Counterintuitive Direction Research Articles

Direction Selectivity of Neurons in the Striate Cortex Increases as Stimulus Contrast Is Decreased

Various properties of external scenes are integrated during the transmission of information along central visual pathways. One basic property concerns the sensitivity to direction of a moving stimulus. This direction selectivity (DS) is a fundamental response characteristic of neurons in the visual cortex. We have conducted a neurophysiological study of cells in the visual cortex to determine how DS is affected by changes in stimulus contrast. Previous work shows that a neuron integration time is increased at low contrasts, causing temporal changes of response properties. This leads to the prediction that DS should change with stimulus contrast. However, the change could be in a counterintuitive direction, i.e., DS could increase with reduced contrast. This possibility is of intrinsic interest but it is also of potential relevance to recent behavioral work in which human subjects exhibit increased DS as contrast is reduced. Our neurophysiological results are consistent with this finding, i.e., the degree of DS of cortical neurons is inversely related to stimulus contrast. Temporal phase differences of inputs to cortical cells may account for this result.

Acculturation, Parent–Child Acculturation Differential, and Chronic Disease Risk Factors in a Mexican-American Population

Acculturation is typically defined in terms of individual responses to a dominant culture. In the present study, we examined the effects of different levels of acculturation among family members. Specifically, we looked at the health and risk behavior in Mexican-American children as related to a variety of psychosocial predictors, especially the differences in orientation toward Mexican- and Anglo-American cultures between them and their parents. Mother and child pairs (n = 106) noted their orientation toward both Anglo and Mexican cultures. Children's dietary and sedentary behaviors, tobacco and alcohol use (and susceptibility to use), and depressive symptoms were also measured. Males were more likely to be sedentary and consume higher levels of total fat and saturated fat, whereas girls reported higher levels of depression. Anglo-oriented youth consumed lower levels of calories from fat but also more alcohol than did their Mexican-oriented counterparts. The latter was particularly the case among those children who were relatively more Anglo oriented than were their parents. Parent-child acculturation differential in terms of the differences in Mexican orientation, in comparison, predicted susceptibility to tobacco use. However, the sum of the absolute values of these two differences predicted only lifetime alcohol use, and in a counter-intuitive direction. This familial measure of acculturation shows some promise, but additional formative research is needed to operationalize this construct.

A Strange Direction for Static Friction

Except at the Earth's poles and at the equator, a box on a horizontal surface cannot remain at rest relative to the surface unless a very small static friction force acts upon the box. I demonstrate here that in the Northern Hemisphere, the required static friction is in the counterintuitive direction of south to north.

Commentary on Typology of Religious Characteristics of Social Service and Educational Organizations and Programs

In this commentary about Sider and Unruh’s typology, four questions are raised: (a) When religion is visibly expressed, is it the expression of religion? (b) When organizations move within the continuum, do they move in multiple and even counterintuitive directions? (c) How do beneficiaries benefit? (d) How does the “faith factor” figure into macro programs? It is concluded that it is in both what the typology is designed to do and not designed to do that informs future research.

Exchange rates and bertrand oligopoly

The impact of exchange-rate changes on industrial prices seems ambiguous. Incomplete and even “perverse” pass-through has been observed: the import prices in the depreciating country decrease while those in the appreciating country increase. To explain these “counterintuitive” price reactions we consider a situation of international Bertrand competition: two firms, based in different countries, are selling in both countries simultaneously. The profit-maximizing duopolists set the prices for their products in each of the two markets which are segmented on the demand side. We then study the qualitative effect of an exogenous exchange-rate change on the Bertrand-Nash equilibrium. Under the strong assumption of linear demand and cost functions we have “normal” exchange-rate pass-through. However, allowing for more general cost structures in this simple static model enables us to show that the import prices in both countries might move in counterintuitive directions.

The relationship of positive and negative alcohol expectancies to patterns of consumption of alcohol in social drinkers

Negative alcohol expectancies have recently come to occupy a more important position in the expectancy literature, but recent claims that positive expectancies are unimportant in the consumption of alcohol when compared with negative expectancies are based on potentially flawed methodology. This study investigated the relative contribution of positive and negative expectancies to the consumption of alcohol using an instrument designed to measure both positive and negative expectancies. One hundred ninety-three men and women from the general community participated in the study. Findings showed while negative expectancies accounted for the greater proportion of variance of frequency of consumption, positive expectancies remained an important predictor of consumption, accounting for the greater proportion of variance of quantity consumed per session. The interesting but sometimes counterintuitive directions of these relationships can be explained in terms of social learning principles. The relatively neglected concept of negative expectancies is worthy of further use and investigation.

Time to default in the UK mortgage market

This paper employs duration analysis to investigate the timing of default in the UK mortgage market. Our analysis is performed on an ex ante basis, in that our explanatory variables are available to mortgage lenders when the loan is first made. We estimate both standard Weibull distributions and generalizations of the Weibull that permit non-monotonic hazard functions. The models fit the data well, suggesting that we have captured the major sources of variation in duration. We find that ‘cash flow’ variables, such as salary and interest rate paid, play the largest role. Surprisingly, loan-to-value ratios are either insignificant or influence default times in a counter-intuitive direction.

Spatial asymmetry in the photofragmentation of diatomic molecules using coherent control.

A calculation of the spatial distribution of ion emission in the phase-controlled, two-color photodissociation of diatomic molecules in intense, low-frequency laser fields is presented. Using atomic orbitals, we determine the time average of the electronic charge distribution at the critical internuclear separation, the point at which electron localization occurs. We find qualitative agreement with a recent experiment with ${\mathrm{HD}}^{+}$, which shows asymmetry in the counterintuitive direction. We predict that ${\mathrm{H}}_{2}^{+}$ and lower frequencies will give even better agreement. \textcopyright{} 1996 The American Physical Society.

Effects of the intestinal flagellate, Cochlosoma anatis, on intestinal mucosal morphology and disaccharidase activity in Muscovy ducklings

Newly hatched female Muscovy ducklings were randomly separated into 2 groups of 12 and 1 group of 13. Ducklings in the first 2 groups were each orally inoculated with 0.5 ml of sterile normal saline containing 0 and 3 × 10 6 trophozoites of Cochlosoma anatis, respectively. Birds in the third group were each orally inoculated with 3 × 10 6 trophozoites for 5 consecutive days. Birds were weighed daily for the first 5 days and then on days 7, 14 and 21 post-inoculation (p.i.). On days 6, 7, 8, 13, 14, 15, 20, 21 and 22 p.i., 1 bird from each group was killed and samples of intestine at 7 levels were taken for trophozoite counts, mucosal disaccharidase analyses and morphometric analysis. Body weights did not differ among treatment groups at any time during the experiment. Trophozoite numbers did not change over the period 6–22 days p.i. Trophozoite numbers were lowest in the anterior small intestine and increased distally, but very few were observed in the caecum. Crypt depth was greater in all regions of the small intestine in inoculated groups compared to uninoculated controls, and was significantly increased in the duodenum, proximal jejunum and mid-jejunum ( P<0.05). Villus height was greater in inoculated groups compared to controls at all levels of the intestine and was significantly increased in the duodenum, proximal jejunum and ileum ( P<0.05). Mucosal palatinase and maltase activity in the small intestine were reduced in inoculated groups compared to uninoculated controls; palatinase activities were significantly reduced in the proximal and mid-jejunum and maltase activities were significantly reduced in the mid-jejunum ( P<0.05). Sucrase activities were significantly increased at all levels of the small intestine in inoculated ducklings compared to uninoculated controls ( P<0.05). Although no clinical signs were evident, Cochlosoma infection significantly altered intestinal morphometrics and mucosal enzyme concentrations in ducklings, in several cases in a counter-intuitive direction.

The role of data in the EIS process: Evidence from the BLM wilderness review

Various propositions have been offered about the role of the environmental impact statement (EIS) in agency decision making. These include statements that agencies are (1) using the information collected in the EIS to make rational decisions; (2) justifying decisions made a priori; (3) using the EIS to gain support or consensus for projects; or (4) simply fulfilling a legal mandate, with the EIS having no substantive impact on decisions. Previous studies regarding the role of EIS data have focused on the quality of the data in the EIS and whether or not the data are related to decisions. The role of site-specific information in the Bureau of Land Management (BLM) wilderness EIS process is analyzed and the results are used to reflect on the impact of the EIS in agency decision making. These results are compared with an earlier analysis of the Forest Service's Second Roadless Area Review and Evaluation (RARE II). The results of the statistical analyses of three sets of BLM wilderness EISs indicate that although some of the site-specific information about resource potential is statistically related to agency wilderness recommendations, the vast majority of the information is not. In addition, in some cases, the information was related to wilderness recommendations in a counterintuitive direction. Overall, of the 190 measures of resource potential found in these documents, only 17 (9%) were statistically related to BLM recommendations in an intuitive direction. The fact that most of the information in these EISs is not statistically related to decisions lends support to the proposition that the agency was primarily fulfilling the legally mandated procedure of the National Environmental Policy Act in producing these EISs, rather than achieving the spirit of the law. Results from the analysis of the Forest Service's RARE II wilderness review are similar. Although these analyses may provide support for proposals to improve the EIS through shortening of the documents, more research is needed before it can be assumed that shorter EISs will ensure a link between the remaining information and agency decisions.

The role of non—auditory factors in measured and self—reported disability

The effect of age per se on auditory disability in relation to other non-auditory factors, including personality and IQ, is unclear because of the close link with hearing threshold level. Auditory disability may be assessed in terms of either performance or self-report. It was measured using two tasks identifying words in sentences: (1) sentence identification in noise for spatially separated signal sources, and (2) identification of sensible and nonsensical sentences given at normal and artificially accelerated rates. Self-reported disability was assessed using the MRC Institute of Hearing Research's Hearing Disability Questionnaire and the American Hearing Performance Inventory. The sample of 240 individuals aged 50-75 years was constructed to provide a balance across the major stratification parameters of hearing level and age. In accordance with much of the published literature, the performance indices exhibited significant age effects: for a given hearing threshold level, older individuals are more disabled. Conversely, the indices of self-reported disability exhibit a trend whereby individuals with a given hearing threshold level, report a lower degree of disability with increasing age. There were no significant effects of personality, verbal or non-verbal IQ on the performance indices. However, these variables had large effects on reported disability, increasing the explained variance by approximately 20% more than the variance explained by hearing threshold level and age. Thus, the effect of age has the expected direction for performance-based disability, but for reported disability has the counter-intuitive direction. This finding, together with the additional large significant effects of other nonauditory variables, implies that indices of self-reported disability have to be controlled for these other major determinants if they are to be useful in an overall assessment of auditory disability.

Separated fraternal twins: resemblance for cognitive abilities.

Thirty-four pairs of Swedish fraternal twins separated in the first 10 years of life were administered 12 tests of cognitive abilities. The average age of the twins was 59 years. Nineteen pairs were separeted before the first year of life and 26 pairs (76%) were separated by the age of 5 years. Moderate positive twin correlations were found for all tests, reaching significance for Raven's Progressive Matrices and Word Beginnings and Endings. A twin correlation of 0.52 emerged for the first principal component (a measure of general ability). Moderate correlations were found for Spatial Ability and for Verbal Ability/Perceptual Speed factors; for the Memory factor the correlation was lower. The effect of early environment on cognitive ability was assessed by analyzing the association between a degree of separation index and twin resemblance. The importance of the separation measures taken individually was also examined. Some significant effects were found, but these were consistently in a counterintuitive direction: Twins separated earlier weremore similar than those separated later.