Evolution of an instinct under long-term divergent selection for geotaxis in domesticated populations of Drosophila melanogaster

Long-term divergent selection for geotaxis in lines of Drosophila melanogaster (the fruit fly) is described. After 26 years (600+ generations) of intermittent selection, the mean geotactic scores now remain stable upon relaxed selection, a result suggesting that evolutionary changes have occurred in these lines. Because the stability is not due to genetic fixation (homozygosity) of the lines, it must be due to either close linkage of genes associated with geotaxis (which would not result in enduring change) or the development of new coadapted gene complexes utilizing genes associated with extreme geotaxis expression (which should result in enduring change). Better evidence for the latter hypothesis is obtained from the low, than from the high, line. The notions of coadaptation and genetic homeostasis are considered, as well as the prospective use of the geotaxis lines to study such concepts experimentally. The geotactic behavior expressed in each line is defined as "instinctive": It increases reproductive success and is characteristic of a population.     

Reversal of genetic homeostasis in laboratory populations of Drosophila melanogaster under long-term selection for geotaxis and estimates of gene correlates: evolution of behavior-genetic systems

Among Drosophila melanogaster, divergently selected for geotaxis intermittently over 600 generations (28 years), about 80,000 animals have been analyzed behavior-genetically. Each major chromosome pair from two lines was isogenized on an unselected isogenic background. Measurement of their behavioral effects revealed the relative magnitudes II greater than III greater than X for the negatively geotactic (high) line and X greater than III greater than II for the positively geotactic (low) line. When reversing selection for the now phenotypically stable high and low lines and then repeatedly relaxing the reversals, a new genetic homeostasis in the low line was indicated by the return of the reversed-line average scores towards the low extreme; that is, the low line has attained a stable equilibrium for positive geotaxis, an uncharacteristic behavior and an effect not seen before 1979. This change suggests the recent evolution of a new coadaptation among genes. Although not as conclusive, a similar genetic interpretation is suggested for the high line.     

核心自我评价的代际传递：父母支持和子女基本心理需要满足的链式中介作用

采取整群抽样的方式对407户初中生家庭进行调查,探讨父母支持和子女基本心理需要满足在核心自我评价代际传递过程中的链式中介作用。结果表明：（1）核心自我评价在父母与其初中生子女之间存在代际传递效应;（2）父母支持和子女基本心理需要满足在核心自我评价的代际传递中起链式中介作用;（3）核心自我评价的代际传递效应不存在显著的亲代性别、子代性别、亲子性别差异。研究结果有助于理解核心自我评价的代际传递过程。     

Food-search behavior and its relation to the central excitatory state in the genetic analysis of the blow fly Phormia regina

Dethier (1957) described an aspect of food-search behavior in Phormia regina as the blow fly dance. A hungry fly walks in relatively straight lines with its proboscis retracted until it encounters food (sucrose). After ingesting even a small amount of sucrose, the fly begins making frequent, tight turns, flexes its front tarsi to bring more chemosensory hairs into contact with the substrate and repeatedly extends and retracts its proboscis. Like the central excitatory state (CES), which causes an increase in proboscis extensions to water when a fly is stimulated with sucrose, the dance lasts longer in hungrier flies or with higher sucrose concentrations. It was considered that dance behavior might be an ethologically relevant manifestation of CES. In order to test this hypothesis, dance duration in lines selected for high- and low-CES levels was measured. As predicted, flies from the high-CES line danced longer than those from the low-CES line, and the CES-dance correlation in individual flies was high. This phenotypic correlation disappeared in the F2 generation of a cross between the high- and low-CES lines, a result indicating that the observed variations in CES and dance duration were not caused by the same set of genes. Further characterization of the underlying genetic system showed that several linked autosomal genes with digenic epistatic interactions and a complex pattern of maternal inheritance were responsible for the difference in dance durations between the high- and low-CES lines.     

The Effects of Residential Crowding Experience on Reactivity to Laboratory Crowding and Noise1

Sixty male and 60 female subjects previously classified as high and low on a residential crowding experience scale participated in an experiment involving a 2 × 3 × 2 × 2 (density, noise, crowding experience, gender) factorial design. The research was undertaken primarily to determine the influence of previous residential crowding experience as tapped by the Crowding Experience Scale (CES) on reactivity to the environmental stressors of noise and crowding. The results indicated that exposure to environmental stressors produced a deleterious effect on complex task performance and generated negative affect in the respondents. Interestingly, respondents who had reported high levels of experience with crowding showed relatively more crowding tolerance by performing significantly better on cognitively complex tasks (complex anagrams and story comprehension) and exhibiting more positive affect in conditions of high density as compared to low experience of crowding respondents. Reactions to noise were not influenced by crowding experience. Thus, prior experience of crowding as measured by the CES appears to influence reactivity to density in other settings.     

A study of the effects of cranial electrical stimulation on attention and concentration.

There have been several anecdotal accounts that cranial electrical stimulation (CES) enhances attention and the ability to learn new tasks in a normal population, but only one published investigation confirms that CES improves attention using the Alpha Stim CES (Madden and Kirsch, 1987). The purpose of this study was to corroborate the findings of Madden and Kirsch, using more precise measures of attention, such as a Continuous Performance Test (CPT). A pretest and posttest CPT was given to two groups using the LISS CES device. The control group consisted of twenty-one subjects who received the placebo treatment. The experimental group of thirty-one subjects received twenty minutes of CES. Four measures of the CPT show significant gains in attention: Number of Hits, p =.010 Hit RT ISI Change, p =.016, Risk Taking, p =.055; and Attentiveness, p =.054. Based on subjects who demonstrated improvement by one standard deviation on two different measures of the CPT, thirty-one percent of the experimental group improved versus four percent of the control group. The use of CES as a method of increasing attention is a promising area that requires further investigation.     

A rehabilitative program for central executive deficits after traumatic brain injury

Deficits affecting Central Executive System (CES) of working memory (WM) are the main neuropsychological outcome after traumatic brain injury (TBI) and can also explain deficits in other domains, like divided attention, executive functions and long-term memory. For this reason we developed a rehabilitative program based on CES functions and we expected to find an improvement in WM as well as in those cognitive functions controlled by the CES.The experimental group was composed by 9 TBIs, selected for WM deficits, whereas the control group was composed by 6 TBIs, without WM deficits, but with speed processing deficits. All patients performed a cognitive training, based on PASAT (Gronwall & Wrightson, 1981)and two new versions of this task.The results showed in the experimental group an improvement in WM and in the cognitive functions controlled by the CES, whereas control patients did not show any improvement after the cognitive training.     

A study of the effects of cranial electrical stimulation on attention and concentration

There have been several anecdotal accounts that cranial electrical stimulation (CES) enhances attention and the ability to learn new tasks in a normal population, but only one published investigation confirms that CES improves attention using the Alpha Stim CES (Madden and Kirsch, 1987). The purpose of this study was to corroborate the findings of Madden and Kirsch, using more precise measures of attention, such as a Continuous Performance Test (CPT). A pretest and posttest CPT was given to two groups using the LISS CES device. The control group consisted of twenty-one subjects who received the placebo treatment. The experimental group of thirty-one subjects received twenty minutes of CES. Four measures of the CPT show significant gains in attention: Number of Hits,p=.010 Hit RT ISI Change,p=.016, Risk Taking,p=.055; and Attentiveness,p=.054. Based on subjects who demonstrated improvement by one standard deviation on two different measures of the CPT, thirty-one percent of the experimental group improved versus four percent of the control group. The use of CES as a method of increasing attention is a promising are that requires further investigation.     

Attention to local form information can prevent access to semantic information.

Humphreys and Boucart (1997) have shown that when processing of local form is required for response, surrounding global information is automatically processed to a semantic level. The generality of this effect was investigated in two experiments in which the perceptual load of the relevant local form information was manipulated, as was uncertainty about perceptual load. Participants attended to a single line segment inside a picture of an animal or a vehicle and then decided which of two pictures in the target/distractor display that followed contained a line segment that matched the first in orientation. The perceptual load of the relevant local form information was either low (the matching line segment was one of the solitary line segments presented in the centre ofthe target and distractor pictures), or high (the matching line segment was part of one of the solitary letters presented in the centre of the target and distractor pictures). The semantic relations among the pictures were manipulated, and when perceptual load remained constant across trials, semantic relations affected performance in the low-load but not in the high-load condition. When perceptual load varied from trial to trial, there was no evidence of any semantic processing on either low- or high-load trials. The results suggest that in form-matching tasks, attentional priority can be given to local information, thus preventing access to semantic information derived from global shape. They further suggest that the distribution of attention is not dictated entirely by the actual perceptual demands of the relevant stimulus, indicating an important role for top-down processing.     

Comparative effects of microcurrent stimulation on EEG spectrum and correlation dimension

Two mathematical derivatives of electroencephalogram (EEG), Fast Fourier Transform (FFT), and correlation dimension from chaos analysis were used to assess the objective effects of earlobe versus mid-trapezius microcurrent stimulation on brain EEG. These measures were considered to be clinically relevant since low points in the FFT have been associated with attention deficit disorder, and declining correlation dimension has been associated with onset of epilepsy. Thirty Subjects (30) were assigned randomly to one of three groups: earlobe, trapezius, and a double blind placebo control Earlobe stimulation (CES) was hypothesized to alter BEG since research suggests CES enters the brain directly, through a perineural or vascular path via the auditory meatus. Results showed that trapezius microcurrent therapy proved more effective in producing significant declines in FFT spectral smoothing, with an average standard deviation (SD) in the FFT of 1.1, as compared to the CES group showing an SD of 2.9. Correlation dimension in both trapezius and CES stimulation groups increased significantly (p<.001) as compared to placebo, with the correlation dimension measures for earlobe, trapezius, and placebo being 5.7, 5.6, and 3.7, respectively. The author discusses the significance of using body points for promoting clinically beneficial effects in brain electrophysiology as evidenced by improved FFT and correlation dimension.     

Locus of selectivity in a visual memory task using a color value indicator

Selection of high vs low valued letters from a briefly presented visual array was investigated. An indicator specifying the value of letters occurred before or after the array. Selection could occur during input to memory or during output from memory in the before condition, but only at output in the after condition. Previous research using an alphabetic instruction, which required letter identification prior to selection, attributed selection to output. A color instruction in the -present experiment, not requiring letter identification, showed the locus of selection to be at input. Experiment 2 replicated these findings and used an interference technique to add further support. In addition, contrary to previous findings, these results indicated that the selection process caused no deficit in overall recall.     

Predatory aggression in lines of wild mice selected for interfemale aggression

Mice descending from lines previously selected for high and low levels of interfemale aggression and from a nonselected control line were exposed to live crickets on two consecutive test days. Latencies both to attack and to eat the cricket were recorded. No line or sex differences in attacking were found, although latency to attack decreased over test days. Control line mice were more likely to engage in the eating of the cricket than either the high or low selected lines, suggesting that the selection procedure may have dissociated attacking and eating components of predatory behavior.     

Children's detection and awareness of textual anomaly

Children of 8 and 11 years were assessed in two experiments for their sensitivity to textual anomaly. In Experiment 1, subjects read stories containing two target lines, one appropriate and the other anomalous in relation to previously given information. Both age groups read the anomalous line more slowly than the appropriate line, but in a subsequent test of comprehension monitoring, the older group was more likely than the younger group to pick out the anomalous line as not fitting in with the rest of the story. Experiment 2 produced similar results: both 8- and 11-year-old children read an anomalous line more slowly, but 11-year-olds were more likely than 8-year-olds to cite the anomalous line or part of it when questioned about the possible presence of a line that did not fit in with the rest of the story. The results indicate that an age change in comprehension monitoring as indexed by citation or selection of a textual anomaly need not be contingent upon a parallel age change in constructive processing as indexed by modulation of reading rate.     

知觉负载影响注意选择和冲突解决的系列效应

研究考察了无关侧抑制项引起的侧抑制效应如何受到当前试次知觉负载和先前试次知觉负载与目标?侧抑制项关系的交互影响。被试在视觉搜索集中搜索目标朝向刺激(水平或竖直朝向)并作辨别反应, 非目标项在低负载条件下彼此朝向一致, 在高负载条件下彼此朝向不一致。在搜索集的左侧或右侧存在一个与当前目标一致或不一致的无关侧抑制项(flanker)。结果发现, 整体上, 在当前试次低负载条件下会产生较大的干扰效应, 而在当前试次高负载下无干扰效应。此外, 先前试次(trial n-1)为高负载条件时, 当前试次(trial n)出现了典型的知觉负载效应, 即低负载条件干扰效应较大, 高负载条件无干扰效应。但是, 先前试次为低负载条件时, 当前试次的干扰效应大小受到先前试次冲突解决状态的影响。先前试次为低负载条件且目标?无关侧抑制项不一致时, 下一试次低负载条件的侧抑制效应显著减小, 与高负载条件没有差异; 反之, 先前试次为低负载且目标?侧抑制项一致条件时, 下一试次低负载条件的侧抑制效应显著增大。先前试次为低负载条件时, 完成了知觉加工的侧抑制项或者引发了冲突效应(不一致条件), 或者促进了对目标的反应(一致条件), 造成不同的注意选择和冲突解决状态, 显著影响了下一试次的行为表现。这说明, 注意选择与冲突控制过程是动态变化的, 除了受到当前试次知觉负载的影响, 也受到先前试次注意选择和冲突解决状态的调节。     

双字词整词加工与词素加工在眼跳目标选择中的作用

为探讨整词与词素加工在眼跳目标选择中的作用,本研究采用眼动追踪技术,实验1操纵了目标词的词频（高频、低频）和目标词首字字频（高频、低频）;实验2操纵了目标词的词频（高频、低频）和尾字字频（高频、低频）。结果发现：首字字频不影响眼跳目标选择。尾字字频影响眼跳目标选择,当目标词为低频词时,高频尾字条件下从前目标词到目标词的眼跳长度显著地短于低频字条件;当目标词向前眼跳从尾字发出且目标词为低频词时,高频尾字下的眼跳长度显著地长于低频条件。词频影响眼跳目标选择,高频词条件下跳进和跳出目标词的眼跳长度均长于低频词条件。结果表明整词与尾字词素的加工负荷影响随后的眼跳计划,加工负荷越低随后所计划的眼跳长度越长,尾字词素的加工受整词加工的调节,整词与词素加工以混合表征的方式影响眼动控制。     

Detection and Selection Decisions with Conditional Feedback: Interaction of Task Uncertainty and Base Rate

Effects of task uncertainty on decision thresholds in a multiple cue decision task were examined under two types of feedback and three base rate conditions. In most such decision experiments, participants receive feedback after every trial (full feedback) with a single (usually .5) base rate. Our experiment explored conditional (decision‐contingent) feedback, in a task representing a detection problem (passenger screening) in which the decision maker receives no feedback unless the decision is positive (search the passenger). Increased uncertainty made all dependent measures worse. Task uncertainty had detrimental effects on both judgment and decision making, and interacted with effects of feedback and base rate. Decision performance was better with full feedback than with conditional feedback, but not by much. There may be no single unifying explanation for results of our base rate manipulation. Conditional feedback generally resulted in fewer positive decisions than full feedback, but not in the low (.1) base rate condition. Results provide partial support for constructivist encoding and for accuracy maximization with moderate and high base rates, but not with a low base rate. Our results indicated lower selection rates with conditional feedback compared with full feedback in moderate and high base rate conditions, and a more exploratory strategy with higher selection rates with conditional feedback compared with full feedback when base rate was low. Copyright © 2018 John Wiley & Sons, Ltd.     

Effects of counsellor interpretations and client reactance on social influence and the working alliance

These two studies investigated the main and interaction effects of client reactance and counsellor interpretation discrepancy and style on counsellor social influence and the working alliance. Undergraduate students who were divided into high and low reactant pups listened to low, moderate, or high discrepancy interpretations given by counsellors who used a tentative or absolute interpretation. Contrary to the hypotheses, results showed only one interaction effect for reactance, interpretation discrepancy, and interpretation style. Low reactant participants rated the working alliance higher with tentative interpretations while high reactant participants rated it higher with absolute. High reactant participants consistently tended to perceive the counsellor less positively than low reactant participants. There were unexpected gender differences, suggesting that females saw the counselling more positively in the low discrepancy condition while males did in the moderate. The results were not supportive of an interaction among reactance, discrepancy, and style, but are in line with macro-results in the counselling and psychotherapy literature indicating the primary importance of client variables.     

Load theory of selective attention and the role of perceptual load: Is it time for revision?

Perceptual load hypothesis is proposed as a compromise between early and late theory of selective attention which states that the selection will operate early when the load on perception is high and it will operate late when the load on perception is low. Experimental findings have shown that the perceptual load hypothesis is too simplistic in nature as perceptual load is not the only determinant of selection processes. It is difficult to apply the load hypothesis to explain the occurrence of early selection in low load displays as well as the selection processes that operate on distractor and target stimuli that are a part of the same object. Factors like spatial proximity, cues that manipulate the spatial extent of attentional focus, salience of targets as well as the distractors, and perceptual grouping between the target and the distractors should be taken into account while explaining the selective control of attention. Thus, the perceptual load of the display is one such factor that affects selective attention and goal-directed behaviour, but it is not the only factor to affect the selective control of attention.     

Do They Get What They Want or Are They Stuck With What They Can Get? Testing Homophily Against Default Selection for Friendships of Highly Aggressive Boys. The TRAILS Study

In this study a homophily selection hypothesis was tested against a default selection hypothesis, to answer whether preferred and realized friendships of highly aggressive boys differed. In a large peer-nomination sample, we assessed who highly overt aggressive, low prosocial boys (n = 181) nominated as friends (preferred friendships) and who among the nominated friends reciprocated the friendship (realized friendships). These preferred and realized friendships were compared with those of less aggressive (n = 1,268) and highly aggressive but also prosocial boys (bi-strategics; n = 55). Results showed that less aggressive boys preferred peers low on aggression, whereas highly aggressive and bi-strategic boys preferred peers not particular high or low on aggression. In line with default selection, highly aggressive boys ended up with aggressive peers even though that was not their preference. In general, received support proved an important determinant of highly aggressive, bi-strategic, and less aggressive boys’ preferred and realized friendships. Especially highly aggressive boys preferred emotionally supportive friends, but ended up with the least supportive peers. In sum, for friendships of highly overt aggressive boys, the evidence favors default selection over homophily selection.     

Awareness of the saccade goal in oculomotor selection: Your eyes go before you know

The aim of the present study was to investigate how saccadic selection relates to people’s awareness of the saliency and identity of a saccade goal. Observers were instructed to make an eye movement to either the most salient line segment (Experiment 1) or the only right-tilted element (Experiment 2) in a visual search display. The display was masked contingent on the first eye movement and after each trial observers indicated whether or not they had correctly selected the target. Whereas people’s awareness concerning the saliency of the saccade goal was generally low, their awareness concerning the identity was high. Observers’ awareness of the saccade goal was not related to saccadic performance. Whereas saccadic selection consistently varied as a function of saccade latency, people’s awareness concerning the saliency or identity of the saccade goal did not. The results suggest that saccadic selection is primarily driven by subconscious processes.