Localized intracaudate dopamine D2 receptor activation during the post-training period improves memory for visual or olfactory conditioned emotional responses in rats.

Rats with cannulas aimed at the posteroventral (PV) or ventrolateral (VL) areas of the caudate nucleus were trained on a conditioned emotional response (CER) task. Post-training microinjections of the indirect catecholamine agonist, d-amphetamine (5 micrograms), or of the dopamine D2 receptor agonist, LY171555 (1 microgram), into the PV area improved retention of a CER with a visual CS, but had no effect on a CER with an olfactory CS. Post-training injections of the same two drugs into the VL area improved retention of a CER with an olfactory CS, but had no effect on a CER with a visual CS. Post-training injections of the dopamine D1 receptor agonist, SKF38393 (0.5, 1.0, 2.0 micrograms), into either site had no effects on either CER. These findings suggest that different areas of the caudate nucleus mediate acquisition of CERs with different CSs, possibly implicating the topographically organized corticostriatal innervation in the acquisition of certain types of memories in the caudate nucleus. The findings also suggest that dopamine D2 receptors in the caudate nucleus are involved in the acquisition of these CERs.     

Fuel for Thought? A Systematic Review of Neuroimaging Studies into Glucose Enhancement of Cognitive Performance

Neuropsychology Review - A transient improvement in cognitive performance can be observed following the ingestion of a glucose drink, a phenomenon known as the ‘glucose facilitation...     

Exploring Wellbeing in Youth with Vision Impairment: Insights for Vision Rehabilitation

Applied Research in Quality of Life - This article explores the discussions of 21 young Australians (aged 12–25) with vision impairment regarding their lived experiences and what it meant for...     

Extinction revisited: similarities between extinction and reductions in US intensity in classical conditioning of the rabbit's nictitating membrane response

The mechanisms of extinction were examined by reducing the intensity of the unconditioned stimulus (US) after acquisition training to determine whether such reductions lie on a continuum with CS-alone extinction. The experiments revealed that reductions in US intensity yielded extinction-like effects. Specifically, there were proportional reductions in the daily mean level of responding across sessions. There were also persistent within-session declines and between-session increases of responding analogous to spontaneous recovery. Surprisingly, even when US intensity was held constant, within-session declines and between-session increases were apparent. The results are discussed with respect to possible contributions from unlearning, new learning, generalization decrement, and nonassociative loss, especially CS-specific attentional changes and CR-specific reactive inhibition.     

The boogie-woogie illusion

A grid of vertical and horizontal lines, each composed of light and dark squares, is moved rigidly at 45 degrees to the vertical on a gray surround. When the luminance of the background is set midway between the luminances of the light and dark squares, the squares appear to race along the lines even though they are actually 'painted' on the lines. The effect arises from the unequal apparent speeds of the lines and their textures. The light and dark squares along the lines define a first-order pattern whose apparent speed, parallel or along the line, is close to veridical. The lines themselves have no overall luminance difference from the background so that they are defined by a second-order difference. As reported elsewhere, apparent speed is reduced for second-order motion so that the motion perpendicular to the line is perceived as slower than the motion along the line even though they are physically equal. The imbalance creates the impression that the small squares are moving along the lines rather than moving rigidly with them.     

Does priming specific syllables during tip-of-the-tongue states facilitate word retrieval in older adults?

This experiment investigated whether phonological priming of syllables helps resolve tip-of-the-tongue (TOT) states in young and older adults. Young, young-old, and old-old adults read general knowledge questions and responded "know," "TOT," or "don't know" accordingly. Participants then read a list of 10 words that included 3 phonological primes corresponding solely to the first, middle, or last syllable of the target word. Young and young-old adults resolved more TOTs after first-syllable primes, but old-old adults showed no increase in TOT resolution following any primes. These results indicate that presentation of the first syllable of a missing word strengthens the weakened phonological connections that cause TOTs and increases word retrieval, but not for old-old adults who experience greater deficits in the transmission of priming across these connections.     

Odorant quality perception: a metric individual differences approach

Perceptual spaces, in which similar stimuli are located close to each other and dissimilar stimuli are located far apart, have aided in the understanding of the physiological and psychological bases for sensory quality coding. Differences in perception between individuals should be reflected by differences in the spatial relationships between stimuli. If the dimensionality of the perceptual space is small (e.g., color space), individual differences that reflect specific pathologies are readily apparent from visual inspection. On the other hand, if the dimensionality of the perceptual space is large (as is proposed for odor space), visual inspection alone may not reveal individual differences in quality perception. The present work presents an information-theory-based method for quantifying individual differences in quality perception from perceptual confusion matrices. The ability of this method to quantify individual differences in quality perception is shown in a hypothetical example of specific anosmia. Finally, the method is applied to the examination of intrasubject consistency of odorant quality perception.     

Effects of Stimulant Medication Treatment on Mothers' and Children's Attributions for the Behavior of Children with Attention Deficit Hyperactivity Disorder

Participants were 55 children with attention deficit hyperactivity disorder (ADHD) who were receiving ongoing treatment with stimulant medications and their mothers, and 31 children with ADHD who were beginning stimulant medication and their mothers. Mothers and children offered attributions for child behaviors that occurred when the child was medicated and not medicated. Mothers rated child compliance and prosocial behavior as more global and stable when the child was medicated and rated noncompliance, ADHD symptoms, and oppositional behavior as more externally caused, less global and stable, but more controllable by the child when the child was medicated. Children rated both their compliance and noncompliance as more controllable in the medicated condition. On a forced-choice measure, both mothers and children selected ability, effort, and task attributions for compliance more in the not-medicated condition, and pill-taking attributions more in the medicated condition. This was reversed for noncompliance, which was attributed more to effort, task, or ability in the medicated condition and more to not taking a pill in the not-medicated condition. The potential risks and benefits for parent–child interactions and children's self-perceptions of these medication-related differences in attributions are discussed.