Sensitivity to changes in size and velocity in young and elderly observers

Thresholds for detection of change of size and for detection of change of velocity were measured in young and elderly observers. No differences in thresholds between these subject groups were found at the fovea or in more peripheral retina. The results indicate a degree of functional redundancy in the peripheral retina of elderly subjects, even though there is evidence of reduced numbers of functional photoreceptors in the periphery.     

Repeated study of items with and without repeated context: aging effects on memory discriminability

Presenting items multiple times during encoding is a common way to enhance recognition accuracy. Under such conditions, older adults often show an increase in false recognition that counteracts benefits of repeated study. Using a false-memory paradigm with related study items and related lures, we tested whether repetition within the same encoding task or repetition across two different encoding tasks would be more beneficial to older adults’ memory discriminability. Results showed that, compared to items not repeated at study, items repeated in the same context and items repeated across different contexts showed improvements in memory discriminability in both young and older adults. This improvement was primarily reflected in improved recollection responses for both age groups across both repeat study conditions, as compared to no repetition. Importantly, the results demonstrated that repetition can be used to successfully mitigate age-related deficits by increasing memory discriminability and without incurring a cost of false recognition specific to any one age group.     

"I'm attached, and I'm a good guy/gal!": how character attachment influences pro- and anti-social motivations to play massively multiplayer online role-playing games

One's feelings of intimacy and connectedness with distal, fictional media characters are referred to as parasocial interactions. Video games have challenged this concept, as the distance between game players and characters is greatly reduced, if not completely removed, in virtual environments. Games encourage the internalization and psychological merging of a player's and a character's mind, a multidimensional concept known as character attachment (CA). Data from our study suggest that dimensions of CA are useful in understanding both pro- and anti-social gaming motivations. Pro-social gamers feel a greater sense of control over their characters, while anti-social gamers are more likely to suspend their disbelief of the game environment and not take responsibility for their virtual actions. Pro-social gaming was more prevalent in older gamers, and younger male game characters were motivated by anti-social reasons.     

The MMPI-2 With College Students

MMPI-2 responses of 515 male and 797 female college students from four universities were examined. College students were compared with the new MMPI-2 normative sample on the clinical and validity scales. The reliability of MMPI-2 scores of college students were compared with reliabilities of the MMPI-2 normative sample. The results indicated that college students respond to the MMPI-2 in a highly similar manner to the MMPI-2 normative sample. Mean score differences on the validity and clinical scales were within 1 to 3 T-score points on most scales, and the frequency distributions of the college students were highly similar to those of the MMPI-2 normative samples, Slight differences obtained on the Pt, Sc, and Ma scales may reflect the younger age of the college groups compared to the MMPI-2 normative groups. The MMPI-2 norms were shown to be appropriate for use with college subjects. Test-retest correlation coefficients obtained from college students who were administered the MMPI-2 on two occasions showed reliabilities comparable to those found for the MMPI-2 normative sample.     

Transverse patterning reveals a dissociation of simple and configural association learning abilities in rats with 192 IgG-saporin lesions of the nucleus basalis magnocellularis

This experiment tests the hypothesis that the cholinergic nucleus basalis magnocellularis (NBM) is necessary for complex or configural association learning, but not elemental or simple association learning. Male Long-Evans rats with bilateral 192 IgG-saporin lesions of the NBM (n = 12) and sham-operated controls (n = 8) were tested in the transverse patterning problem, which provides a test of both simple and configural association learning. Rats were trained in phases to concurrently solve first one, then two, and finally three different visual discriminations; Problem 1 (A+ vs B- sign) and Problem 2 (B+ vs C-) could be solved using simple associations, whereas solving Problem 3 (C+ vs A-) required the ability to form configural associations. Consistent with our hypothesis, the NBM lesion group solved the simple discriminations in Problems 1 and 2 but showed impaired configural association learning in Problem 3. Additionally, when Problem 2 was introduced, previously high levels of performance on Problem 1 suffered more in the NBM lesion group than in the control group; this finding suggests an impairment in the ability of animals with NBM lesions to divide attention among multiple stimuli or to shift between strategies for solving different problems. Results support our argument that the NBM is critically involved in the acquisition of associative problems requiring a configural solution but not in problems that can be solved using only simple associations. The observed impairments in configural association learning and the apparent loss of cognitive flexibility or capacity are interpreted as reflecting specific attentional impairments resulting from NBM damage.