Age-associated memory impairment—pathological memory decline or normal aging?

The aim of the study was to determine whether the memory capacity of individuals with age-associated memory impairment (AAMI) over a period of approximately 3½ years declines more, if at all, than the memory capacity of persons without AAMI. Four computerized and three non-computerized memory tests, a naming test, and a test of visuo-motor speed were administered twice. Two estimates of intellectual capacity were made, one at the first examination and the other 3½ years later. One person in the AAMI group (n=44) developed vascular dementia. The group of AAMI subjects did less well on two of the seven memory tests after 3½ years than they did initially; the control group (n=18) had lower scores on one memory test at follow-up than they had previously. The data suggest that the memory capacity of subjects with AAMI is not pathologically impaired. The general intellectual level significantly influences whether an individual with memory complaints will be classified AAMI or not. People with high intelligence are less likely than people with lower intellectual capacity to fulfill the AAMI criteria. This suggests that AAMI lacks in construct validity.     

Perceived rotary motion from changes in a straight line

The problem dealth with was how perception of a three-dimensional space is related to the corresponding two-dimensional retinal image. The stimulation used was a straight line changing length and direction. For this stimulation a geometrical model was developed. The basic decoding principle in this model is that the changes in the two-dimensional figure will be perceived as three-dimensional motions of an object with constant shape and size. This principle was approximately verified for the majority of the data. The main deviation from the model was that there was generally less perceived depth than predicted. Also a second decoding principle was generally verified: rotary, but not translator motion is perceived from this kind of stimulation. A third unexpected decoding principle was found in the data: the line is perceived in a frontal-parallel direction when it has its maximal extention.     

Effects of encoding strategy,presentation modality,and scoring method on STM performance with the Peterson and Peterson technique

The Peterson and Peterson (1959) STM experiment was replicated with variation of presentation modality and encoding strategy. The effect of various scoring criteria was also analyzed. The recall data showed that a Peterson and Peterson type forgetting curve was obtained using auditory presentation and instructions to rehearse vocally the trigrams when scoring only completely correct recall within the first 3 sec of the recall interval. With visual presentation and instructions to find meaningful trigram interpretations, the forgetting curve was higher and much more flat, especially when scoring position correct recall within the total 0-10-sec recall interval. In a buildup of PI experiment, no buildup of PI could be detected when visual presentation was used together with instructions to find meaningful trigram interpretations. The importance of the different encoding activities for recall performance was discussed.     

RECOVERY TIME AFTER GLARE: An experimental investigation of glare after-effect under night driving conditions

Preliminary experiments suggest that the changes in adaptation level due to glaring light in a night traffic meeting situation give no practically important deterioration of visibility. To obtain a more complete answer, one experiment was done in a 'real' night driving situation, and two experiments were carried out using a glare simulator, aimed at quantifying the change in the level of adaptation in terms of redetection time of a target made invisible due to glare. The effect of three factors were studied: duration of glare, maximum illuminance of glare, and contrast ratio between background and target. The preliminary suggestions were fully confirmed.     

Effects of a Daytime Nap on Primed and Repeated Remote Associates Tests and Relations with Divergent Creativity

The effect of napping versus wakefulness was studied on primed and repeated Remote Associate Tests (RATs) and on divergent creativity tests. The participants were 42 students from the USA, studying international courses at a Swedish university. The hypotheses for the RATs were (1), when the correct answers were primed before the nap, the RAT should be solved better for those who entered REM sleep, compared to those with no REM sleep or a resting condition; and (2), when retested the RAT should be solved better after a nap than after rest. For the creativity tests, hypothesis (3) was that creativity should be higher after the nap than after rest. Hypothesis 1 and hypothesis 3 were not supported. Hypothesis 2 was supported in an ANOVA. The REM group improved more than the rest group on the repeated RAT. Also, the No-REM and rest groups differed, strengthening the importance of both REM and No-REM sleep for creative problem-solving.