Use of Functional Magnetic Resonance Imaging in the Early Identification of Alzheimer's Disease

A growing body of evidence suggests that a preclinical phase of Alzheimer's disease (AD) exists several years or more prior to the overt manifestation of clinical symptoms and is characterized by subtle neuropsychological and brain changes. Identification of individuals prior to the development of significant clinical symptoms is imperative in order to have the greatest treatment impact by maintaining cognitive abilities and preserving quality of life. Functional magnetic resonance imaging (fMRI) offers considerable promise as a non-invasive tool for detecting early functional brain changes in asymptomatic adults. In fact, evidence to date indicates that functional brain decline precedes structural decline in preclinical samples. Therefore, fMRI may offer the unique ability to capture the dynamic state of change in the degenerating brain. This review examines the clinical utility of blood oxygen level dependent (BOLD) fMRI in those at risk for AD as well as in early AD. We provide an overview of fMRI findings in at-risk groups by virtue of genetic susceptibility or mild cognitive decline followed by an appraisal of the methodological issues concerning the diagnostic usefulness of fMRI in early AD. We conclude with a discussion of future directions and propose that BOLD-fMRI in combination with cerebral blood flow or diffusion techniques will provide a more complete accounting of the neurovascular changes that occur in preclinical AD and thus improve our ability to reliably detect early brain changes prior to disease onset.     

The hidden persuaders break into the tired brain

There is a long-lasting debate on whether subliminal advertising actually works. In this context there are some studies suggesting that subjects’ motivation is a crucial point. Karremans et al. [Karremans, J. C., Stroebe, W., & Claus, J. (2006). Beyond Vicary’s fantasies: The impact of subliminal priming and brand choice. Journal of Experimental Social Psychology, 42, 792-798] showed that subjects were influenced in their intention to drink a specific brand of soft drink by a subliminally presented brand prime, but only if they were thirsty. In the present study, we adapted their paradigm to the concept of ‘concentration’ and embedded the subliminal presentation of a brand logo into a computer game. Actual subsequent consumption of dextrose pills (of the presented or a not presented brand) was measured dependent on the level of participants’ tiredness and the subliminally presented logo. We found the same pattern as Karremans et al. (2006): only tired participants consumed more of the subliminally presented than the not presented brand. Therefore, the findings confirm that subjects are influenced by subliminally presented stimuli if these stimuli are need-related and if subjects are in the matching motivational state.     

Maternal correlates of 2‐year‐old American Indian children's social‐emotional development in a Northern Plains tribe

The developmental experiences of very young American Indian children today are not well documented in the current literature. The present study sought to explore the social‐emotional development of American Indian toddlers living on a Northern Plains reservation, as a function of maternal variables. Mothers completed self‐report questionnaires about their experiences and their children's development. Observer ratings of children's development also were conducted. Maternal stress, substance use/abuse, perceptions of stress in the mother–child relationship, social support, and American Indian cultural identity were significantly related to children's social‐emotional development. This study is the first to explore these relationships in a Northern Plains American Indian sample of young children and their mothers. Results suggest possible points of intervention for improving the developmental outcomes of very young American Indian children.     

The neighbor and the infinite: Marion and Levinas on the encounter between self,human other,and God

In this article I examine Jean-Luc Marion's two-fold criticism of Emmanuel Levinas’ philosophy of other and self, namely that Levinas remains unable to overcome ontological difference in Totality and Infinity and does so successfully only with the notion of the appeal in Otherwise than Being and that his account of alterity is ambiguous in failing to distinguish clearly between human and divine other. I outline Levinas’ response to this criticism and then critically examine Marion's own account of subjectivity that attempts to go beyond Levinas in its emphasis on a pure or anonymous appeal. I criticize this move as rather problematic and turn instead back to Levinas for a more convincing account of the relations between self, human other, and God. In this context, I also show that Levinas in fact draws quite careful distinctions between human and divine others.     

Resilience in the Face of Maternal Psychopathology and Adverse Life Events

Maternal psychopathology has long been recognized as a risk factor for psychopathology in offspring; however, some resilient youth achieve a favorable outcome in the presence of maternal psychopathology. We identified factors that predicted resilience among youth who were exposed to adverse life events, and also examined whether the same factors protected youth against maternal psychopathology and adverse life events. Main and interaction effects of child and family factors were examined employing cross-sectional data from a household probability sample of 1285 youth aged 9 through 17 collected at four sites. On average, children exhibited a greater degree of resilience when they had higher IQ, closer parental monitoring, better family functioning, higher educational aspiration, and were female. Interaction between maternal psychopathology and IQ was significant, and there was a trend between maternal psychopathology and gender. A higher IQ is a protective factor against both maternal psychopathology and adverse life events; whereas being a girl seems to be a protective factor against maternal psychopathology, but not adverse life events.     

Maltreated Children's Emotional and Behavioral Problems: Do Teachers and Parents See the Same Things?

We examined whether parent/caregivers and teacher/therapists differ in their perceptions of the behavior problems of young maltreated children. The sample consisted of 33 maltreated preschoolers (58% neglected, 24% sexually abused, 18% physically abused, 59% African American, 41% Caucasian) enrolled in a metropolitan-area treatment center providing an educational/intervention program for maltreated children and their families. Most (82%) of the participant families had an annual income of $10,000 or less. Parent/caregivers and teacher/ therapists provided data about the children, employing the Colorado Child Temperament Inventory, Child Behavior Checklist, and Preschool Behavior Questionnaire. The results indicate that the teacher/therapists and the parent/caregivers perceived the same child as behaving differently. Implications concerning how teachers and parents might communicate are discussed, as well as possible reasons for the two different perceptions of the same child. Three potential reasons for the differences are that they are due to the different perspectives of parents and teachers in assessing child behaviors, to situational variation in child behavior (e.g., home versus school), or to some combination of both effects.     

Effect of Age and Level of Cognitive Function on Spontaneous and Exploratory Behaviors in the Beagle Dog

Cognitively characterized young and aged beagle dogs were administered six different spontaneous behavior tests, which provided measures of locomotion, exploration, and social interaction. Consistent with our previous findings, we obtained no overall effect of age on locomotion. We did find, however, that for the aged dogs locomotion correlated with level of cognitive function, being lowest in age-unimpaired dogs and highest in impaired dogs. Exploratory behavior, as measured by response to novelty, varied with age, with young dogs scoring the highest. Young dogs spent more time with novel toys and a person, responded more to a silhouette of a dog, and interacted more with a model dog compared to aged dogs. Among the aged dogs, age-unimpaired dogs spent the greatest amount of time sitting or standing beside a person whereas age-impaired dogs spent the most time reacting to a reflection in a mirror. The age-impaired dogs show undirected, stereotypical types of behavioral patterns. These differences in activity patterns may be linked to underlying age-associated neuropathology.     

Going around transparent and grid‐like barriers: detour ability as a perception–action skill

Early detour ability may not generalize immediately across similar problems in different perception–action systems, but instead may reveal a pattern of developmental onset that is more domain‐specific. To investigate this possibility, we examined how 10‐month‐old (n = 24) and 12‐month‐old (n = 24) infants performed detours via different action modes and around barriers that differed in transparency. Infants made reaching and locomotor detours to retrieve an object located behind either an upright transparent barrier or an upright transparent barrier overlaid with a grid pattern. The results indicated that infants were more likely to make reaching than locomotor detours and explored the transparent and grid barriers differently. Additionally, younger infants more often attempted to contact the object through the entirely transparent barrier than did older infants, especially when making a reaching detour. The results suggest that during detour development, infants learn to coordinate relevant perceptual information with emerging actions.     

Discrimination learning decreases perceived similarity according to an objective measure

Initial identification discriminations between two sizes and between two slants produced better overall performances on subsequent size and slant same-different discriminations, respectively. This size- and slant-specific transfer was due to an improvement on only the different pairs. Time-duration identification discriminations with the identical stimuli and response assignments improved neither overall same-different performances nor performances on different pairs. A good performance on different pairs relative to same pairs should indicate a low perceived similarity. The literature indicates that A-X and B-Y pairings produce a positive transfer on an A-versus-B discrimination when X and Y are relatively low in similarity, and also indicates that a low perceived (not physical) similarity improves discrimination learning. An increase in salience should have also improved performance on the same pairs. The conclusion: the initial discriminations decreased the perceived similarity of parts (size or slant). This decrease resembles perceptual contrast. A discrimination between two parts also seems to increase the extent to which each part is apprehended as a separate group. Therefore, the conclusion accords with the position that two groups are associated with contrast, including for visibility.