An assessment of the technique and clinical application of visual evoked response measurements

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Analysis of variables measured in the visual screening of University of Birmingham freshmen and a critical review of visual screening methods and approach

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Modulation of long-range neural synchrony reflects temporal limitations of visual attention in humans

Because of attentional limitations, the human visual system can process for awareness and response only a fraction of the input received. Lesion and functional imaging studies have identified frontal, temporal, and parietal areas as playing a major role in the attentional control of visual processing, but very little is known about how these areas interact to form a dynamic attentional network. We hypothesized that the network communicates by means of neural phase synchronization, and we used magnetoencephalography to study transient long-range interarea phase coupling in a well studied attentionally taxing dual-target task (attentional blink). Our results reveal that communication within the fronto-parieto-temporal attentional network proceeds via transient long-range phase synchronization in the beta band. Changes in synchronization reflect changes in the attentional demands of the task and are directly related to behavioral performance. Thus, we show how attentional limitations arise from the way in which the subsystems of the attentional network interact. The human brain faces an inestimable task of reducing a potentially overloading amount of input into a manageable flow of information that reflects both the current needs of the organism and the external demands placed on it. This task is accomplished via a ubiquitous construct known as “attention,” whose mechanism, although well characterized behaviorally, is far from understood at the neurophysiological level. Whereas attempts to identify particular neural structures involved in the operation of attention have met with considerable success (1-5) and have resulted in the identification of frontal, parietal, and temporal regions, far less is known about the interaction among these structures in a way that can account for the task-dependent successes and failures of attention. The goal of the present research was, thus, to unravel the means by which the subsystems making up the human attentional network communicate and to relate the temporal dynamics of their communication to observed attentional limitations in humans. A prime candidate for communication among distributed systems in the human brain is neural synchronization (for review, see ref. 6). Indeed, a number of studies provide converging evidence that long-range interarea communication is related to synchronized oscillatory activity (refs. 7-14; for review, see ref. 15). To determine whether neural synchronization plays a role in attentional control, we placed humans in an attentionally demanding task and used magnetoencephalography (MEG) to track interarea communication by means of neural synchronization. In particular, we presented 10 healthy subjects with two visual target letters embedded in streams of 13 distractor letters, appearing at a rate of seven per second. The targets were separated in time by a single distractor. This condition leads to the “attentional blink” (AB), a well studied dual-task phenomenon showing the reduced ability to report the second of two targets when an interval <500 ms separates them (16-18). Importantly, the AB does not prevent perceptual processing of missed target stimuli but only their conscious report (19), demonstrating the attentional nature of this effect and making it a good candidate for the purpose of our investigation. Although numerous studies have investigated factors, e.g., stimulus and timing parameters, that manipulate the magnitude of a particular AB outcome, few have sought to characterize the neural state under which “standard” AB parameters produce an inability to report the second target on some trials but not others. We hypothesized that the different attentional states leading to different behavioral outcomes (second target reported correctly or not) are characterized by specific patterns of transient long-range synchronization between brain areas involved in target processing. Showing the hypothesized correspondence between states of neural synchronization and human behavior in an attentional task entails two demonstrations. First, it needs to be demonstrated that cortical areas that are suspected to be involved in visual-attention tasks, and the AB in particular, interact by means of neural synchronization. This demonstration is particularly important because previous brain-imaging studies (e.g., ref. 5) only showed that the respective areas are active within a rather large time window in the same task and not that they are concurrently active and actually create an interactive network. Second, it needs to be demonstrated that the pattern of neural synchronization is sensitive to the behavioral outcome; specifically, the ability to correctly identify the second of two rapidly succeeding visual targets

Normative contrast sensitivity values for the back-lit Melbourne Edge Test and the effect of visual impairment

Background: The Melbourne Edge Test (MET) is a portable forced-choice edge detection contrast sensitivity (CS) test. The original externally illuminated paper test has been superseded by a backlit version. The aim of this study was to establish normative values for age and to assess change with visual impairment. Method: The MET was administered to 168 people with normal vision (18-93 years old) and 93 patients with visual impairment (39-97 years old). Distance visual acuity (VA) was measured with a log MAR chart. Results: In those eyes without disease, MET CS was stable until the age of 50 years (23.8 ± .7 dB) after which it decreased at a rate of ≈1.5 dB per decade. Compared with normative values, people with low vision were found to have significantly reduced CS, which could not be totally accounted for by reduced VA. Conclusions: The MET provides a quick and easy measure of CS, which highlights a reduction in visual function that may not be detectable using VA measurements. © 2004 The College of Optometrists.

Retrieval of implicit inhibitory processes:the impact of visual field, object-identity, and memory dynamics

After exogenously cueing attention to a peripheral location, the return of attention and response to the location can be inhibited. We demonstrate that these inhibitory mechanisms of attention can be associated with objects and can be automatically and implicitly retrieved over relatively long periods. Furthermore, we also show that when face stimuli are associated with inhibition, the effect is more robust for faces presented in the left visual field. This effect can be even more spatially specific, where most robust inhibition is obtained for faces presented in the upper as compared to the lower visual field. Finally, it is revealed that the inhibition is associated with an object’s identity, as inhibition moves with an object to a new location; and that the retrieved inhibition is only transiently present after retrieval.

Center of shelf attention:understanding the role of visual attention on product choice

Two eye-tracking studies and an offline experiment explored the effect of central shelf location on attention and choice. Investigation of the attention process revealed that the central gaze cascade effect, progressively increasing attention focused on the central option predicted choice.

Visually induced syncope:a nonepileptic manifestation of visual sensitivity?

Visual sensitivity, defined as the “susceptibility toward experiencing seizures, which are triggered by the physical characteristics of visual stimuli and not by their perceptual properties,”1 can manifest in the context of various forms of generalized or focal, idiopathic or symptomatic epilepsies.2 We report a patient with no family or personal history of epilepsy who presented episodes of loss of consciousness exclusively triggered by visual stimuli unrelated to their emotional content, in which we have documented EEG-EKG characteristics suggestive of a neurally mediated syncope.

The risk of adverse selection and its management in the process of venture capital investment (The experience of Hungarian investors)

Venture capitalists can be regarded as financers of young, high-risk enterprises, seeking investments with a high growth potential and offering professional support above and beyond their capital investment. The aim of this study is to analyse the occurrence of information asymmetry between venture capital investors and entrepreneurs, with special regard to the problem of adverse selection. In the course of my empirical research, I conducted in-depth interviews with 10 venture capital investors. The aim of the research was to elicit their opinions about the situation regarding information asymmetry, how they deal with problems arising from adverse selection, and what measures they take to manage these within the investment process. In the interviews we also touched upon how investors evaluate state intervention, and how much they believe company managers are influenced by state support.

An evaluation of child welfare inservice training: The relative effectiveness of substance abuse content in improving worker knowledge and attitudes

Given the seriousness of substance abuse as a child welfare problem, the purpose of this study was to examine the relative effectiveness of an inservice training curriculum for child welfare workers. The training was designed to improve worker knowledge and attitudes in working with substance abusing families. Seventy (70) child welfare workers from public and private agencies in two south Florida counties participated in a pretest/posttest control group design that also trained and retested the control group. The literature review supports that the general preparedness of child welfare workers for the issues presented by substance abusing families is in question. Confounding this problem is a lack of understanding of substance abuse dynamics, worker biases, and predispositions. The two research hypotheses focused on whether inservice training could increase worker knowledge and improve worker attitudes in working with this population. Training delivery was in the form of a five-day inservice focusing on an array of substance abuse knowledge and attitudinal topics. Separate knowledge and attitude instruments were developed for the research and were administered, before and after training, to a purposive sample of participants that were randomly assigned to the experimental and control groups. The data analysis supported the research hypotheses but raised a question. Specifically, the experimental group demonstrated significant improvement in posttest scores on both instruments after receiving the training; whereas the control group, with training withheld, also demonstrated a significant improvement at posttest, but only on the knowledge instrument. Although the question was unanswered, when examined at a more critical significance level, only the experimental group remained significant. The hypotheses were reconfirmed when, after training and retesting, the control group also displayed significant improvement on both instruments. The findings support the conclusion that this substance abuse inservice was effective in improving worker knowledge and attitudes regarding working with substance abusing families. As an implication for social work practice, it suggests that similar inservice training can be a viable training resource when formal substance abuse training is unavailable. Additional research is suggested regarding to what degree increased substance abuse knowledge and improved worker attitudes correlate with improved practice.

A comparison of the leadership styles of the leaders at New World School of the Arts

The purpose of this study was to determine if the perceived leadership styles of the leaders at New World School of the Arts were different according to their roles in the organization. The study focused on the top leaders of the organization: the Provost who heads the college program, and the Principal who heads the high school program.^ The Leadership Practices Inventory (LPI) Self and Observer developed by Kouzes and Posner (1990) was used to examine and compare the perceived differences between the leaders and the programs. The LPI measures five practices of exemplary leadership. The LPI Self and Observer was administered to the leaders, administrative subordinates, and faculty. In addition to the LPI a Demographic Inventory was used to collect data about the respondents.^ This study used a causal-comparative design to determine if differences existed between the leaders at NWSA as perceived by the leaders themselves and their respective administrative subordinates and faculty. T tests were conducted on the mean differences between the five leadership practices measured by the LPI. All tests were declared significant if exceeding the 5% level $(p={<}.05).$^ Significant differences were found within the college program across all five practice areas. To a lesser degree, significant differences were found within the high school in three practice areas: Inspiring, Enabling, and Modeling. Three significant differences were found between the college and high school in two practice areas, Enabling and Encouraging.^ There is little consensus of opinion within the college regarding the operative leadership style. Within the high school there is substantial similarity of perception regarding the operative leadership style. There is substantial similarity of perception between the programs regarding the operative leadership style. ^

The effects of peer teaching of infant massage on general elf-efficacy and mother infant attachment among mothers in a residential rehabilitation facility for drug addiction and substance abuse

Approximately 200 million people, 5% aged 15-64 worldwide are illicit drug or substance abusers (World Drug Report, 2006). Between 2002 and 2005, an average of 8.2% of 12 year olds and older in the Miami, Fort Lauderdale metropolitan areas used illicit drugs (SAMHSA, 2007). Eight percent of pregnant women, aged 15 to 25, were more likely to have used illicit drugs during pregnancy than pregnant women aged 26 to 44. Alcohol use was 9.8% and cigarette use was 18% for pregnant women aged 15 to 44 (SAMHSA, 2005). Approximately a quarter of annual birth defects are attributed to the exposure of drugs or substance abuse in utero (General Accounting Office, 1991). Physical, psychological and emotional challenges may be present for the illicit drug/substance abuse (ID/SA) mother and infant placing them at a disadvantage early in their relationship (Shonkoff & Marshall, 1990). Mothers with low self efficacy have insecurely attached infants (Donovan, Leavitt, & Walsh, 1987). As the ID/SA mother struggles with wanting to be a good parent, education is needed to help her care for her infant. In this experimental study residential rehabilitating ID/SA mothers peer taught infant massage. Massage builds bonding/attachment between mother and infant (Reese & Storm, 2008) and peer teaching is effective because participants have faced similar challenges and speak the same language (Boud, Cohen, & Sampson 2001). Quantitative data were collected using the General Self-Efficacy and Maternal Attachment Inventory-Revised Scale before and after the 4-week intervention program. A reported result of this study was that empowering ID/SA mothers increased their self-efficacy, which in turn allowed the mothers to tackle challenges encountered and created feelings of being a fit mother to their infants. This research contributes to the existing database promoting evidence-based practice in drug rehabilitation centers. Healthcare personnel, such as nurse educators and maternal-child health practitioners, can develop programs in drug rehabilitation centers that cultivate an environment where the ID/SA rehabilitating mothers can peer teach each other, while creating a support system. Using infant massage as a therapeutic tool can develop a healthy infant and nurture a more positive relationship between mother and infant.

A Study of Teacher Efficacy of Special Education Teachers of English Language Learners with Disabilities

This research examined the perceived teacher efficacy of special education teachers of English Language Learners with disabilities. The results demonstrate the positive correlation between proficiency in the language of the target students and teacher efficacy. An analysis of responses yielded two major themes, organizational and teacher issues, affecting teacher performance.

The Framing of the Aftermath of the Chicago Teacher’s Strike

The study explores the framing of the Chicago teachers strike in the media. The study uses content analysis of text from major media sources to find major themes in frames, theorize their purpose, and explore the reaction to them of teachers as public intellectuals.

The effect of sexist attitudes on the perception of visual artists by community college and university students

This study compared the effects of sexist labeling on the perceptions of visual artists by the community college and university students and determined their sex role orientation. The 370 students were shown five slides of an artist's works and were given six versions of an artist's biography. It contained embedded sexual labeling (woman, girl, person/ she, man, guy, person/he). The Artist Evaluation Questionnaire was administered to the female and male community college and university students that required the students to evaluate the female and male artists on several aspects of affective and cognitive measures. The questionnaire consisted of 9 items that had to be rated by the participants. In addition, the students filled out the Demographic Questionnaire and the BEM Sex Role Inventory, titled the Attitude Questionnaire. The Analysis of Variance testing procedures were administered to analyze the responses. The results disclosed gender differences in students' ratings. The female artist's work, when the artist was referred to by the neutral sexual label, "person", received significantly higher ratings from the female students. The male students gave the female artist her highest ratings when she was referred to by the low status sexual label, "girl". Both sexes did not express statistically significant preferences for any of the male sexual labels. Gender difference became apparent when it was found that female students rated both sexes equally, and their ratings were lower than those of the male students. The male students rated the female artist's work higher than the work of the male artist. The analysis of the sex role inventory questionnaire revealed the absence of the feminine (expressive) and masculine (instrumental) personalities among the students. The personalities of almost all the students were androgynous, with a few within the range of the near feminine, and a few within the range of the near masculine. The study reveals that there are differences in perception of sexual labels among the community college and university students.

The Effects of Peer Teaching of Infant Massage on General Self-Efficacy and Mother Infant Attachment Among Mothers in a Residential Rehabilitation Facility for Drug Addiction and Substance Abuse

Approximately 200 million people, 5% aged 15-64 worldwide are illicit drug or substance abusers (World Drug Report, 2006). Between 2002 and 2005, an average of 8.2% of 12 year olds and older in the Miami, Fort Lauderdale metropolitan areas used illicit drugs (SAMHSA, 2007). Eight percent of pregnant women, aged 15 to 25, were more likely to have used illicit drugs during pregnancy than pregnant women aged 26 to 44. Alcohol use was 9.8% and cigarette use was 18% for pregnant women aged 15 to 44 (SAMHSA, 2005). Approximately a quarter of annual birth defects are attributed to the exposure of drugs or substance abuse in utero (General Accounting Office, 1991). Physical, psychological and emotional challenges may be present for the illicit drug/substance abuse (ID/SA) mother and infant placing them at a disadvantage early in their relationship (Shonkoff & Marshall, 1990). Mothers with low self efficacy have insecurely attached infants (Donovan, Leavitt, & Walsh, 1987). As the ID/SA mother struggles with wanting to be a good parent, education is needed to help her care for her infant. In this experimental study residential rehabilitating ID/SA mothers peer taught infant massage. Massage builds bonding/attachment between mother and infant (Reese & Storm, 2008) and peer teaching is effective because participants have faced similar challenges and speak the same language (Boud, Cohen, & Sampson 2001). Quantitative data were collected using the General Self-Efficacy and Maternal Attachment Inventory-Revised Scale before and after the 4-week intervention program. A reported result of this study was that empowering ID/SA mothers increased their self-efficacy, which in turn allowed the mothers to tackle challenges encountered and created feelings of being a fit mother to their infants. This research contributes to the existing database promoting evidence-based practice in drug rehabilitation centers. Healthcare personnel, such as nurse educators and maternal-child health practitioners, can develop programs in drug rehabilitation centers that cultivate an environment where the ID/SA rehabilitating mothers can peer teach each other, while creating a support system. Using infant massage as a therapeutic tool can develop a healthy infant and nurture a more positive relationship between mother and infant.