STEREO: A program to analyze stereotyped open field locomotion

In rats, amphetamine produces stereotyped locomotion which is characterized by perseverative movement along a fixed route around the perimeter of an open field. The program described in this paper is designed to facilitate analysis of stereotyped locomotion by measuring the repetitive nature of trips between adjacent quadrants of the apparatus using a method described by Mueller, Hollingsworth, and Cross (1989a) which subdivides locomotion into a series of trip lengths. The program is written in Microsoft QuickBASIC to run on an IBM PC/XT or compatible machine. Data from the program can be read by spreadsheets.     

Hippocampal modulation of nucleus accumbens: behavioral evidence from amphetamine-induced activity profiles

The experiments examined amphetamine-induced locomotion and stereotyped behavior in hippocampal-ablated and control rats for 30 days following surgery. Locomotor counts, stereotypy ratings, and locomotor-time profiles showed that d-amphetamine sulfate produced a selective enhancement of locomotion (cage crosses) at the expense of stereotyped behavior in hippocampal rats relative to normal control rats. This enhancement emerged over the first 2 weeks postsurgery. To examine the role of the striatum in this amphetamine-induced effect, combined hippocampal damage and 6-hydroxydopamine-induced damage of the nucleus accumbens or caudate-putamen were used. These results suggested that amphetamine-enhanced locomotion of hippocampal rats is dependent upon the integrity of the nucleus accumbens and may reflect a change of nucleus accumbens activity relative to caudate-putamen activity. Together these findings suggest that the hippocampus may participate in the control of locomotion by projections that modulate the activity of the nucleus accumbens.     

Effect of sulpiride on amphetamine-induced activity and stereotyped locomotion

To investigate the hypothesis that sulpiride potentiates stereotyped locomotion at an intermediate dose of amphetamine, rats were assigned to one of four treatment groups (n=7 per group): vehicle + saline; 20 mg/kg sulpiride + saline; vehicle + 3.5mg/kg amphetamine; 20 mg/kg sulpiride + 3.5 mg/kg amphetamine. An automated tracking system was used to record distance moved and sequences of movements between quadrants in a circular open-field. The results showed that amphetamine increased horizontal distance moved, and increased the number and proportion of thigmotaxic trips around the perimeter of the apparatus. Sulpiride reduced amphetamine-induced hyperactivity and the number of perimeter trips, but had no effect on the proportion and maximum run length of perimeter trips. Thus sulpiride reduces the hyperactivity produced by an intermediate dose of amphetamine, but does not appear to affect the stereotyped nature of locomotion under the drug.     

One-sided limb preference is linked to alternating-limb locomotion in anuran amphibians

Amphibians provide a unique opportunity for identifying possible links between lateralized behaviors, locomotion, and phylogeny and for addressing the origin of lateralized behaviors of higher vertebrates. Five anuran species with different locomotive habits were tested for forelimb and hind limb preferences during 2 stereotyped behavior sequences--wiping a foreign object off their snout and righting themselves from the overturned position. The experiments were analyzed in a broader context of previous findings on anuran lateralization involving 11 anuran species that were studied within the same experimental paradigms. This analysis shows that one-sided forelimb and hind limb motor lateralization in anurans is strongly associated with alternating-limb locomotion and other unilateral limb activity. Conclusions reached for anuran amphibians may be applicable to other vertebrates possessing paired appendages-the degree of lateralization in motor response depends on the mode of locomotion used by a species.     

A NEUROBIOLOGICAL ALTERNATIVE TO THE PERCEPTUAL REINFORCEMENT HYPOTHESIS OF STEREOTYPED BEHAVIOR: A COMMENTARY ON “SELF-STIMULATORY BEHAVIOR AND PERCEPTUAL REINFORCEMENT”

A perceptual reinforcement theory of stereotyped movements is advanced by Lovaas, Newsom, and Hickman (1987) in an effort to integrate a number of diverse observations about the origins and maintenance of this behavior. We, in turn, argue that the theory, as presented, is logically flawed and fails to take into account important biological findings and theory concerning pathological stereotyped acts. An alternative theory, derived primarily from neurological concepts, is briefly described.     

Illusory motions induced by rapid displacements of the observer

Some illusory effects of movement are described that are easily observable when the subject is in rapid locomotion (driving a car or travelling on a train) and gazes fixedly at a particular point of the scene. These effects are essentially characterized by deformations and displacements of parts of the environment. It is suggested that the phenomenon responsible for them is the loss of size and position constancy, respectively. Experimental evidence indirectly validates this hypothesis, and a program of studies is now under way to further corroborate it.     

Objective assessment of gender roles: Gender Roles Test (GRT-36)

This study was designed to develop a computerized test to assess gender roles. This test is presented as a decision-making task to mask its purpose. Each item displays a picture representing an activity and a brief sentence that describes it. Participants have to choose the most suitable sex to perform each activity: man or woman. The test (Gender Roles Test, GRT-36) consists of 36 items/activities. The program registers both the choices made and their response times (RTs). Responses are considered as stereotyped when the chosen sex fits stereotyped roles and non-stereotyped when the chosen sex does not fit stereotyped roles. Individual means (RTs) were computed for stereotyped and non-stereotyped responses, differentiating between domestic and work spheres. A "D" score, reflecting the strength of association between activities and sex, was calculated for each sphere and sex. The study incorporated 78 participants (69% women and 31% men) ranging from 19 to 59 years old. The results show that: (a) reading speed does not explain the variability in the RTs; (b) RTs show good internal consistency; (c) RTs are shorter for stereotyped than for neutral stimuli; (d) RTs are shorter for stereotyped than for non-stereotyped responses. Intended goals are supported by obtained results. Scores provided by the task facilitate both group and individual detailed analysis of gender role, differentiating the gender role assigned to men from that assigned to women, at the domestic and work spheres. Obtained data fall within the scope of the genderology and their implications are discussed.     

The goal of locomotion: Separating the fundamental task from the mechanisms that accomplish it

Human locomotion has been well described but is still not well understood. This is largely true because the observable aspects of locomotion—neuromuscular activity that generates forces and motions—relate to both the task solution and the problem being solved. Identifying the fundamental task achieved in locomotion makes it possible to critically evaluate the motor control strategy used to accomplish the task goal. We contend that the readily observed movements and activities of locomotion should be considered mechanism(s). Our proposal is that the fundamental task of walking and running is analogous to flight, and should be defined in terms of the interaction of the individual’s mass with the medium in which it moves: a low-density fluid for flight, or the supporting substrate for legged locomotion. A rigorous definition of the fundamental task can help identify the constraints and opportunities that influence its solution and guide the selection of appropriate mechanisms to accomplish the task effectively. The results from robotics-based modeling studies have demonstrated how the interaction of the mass and substrate can be optimized, making the goal of movement a defined trajectory of the individual’s mass. We assessed these concepts by evaluating the ground reaction forces generated by an optimization model that satisfies the task but uses none of the mechanisms that are available to the human leg. Then we compared this model to normal human walking. Although it is obvious that the specific task of locomotion changes with a variety of movement challenges, clearly identifying the fundamental task of locomotion puts all other features in an interpretable context.     

Constitutional hypermobility as a problem in the rehabilitation of "vertebragenous" pain syndromes

Load-dependent pain in the locomotion system in generally a sign of muscular incoordinations. The type of muscle disturbance is used as an indicant for purposeful physiotherapy. Patients with "constitutional hypermobility" belong to the physiotherapeutic problem patients. Such patients show signs of minimal brain dysfunction like those described by Janda for adults. It is suspected that constitutional hypermobility is only a single expression of a complex motor control disturbance in which muscular hypotonia plays an important role. This always involves considerable problems in connection with rehabilitation.     

An infrared device to monitor discrete ambulatory and stereotypic behaviors

An electronic device that can detect discrete ambulatory and stereotypic behaviors of animals is described. The system involves a minimum of two infrared (IR) beams, each connected to a set/reset flip-flop or latch. The initial occlusion of an IR beam simultaneously sets a latch, delivers a locomotion pulse output, and resets any previously set latch whose IR beam is not occluded. A set latch causes its associated IR beam to be refractory to further locomotion movements until reset by the occlusion of a second IR beam. All beams are continuously responsive to stereotypic activity.     

The effect of feeling stereotyped on social power and inhibition

An experience sampling study examined the degree to which feeling stereotyped predicts feelings of low power and inhibition among stigmatized and nonstigmatized individuals. For 7 days, participants with a concealable (gay and lesbian), a visible (African American), or no identifiable stigma recorded feelings of being stereotyped, of powerlessness, and of inhibition immediately following social interactions. For members of all three groups, feeling stereotyped was associated with more inhibition, and this relation was partially mediated by feeling low in power. Although stigmatized participants reported feeling stereotyped more often than nonstigmatized participants, they reacted less strongly to the experience, consistent with the presence of buffering mechanisms developed by those living with stigma. African Americans appeared to buffer the impact of feeling stereotyped more effectively than gay and lesbian participants, an effect that was partly attributable to African Americans' higher identity centrality.     

The flip side of perception-action coupling: locomotor experience and the ontogeny of visual-postural coupling.

The possible role of motor development on psychological function is once again a topic of great theoretical and practical importance. The revival of this issue has stemmed from a different approach to the topic, away from Gesell's interest in the long-term prediction of psychological functions from early motoric assessments, toward an attempt to understand how the acquisition of motor skills orchestrates psychological changes. This paper describes how the acquisition of one motor skill, prone locomotion, has been linked to developmental changes in an infant's ability to regulate posture based on information available in patterns of optic flow. It is argued that the onset of prone locomotion presses the infant to differentiate spatially delimited regions of optic flow to effectively and efficiently control the important subtasks nested within the larger task of locomotion, namely, steering, attending to the surface of support, and maintaining postural control. Following this argument, a research program is described that aims to determine if locomotor experience is causally linked to improvements in the ability to functionalize peripheral optic flow for postural control or whether locomotor experience is merely a maturational forecaster of such improvements. Finally, a hypothesis is put forward that links the emergence of wariness of heights to infants' ability to regulate posture on the basis of peripheral optic flow. The paper's overarching theoretical point is the principle of probabilistic epigenesis, which states that one developmental acquisition produces experiences that bring about a host of new developmental changes in the same and different domains.     

Initial environment influences amphetamine-induced stereotypy: subsequently environment change has little effect

Saline-treated and amphetamine-treated (7 mg/kg, ip, immediate) male rats from a Sprague-Dawley substrain were observed in two test environments designed to elicit different investigative responses in normal rats. Snout contact with the substrate was generated by placing the rat in a small enclosed cage. Absence of snout contact was induced by placement of the rat on a square elevated platform. Detailed ethological records were kept of locomotion, rearing, sitting, grooming, gnawing, and sleeping throughout the 90-min session. Amphetamine-treated rats incorporated environmentally contingent bodily postures into their forms of stereotyped behavior. The postures were characteristic of those evinced initially by the saline-treated rats in the same test environment. The control rats showed appropriate changes in their investigative behavior when the apparatus was changed at 10 and at 30 min postinjection. The amphetamine-treated rats, however, were completely unresponsive to such changes at 30 min and only partially so at 10 min postinjection. It was concluded that there is a temporal gradient of decreasing readiness to modify repetitive behavior after a single, large dose of amphetamine.     

Social Acceptability of Hypothetical Married Couples and Their Relationships

The present experiment tested whether the physical attractiveness attributed to members of married couples would vary according to the social acceptability associated with their interconnected leader-follower roles. American college students rated female and male hypothetical stimulus persons who were described as married to each other. As predicted, both partners who were described as being in a traditional relationship with the husband as leader were stereotyped as being highly attractive. Partners in relationships that deviated from this pattern were stereotyped as being less attractive: Those enacting equal leadership roles were intermediate in attractiveness, and those with the wife as leader were least attractive. Gender identity also varied according to the social acceptability of the couple's roles, with the wife and husband in the traditional relationship being stereotyped as most highly sex typed. The personal attributes of self-esteem and social status were not affected by the social acceptability of the couple's relationship. Regardless of sex, these attributes varied according to the strength of the individual's leadership role. As a consequence, the husband's characteristics were either consistently positive or negative for the different leadership conditions; the wife's attributes were inconsistent.     

The relation between gender schemas and adults' recall of stereotyped and counterstereotyped televised information

The relation between adults' gender-related personality characteristics and memory for gender-stereotyped and counterstereotyped televised information was examined. Eighty middle-class undergraduates, equally divided by gender (92% Caucasian and 8% minority groups), viewed a television program that presented two plots: one was traditionally gender-stereotyped and the other was counterstereotyped. Three weeks after viewing, students answered questions assessing their recall of stereotyped and counterstereotyped information that had been presented in the television program. Masculinity and femininity scores were also assessed. Results indicated that gender aschematic adults recalled more counterstereotypical information than did gender schematic adults. Results were interpreted within an information processing model.The authors thank the students of Georgetown University who participated in this research.     

WOMEN IN A NURSING HOME Living with Hope and Meaning

A series of reminiscing-type groups for women in a nursing home is described. The purpose of this project is to use a qualitative methodology for exploring feelings and providing emotional catharsis in a population stereotyped largely by hopeless affect and lack of meaning in their lives. The women in the groups varied widely in physical and cognitive abilities; many were confused and memory-impaired. A rationale is provided for the therapist/leader's directive approach in the context of an egalitarian, feminist orientation. Results point toward an increase in interaction with others in the nursing home environment, more self-awareness and self-esteem, and a heightened empathy for other group participants. Annotated excerpts from three group sessions are included.     

An on-line exact small-sample test of significance for extended matching tasks

An extension of the traditional matching paradigm that enables researchers to test a variety of new experimental hypotheses is outlined. An on-line computer program that provides an exact small-sample test of hypotheses in the extended matching paradigm is described. The program, which has an intuitive graphical interface, may be accessed and executed via the Internet by using an ordinary browser.     

A programmable proximity-contact sensor to detect location or locomotion of animals

A simple electronic device to detect location or to track locomotion of small animals is described. The device is based on anantenna effect—it responds to a change in capacitance as the body of the animal passes between an antenna and one of a series of contact plates. A digital address system is incorporated that is capable of electronically polling the contact plates according to instructions from a data-acquisition system (DAS). Any DAS capable of generating an address of two bits or more and of reading a one-bit data line may be employed. The device is ideal for mazes or other apparatus in which the exclusion of stereotypical behaviors is desired.     

Competition in stereotyped domains: Competition,social comparison,and stereotype threat

The current work examines a novel and specific way in which competition can hurt the performance of negatively stereotyped individuals: by evoking stereotype threat. In four experiments, we demonstrate that women's underperformance in math when primed with competition was due to feeling worried about confirming negative stereotypes about women's math ability (i.e., stereotype threat), that the activation of negative performance stereotypes for women primed with competition was due to increased group‐level social comparisons (i.e., comparing the self with men and women), and that priming competition led men to perform more poorly than women in a domain where they are negatively stereotyped (i.e., verbal ability). This research suggests that priming people with competition in contexts where they are negatively stereotyped leads to greater social comparison, activation of negative stereotypes, and concern about confirming these stereotypes, thereby decreasing stereotyped individuals' performance in the stereotyped domain. Copyright © 2013 John Wiley & Sons, Ltd.     

A note on modulations and structuring of locomotion in children and adults

The aim of this study was to investigate the modulations of locomotion induced by a rhythmic cognitive task (counting one's steps). Subjects (6- and 8-year-olds and adults) were requested to walk freely, and then to walk while counting their steps. Here a decrease in cadence values was observed in children only, with quasi-total repercussions on velocity at the age of 6 only. The spatiotemporal structuring of locomotion described here is already present at 6 years of age and is not altered in the step-counting situation: strong links were observed between cadence and velocity, and between stride length and velocity, and weak links between cadence and stride length.