Dorsal and ventral visual streams: Typical and atypical development

The literature on visuospatial processing describes two distinct pathways within the brain: a dorsal route extending from the visual cortex into the parietal lobes that is critical for spatial processing and a ventral route extending from the visual cortex into the temporal lobes that is critical for form perception. These visual streams appear to differ in their developmental trajectories and their vulnerabilities to diverse neurodevelopmental conditions. The present work aims to investigate development and vulnerability in two aspects of dorsal and ventral visual-stream function, namely attention to location and attention to identity. In Study 1, we compare typically-developing (TD) youth aged 9 to 16 years with young adults aged 18 to 22 years on computerized location and identity tasks. In Study 2, we compare children and adolescents who have congenital hypothyroidism (CH), a pediatric endocrine disorder, with age-matched TD controls on the same tasks. The results from Study 1 show that the youths were less accurate than the adults at judging identity, whereas both groups were equally accurate at judging location. The results from Study 2 show that the youths with CH were slower but not less accurate than the TD youths in making both identity and location judgments. The results are interpreted as signifying later development of ventral (identity) stream functions compared to dorsal (location) but equal vulnerability of both functions in CH.     

Ultrasound: A Window to the Womb?: Obstetric Ultrasound and the Abortion Rights Debate

This paper explores the rhetoric of obstetric ultrasound technology as it relates to the abortion debate, specifically the interpretation given to ultrasound images by opponents of abortion. The tenor of the anti-abortion approach is precisely captured in the videotape, Ultrasound: A Window to the Womb. Aspects of this videotape are analyzed in order to tease out the assumptions about the (female) body and about the access to truth yielded by scientific technology (ultrasound) held by militant opponents of abortion. It is argued that the ultrasound images do not offer transparent confirmation of the ontological status of the embryo and fetus. Rather, the window of ultrasound is constructed through a complex combination of visual and verbal devices: ultrasound images, photographic images, verbal argument, and emotional appeal.     

Experimental disclosure and its moderators: a meta-analysis

Disclosing information, thoughts, and feelings about personal and meaningful topics (experimental disclosure) is purported to have various health and psychological consequences (e.g., J. W. Pennebaker, 1993). Although the results of 2 small meta-analyses (P. G. Frisina, J. C. Borod, & S. J. Lepore, 2004; J. M. Smyth, 1998) suggest that experimental disclosure has a positive and significant effect, both used a fixed effects approach, limiting generalizability. Also, a plethora of studies on experimental disclosure have been completed that were not included in the previous analyses. One hundred forty-six randomized studies of experimental disclosure were collected and included in the present meta-analysis. Results of random effects analyses indicate that experimental disclosure is effective, with a positive and significant average r-effect size of .075. In addition, a number of moderators were identified.     

What good are positive emotions in crises? A prospective study of resilience and emotions following the terrorist attacks on the United States on September 11th, 2001

Extrapolating from B. L. Fredrickson's (1998, 2001) broaden-and-build theory of positive emotions, the authors hypothesized that positive emotions are active ingredients within trait resilience. U.S. college students (18 men and 28 women) were tested in early 2001 and again in the weeks following the September 11th terrorist attacks. Mediational analyses showed that positive emotions experienced in the wake of the attacks--gratitude, interest, love, and so forth--fully accounted for the relations between (a) precrisis resilience and later development of depressive symptoms and (b) precrisis resilience and postcrisis growth in psychological resources. Findings suggest that positive emotions in the aftermath of crises buffer resilient people against depression and fuel thriving, consistent with the broaden-and-build theory. Discussion touches on implications for coping.     

Caffeine as a performance-enhancing drug in rats: sex, dose, housing, and task considerations

Past animal studies of the performance-enhancing properties of stimulant drugs, such as caffeine, may have suffered from a number of procedural and ethical problems. For example. the housing condition of the animals was often not taken into consideration. As well, endurance tests, such as the forced swim task, sometimes involved ethically (and procedurally) questionable interference with natural swimming behaviour. Some of the manipulations, such as attaching a weight to the swimming animal's tail to increase the difficulty of the task and using mortality as a dependent variable, seem grotesque, even unnecessary. In this experiment, the performance-enhancing effects of caffeine in a modified forced swim task and a dominance task were evaluated using male and female rats as subjects (N=60), housed in either enriched or isolated environments. Analysis indicated that rats respond to caffeine as an interactive function of sex, housing, dose, and task characteristics. It was concluded that performance-enhancing properties of stimulant drugs may be the result of a complex interplay of variables, making simple generalizations questionable.     

Predicting change in self-reported and interviewer-assessed adult attachment: tests of the individual difference and life stress models of attachment change

The study tested the key assumption of the individual difference model of adult attachment change: that people who have experienced certain vulnerability factors will be prone to change attachment styles because they have developed unclear models of self and others that render their attachment models unstable. This model was compared to a life stress model, which states that change occurs as an adaptation to new, interpersonally relevant life circumstances. Changes in self-reported and interviewer-assessed attachment were examined among 94 young adults who were followed over 1 year. Analyses yielded support for the individual difference model for change in both self-reported and interviewer-assessed attachment. The life stress model was supported for change in interviewer-assessed attachment only. Implications for differential change processes for self-reported versus interviewer-assessed aspects of adult attachment are discussed.     

Reinstatement of 2-year-olds' event memory using photographs

This experiment examined 24- and 30-month-olds' understanding of photographs as reminders using a deferred imitation paradigm. The 24- and 30-month-olds visited a laboratory playroom and observed an experimenter demonstrating novel activities. Upon returning after a retention interval, half of the children viewed photographs depicting the activities they had viewed during their first visits as reminders of the event, as well as photographs of activities they had never seen. Children in both the reminder and the no-reminder groups were then asked to complete the originally modelled activities as a test of recall. Results indicate that although 30-month-olds recalled more activities than did 24-month-olds, children in the reminder condition at both ages recalled more activities than children in the no-reminder control condition. Results are discussed in terms of the development of representational understanding and long-term recall in young children.     

Use of visual information in speech perception: evidence for a visual rate effect both with and without a McGurk effect

The McGurk effect, where an incongruent visual syllable influences identification of an auditory syllable, does not always occur, suggesting that perceivers sometimes fail to use relevant visual phonetic information. We tested whether another visual phonetic effect, which involves the influence of visual speaking rate on perceived voicing (Green & Miller, 1985), would occur in instances when the McGurk effect does not. In Experiment 1, we established this visual rate effect using auditory and visual stimuli matching in place of articulation, finding a shift in the voicing boundary along an auditory voice-onset-time continuum with fast versus slow visual speech tokens. In Experiment 2, we used auditory and visual stimuli differing in place of articulation and found a shift in the voicing boundary due to visual rate when the McGurk effect occurred and, more critically, when it did not. The latter finding indicates that phonetically relevant visual information is used in speech perception even when the McGurk effect does not occur, suggesting that the incidence of the McGurk effect underestimates the extent of audio-visual integration.     

Observed classroom behavior of children with ADHD: relationship to gender and comorbidity

Examined hypothesized gender and comorbidity differences in the observed classroom behavior of children with attention deficit hyperactivity disorder (ADHD). The behavior of 403 boys and 99 girls with ADHD, ages 7–10, was compared (a) to observed, sex-specific classroom behavior norms, (b) by sex, and (c) by comorbid subgroups. Boys and girls with ADHD deviated significantly from classroom norms on 15/16 and 13/16 categories, respectively. Compared to comparison girls, girls with ADHD had relatively high rates of verbal aggression to children. Boys with ADHD engaged in more rule-breaking and externalizing behaviors than did girls with ADHD, but the sexes did not differ on more neutral, unobtrusive behaviors. The sex differences are consistent with notions of why girls with ADHD are identified and referred later than boys. Contrary to hypothesis, the presence of comorbid anxiety disorder (ANX) was not associated with behavioral suppression; yet, as hypothesized, children with a comorbid disruptive behavior disorder (DBD) had higher rates of rule-breaking, and impulsive and aggressive behavior, than did children with ADHD alone and those with ADHD+ANX. Elevated rates of ADHD behaviors were also observed in children with comorbid DBD, indicating that these behaviors are truly present and suggesting that reports of higher ADHD ratings in this subgroup are not simply a consequence of negative halo effects and rater biases.     

The color of two alphabets for a multilingual synesthete

Interviews with a multilingual synesthete (MLS), who experiences colored letters for Roman and Cyrillic alphabets and for digits, revealed stable synesthetic experiences over 2 1/2 - 5 years. Colors of Cyrillic letters were based on Roman letters. Four Stroop tests involving both types of letters showed that MLS was able to name print color faster if the colors matched her synesthetic colors, showing that synesthesia is automatic. Letter-naming times for blocks of color were slower than those of actual letters, supporting unidirectionality of synesthesia. Stroop tests with Roman, but not Cyrillic, letters showed MLS acquired new temporary letter-color pairings and her color-naming times for these were not different from those for her original synesthetic colors.