Young and older adults (elderly in Experiment 1 and middle-aged in Experiment 2) received successive sentence recall tasks for which one-half of the sentences were read in a male voice and one-half in a female voice. With regard to the sex of voice component, the first task was administered under incidental learning conditions and the second under intentional learning conditions. With regard to sentence content, both tasks were administered under intentional learning conditions. The results indicated that encoding voice information is a cognitively effortful, age sensitive process. For older adults, both elderly and middle-aged, enhanced voice encoding under the intentional condition, relative to the incidental condition, was accompanied by a significant decrement in sentence recall. For young adults, the trade off effect was not large enough to reach statistical significance. The age difference apparently reflects the diminished processing capacity of older adults relative to young adults, with the decrease in capacity having its onset by middle age.

Near-IR FT-Raman spectra of B12 imidazole derivatives and cobalamins in aqueous solution were compared since there is now strong evidence that, in human B12-dependent enzymes, the 5,6-dimethylbenzimidazole (DMBz) is replaced by imidazole from a histidine in the protein. Derivatives studied include methylcobalamin [MeCbl (DMBz base-on) and MeCbl+ (base-off by acidification to protonate the DMBz)], methylaquacobinamide (MeCbi+) [Cbi's have the DMBz-bearing nucleotide loop removed by hydrolysis], and Me(N-acetylhistidine)Cbi [coordinated through imidazole in Me(N-AcHis)Cbi at pH 10 and imidazolate in Me(N-AcHis)Cbi- in 1 M NaOH]. Several marker bands changed with changes in the axial ligand trans to the methyl group. The frequency of the Co−CH3 stretching mode at ∼505 cm-1 (assigned by isotopic shift using −CD3) was similar for all MeCbl and MeCbi species; thus, the trans ligand, including the very powerful electron-donating imidazolate species, has little effect on Co−C bond strength. In contrast, the peak height of the Co−CH3 band, relative to the corrin long-axis mode band at 1495 cm-1, consistently increased 2-fold upon coordination of an N-donor ligand to MeCbi+ and MeCbl+. This intensity change appears to be a useful means of assessing ligand replacement reactions. With increasing trans ligand donor ability, the frequency of the corrin in-phase double-bond stretching mode along the short axis at ∼1545 cm-1 increased, but the frequencies of the corresponding long-axis mode at ∼1495 cm-1 and the corrin band at ∼1570 cm-1 were unchanged. The frequency of a corrin band at ∼1600 cm-1 increased slightly to 1603 cm-1 from the base-on to the base-off MeCbl form; the band is also at 1603 cm-1 for MeCbi+, Me(N-AcHis)Cbi, and Me(N-AcHis)Cbi-. A decrease in the frequency of the ∼1570 cm-1 band coincident with acid-catalyzed H-to-D exchange at the corrin C10 in acidic D2O solutions (confirmed by 1H NMR spectroscopy) was evidence that it is a corrin band. However, the frequency and intensity of this band were relatively insensitive to the trans ligand. This diverse dependence of the corrin-band frequencies on changes in trans axial ligand bulk suggests that in these B12 derivatives there are no large structural distortions. Differences in electron donation by the trans ligands have the greater influence on the spectra. A band at ∼1315 cm-1 was found to be characteristic of unprotonated DMBz; it is absent when DMBz is removed (Cbi's) or protonated (MeCbl+) but present in all other Cbl's, including base-off (CN)2Cbl-. An ∼30 cm-1 shift to lower frequency of the overlapping amide I bands of cobalt corrinoids between H2O and D2O was caused by amide NH2 to ND2 exchange. The frequency shift of ∼10 cm-1 of this band between H2O and ethanol was consistent with a small redistribution of resonance forms of the amide group between solvents. Since the band for the CD3 symmetric stretch of the Co−CD3 group lies in a region of the spectrum (∼2105 cm-1) that is devoid of other bands, it may be useful in studies of enzyme-bound Me-d 3-Cbl...

This paper reports the findings of two studies on everyday memory in young adulthood. In Study 1, 387 male and female college students (18-22 years old) completed the 25-item Cognitive Failures Questionnaire (CFQ; Broadbent, Cooper, Fitzgerald & Parkes, 1982). Principal components analysis yielded five internally consistent factors: distractibility; misdirected actions; spatial/kinaesthetic memory; interpersonal intelligence; and memory for names. Further, each of these dimensions was interpretable within an information-processing framework. Study 2 examined the relation of the five everyday memory dimensions obtained in Study 1 to measures of working memory and traditional intelligence in a separate sample of 32 college students. Findings obtained in Study 2 suggest that attentional processes may be important components of the everyday memory construct.

Divergent thinking was assessed in 400 adult women and men with tests of word association (associational ‘ uency) and alternate uses (production ‘ uency, ‘ exibility, and originality). The participants were from four age cohorts: young (17-22 years old), middle-aged (40-50), young-old (60-70), and old-old (75+). The test battery also included two intellectual “process” variables (inductive reasoning, memory span), one “dynamic resource variable” (intellectual speediness), one “structural resource variable” (vocabulary), and two moderator variables (depression, education). Hierarchical multiple regression analyses showed that divergent thinking was significantly, linearly, positively, and moderately related to all of these variables except depression, which was not significantly related to divergent thinking. Effects of age group and gender were assessed in analyses of variance (alpha = .01). The age groups did not differ significantly in associational ‘ uency, but the middle-aged group was the best on production ‘ uency, ‘ exibility, and originality. Gender had a significant effect on only one variable: Women had higher depression scores than men.