier interferes with the avoidance bending sponse. This interference begins ifter a latency of abotit 3 minultes atndt continues a period of 4 to 5 minutes.