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Individuals with schizophrenia have problems with visual contrast processing. The current study investigated contrast sensitivity (CS) in schizophrenia/schizoaffective disorder to elucidate the underlying neural mechanisms affected by this disorder and to identify critical testing conditions that distinguish individuals with the disorder from healthy individuals. Principal component analysis was applied to the data (N = 143) to separate responses from distinct visual pathways. Participants were 68 patients and 75 age‐similar controls. CS was obtained using a forced‐choice psychophysical paradigm with grating patterns of low to high spatial frequency presented at short and long durations. Linear mixed‐effects models were used to examine differences in log CS with respect to group, duration, and stimulus condition. Lower CSs were found in patients compared to controls over all stimulus conditions with the magnitude of deficits dependent on both spatial frequency and stimulus duration. Log CSs to low and high spatial frequencies loaded onto separate principal components, supporting the existence of two psychophysical mechanisms, transient and sustained. Critical conditions were identified to tap each mechanism. Visual acuity was correlated moderately with log CS to high, but not low, spatial frequencies, and deficits found for acuity and CS to moderate/high spatial frequencies (4–21 cycles/degree) appear to reflect dysfunction in the sustained mechanism. CS deficits found at the lowest spatial frequency tested (0.5 cycles/degree) appear to reflect dysfunction in the transient mechanism. Both types of CS deficits may have diagnostic value and implications for social and neurocognitive deficits in this disorder. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to describe the development and validation of a personal growth scale in caregiving partners of persons with multiple sclerosis (MS). Method: Two studies were conducted: one to identify possible constructs and items, and another to and examine the instrument's psychometric properties. Study 1 consisted of focus groups of 39 partners of patients with MS, expert reviews, and qualitative methodology for identifying themes. In Study 2, the items generated were administered to a new sample (N = 315), and the instrument's psychometric properties were assessed. Results: Study 2 sample was suitable for principal component analysis (PCA), and PCA was performed with oblique rotation. A 6-component solution was deemed most parsimonious and interpretable. Subscales were formed and labeled as follows: Positivity, Appreciation, Acceptance, Insight, Independence, and Spirituality. Reliability analysis of the subscales showed acceptable to high internal consistency. A secondary PCA was performed on mean subscale scores. Five of the six subscales clustered together along one dimension, and the sixth, Spirituality, was found to be distinct as represented in a loading plot. This subscale was retained as an independent measure; the remaining subscale scores were summed to create a total score. Measures of convergent and discriminant validity evaluated against existing instruments yielded findings in the expected directions. Conclusions: The dimensionality and structure of personal growth in caregiving partners of persons with MS were delineated in a novel instrument. Future studies should confirm its structure, establish classification criteria, and standardize it as an assessment tool. [ABSTRACT FROM AUTHOR]

ABBREVIATIONS. AA, arachidonic acid; DHA, docosahexaenoic acid; SD, standard deviation; CA, corrected age; EPA, eicosapentaenoic acid; egg-TG, egg-derived triglyceride; SSC, Similac Special Care; SDAY 1, study day 1; EHM-T, exclusively [...], Objectives. A randomized, masked, controlled trial was conducted to assess effects of supplementing premature infant formulas with oils containing the long-chain polyunsaturated fatty acids, arachidonic acid (AA; 20:4n6), and docosahexaenoic acid (DHA; 22: 6n3) on growth, visual acuity, and multiple indices of development. Methods. Infants (N = 470) with birth weights 750 to 1800 g were assigned within 72 hours of the first enteral feeding to 1 of 3 formula groups with or without long-chain polyunsaturated fatty acids: 1) control (N =144), 2) AA + DHA from fish/fungal oil (N = 140), and 3) AA + DHA from egg-derived triglyceride (egg-TG)/fish oil (N = 143). Infants were fed human milk and/or Similac Special Care with or without 0.42% AA and 0.26% DHA to term corrected age (CA), then fed human milk or NeoSure with or without 0.42% AA and 0.16% DHA to 12 months' CA. Infants fed exclusively human milk to term CA (EHM-T; N = 43) served as a reference. Results. Visual acuity measured by acuity cards at 2, 4, and 6 months' CA was not different among groups. Visual acuity measured by swept-parameter visual-evoked potentials in a subgroup from 3 sites (45 control, 50 AA + DHA [fish/fungal]; 39 AA + DHA [egg-TG/fish]; and 23 EHM-T) was better in both the AA + DHA (fish/ fungal; least square [LS] means [cycle/degree] ± standard error [SE; octaves] 11.4 ± 0.1) and AA + DHA (egg-TG/ fish; 12.5 ± 0.1) than control (8.4 ± 0.1) and closer to that of the EHM-T group (16.0 ± 0.2) at 6 months' CA. Visual acuity improved from 4 to 6 months' CA in all but the control group. Scores on the Fagan test of novelty preference were greater in AA + DHA (egg-TG/fish; LS means ± SE, 59.4 ± 7.7) than AA + DHA (fish/fungal; 57.0 ± 7.5) and control (57.5 ± 7.4) at 6 months' CA, but not at 9 months' CA. There were no differences in the Bayley Mental Development Index at 12 months' CA. However, the Bayley motor development index was higher for AA + DHA (fish/fungal; LS means ± SE, 90.6 ± 4.4) than control (81.8 ± 4.3) for infants [is less than or equal to] 1250 g. When Spanish-speaking infants and twins were excluded from the analyses, the MacArthur Communicative Development Inventory revealed that control infants (LS means ± SE, 94.1 ± 2.9) had lower vocabulary comprehension at 14 months' CA than AA + DHA (fish/fungal) infants (100.6 ± 2.9) or AA + DHA (egg-TG/fish) infants (102.2 ± 2.8). There were no consistent differences in weight, length, head circumference, or anthropometric gains. Conclusion. These results showed a benefit of supplementing formulas for premature infants with AA and DHA from either a fish/fungal or an egg-TG/fish source from the time of first enteral feeding to 12 months' CA. Pediatrics 2001;108:359-371; premature infants, docosahexaenoic acid, arachidonic acid, long-chain polyunsaturated fatty acids, infant formulas.

An existing scale of personal growth in caregivers of people with multiple sclerosis (MS) was expanded for use with an acquired brain injury (ABI) population, and was modified following additional psychometric analyses. A cross-sectional online survey was administered to 315 caregiving partners of persons with MS and 310 family caregivers of persons with ABI. Principal component analysis (PCA) performed on the original 32-item instrument yielded a 4-component, 17-item solution with correlated subscales with solid psychometric properties. Subscales were labelled Appreciation, Positivity, Adjustment, and Spirituality. Secondary PCA conducted revealed three subscales (five items each) correlated moderately while the fourth, Spirituality, remained distinct. The sum of the three five-item subscales may serve as a total score. Reliability analysis yielded acceptable-to-high internal consistency. Comparisons of the PGS with existing instruments demonstrated its discriminant/convergent validity. Two kinds of latent class analyses were conducted on the 15-item PGS to identify three latent classes that spanned the neurologic groups, revealing that measurement invariance was held for the instrument in this sample. An instrument with sound psychometric properties was established, designed to assess personal growth in caregivers of individuals with ABI or MS. Future work should explore its value in other populations and as a metric of changes over time. [ABSTRACT FROM AUTHOR]