Age Differences In Acquisition Research Articles

Word norms and measures of linguistic reclamation for LGBTQ+ slurs

Abstract While databases of taboo language word norms exist, none focus specifically on slurs as a category of taboo language. Furthermore, no existing databases include measures of linguistic reclamation, a phenomenon which may specifically affect the processing of slurs. I produced a database in which 155 native or near-native speakers of British English rated 41 LGBTQ+ slurs for a number of word properties and measures of linguistic reclamation. I then ran correlation and demographic group comparison analyses on the resulting database. I found a clear correlation pattern between properties and reclamation behaviours. I also found that there were age-related differences in age of acquisition and familiarity ratings; that gender identity and sexual identity differences were affected by being the target of slurs; and that sexual identity particularly affected differences in reclamation ratings.

Extinction and drug‐induced reinstatement of cocaine seeking following self‐administration or conditioned place preference in adolescent and adult rats

Adolescence marks a particularly vulnerable period to developing substance use disorders, and people who start using drugs in adolescence are more likely to relapse. A limited number of studies have investigated age difference in relapse following re-exposure to the drug after a period of abstinence. Using a cocaine self-administration paradigm, we showed no age difference in acquisition or extinction of self-administration. Interestingly, adolescent rats displayed impaired cocaine-primed reinstatement of cocaine seeking. Using the same dose as that self-administered in the first experiment, we then investigated age differences in acquisition and extinction of conditioned place preference, as well as locomotor sensitization. While there were no differences in locomotor activity or acquisition of preference, adolescents failed to extinguish their preference, even when the number of extinction sessions was doubled from what adults received. Taken together, these results suggest that while cocaine has similar rewarding and reinforcing effects regardless of age, adolescents may attribute stronger salience to the drug-associated context. In addition, re-exposure to cocaine itself may not be a strong relapse trigger in adolescence. Overall, these findings suggest that we should focus more on alleviating drug-context salience compared to re-exposure to substance in order to reduce relapse of drug seeking in adolescents.

What is the impact of age of second language acquisition on the production of consonants and vowels among childhood bilinguals?

This study investigated bilinguals’ ability to produce language-specific acoustic values for consonants and vowels that are highly similar across the two languages. To investigate this ability, we targeted early bilinguals who had acquired two languages before the age of 12 and continued to use both languages on a daily basis. These adult bilinguals were separated into two groups: simultaneous bilinguals (or nearly so) who acquired both languages by their third year, and sequential bilinguals who acquired their second language between the ages of 8 and 12 years. Their speech production was studied through an acoustic analysis of stop consonants (voice onset time) and vowels (formant structure). Despite the differences in age of acquisition, these bilinguals used both languages on a regular basis at work and at home and were very proficient in both languages. In contrast to other early bilinguals who undergo a change in language dominance from their first language to their second, the participants in this study maintained relatively balanced abilities in both languages. This study revealed that childhood bilinguals can maintain contrasts across their two languages, even for very similar phonemes.

Disease severity in siblings with cystic fibrosis.

Since cross-infection occurs between cystic fibrosis (CF) siblings, we hypothesized that subsequent siblings may acquire respiratory pathogens at an earlier age and have a more severe course of pulmonary disease. We studied a retrospective cohort of 31 sibling pairs from the CF database at the Hospital for Sick Children. Kaplan-Meier curves and modified log-rank tests were used to test sibling differences in age of acquisition of Pseudomonas aeruginosa (PA), Staphylococcus aureus (SA), or any positive culture. Differences in disease severity outcomes were explored. Older siblings were more likely to have both SA and any CF pathogen first isolated from respiratory culture at an older age than younger siblings (P = 0.0050 and P = 0.0008, respectively, by modified log-rank tests). However, more of the older siblings were positive on first culture at time of diagnosis, introducing an age-of-diagnosis bias. Hospitalization rates, courses of oral antibiotics, FEV(1) % predicted, and weight and height measurements were not better in the older children. No differences in clinical parameters were found between older and younger siblings. The apparent finding of younger age at first isolation of pathogens from respiratory cultures in younger siblings is likely because many older siblings were already infected with these organisms at time of diagnosis.

Visuospatial impairments in aged canines (Canis familiaris): The role of cognitive-behavioral flexibility.

This study used a novel delayed nonmatching-to-position task to compare visuospatial learning and memory in young and aged beagle dogs (Canis familiaris). The task used 3, rather than 2, spatial locations, which markedly increased difficulty. There were striking age differences in acquisition. Most of the aged canines did not learn the task, and those that did showed impaired learning when compared with the young canines. The aged canines also showed reduced maximal working memory capacity compared with the young canines. Analysis of the response patterns of individual canines indicated that the deficits were related to the use of ineffective strategies and inflexibility in strategy modification.

Visuospatial impairments in aged canines (Canis familiaris): The role of cognitive-behavioral flexibility.

This study used a novel delayed nonmatching-to-position task to compare visuospatial learning and memory in young and aged beagle dogs (Canis familiaris). The task used 3, rather than 2, spatial locations, which markedly increased difficulty. There were striking age differences in acquisition. Most of the aged canines did not learn the task, and those that did showed impaired learning when compared with the young canines. The aged canines also showed reduced maximal working memory capacity compared with the young canines. Analysis of the response patterns of individual canines indicated that the deficits were related to the use of ineffective strategies and inflexibility in strategy modification.

Rates of forgetting on three measures of verbal learning using retention intervals ranging from 20 min to 62 days

Previous research has examined age effects in rates of forgetting at short delay intervals of 20-30 min. The present study examined age effects in three verbal memory tasks at longer delay intervals of up to 62 days. Study participants consisted of 371 community-dwelling men and women comprising three age groups 20-39, 40-59, and 60-79 years. Age differences in acquisition and 20-min delayed recall were found on each of the memory tasks (paragraph, word list, and word pairs). However, all age groups showed equivalent rates of forgetting after this short delay interval. When participants were required to retain information for longer delay intervals (i.e., 1-62 days), increasing age was associated with faster rates of forgetting for day 1, but not over longer delay intervals. Age differences in rates of forgetting for longer delay intervals and the facilitating effects of prompted recall are discussed in terms of encoding and storage versus retrieval processes.

Neuroanatomical and cognitive correlates of adult age differences in acquisition of a perceptual-motor skill.

The objective of this study was to examine age differences in procedural learning and performance in conjunction with differential aging of central nervous system (CNS) structures. Sixty-eight healthy volunteers (age 22-80) performed a pursuit rotor task (four blocks of 20 15-second trials each). Volumes of the cerebellar hemispheres, neostriatum, prefrontal cortex, and hippocampus were measured from Magnetic Resonance (MR) images. Improvement in pursuit rotor performance was indexed by increase in time on target (TOT). A general improvement trend was evident across the blocks of trials. Overall, younger participants showed significantly longer TOT. The rate of improvement was age-invariant during the initial stages of skill acquisition but became greater in middle-aged participants as the practice progressed. When the influences of regional brain volumes were taken into account, the direct age effect on mean TOT measured during the first day of practice disappeared. Instead, reduced volumes of the cerebellar hemispheres and the putamen and poorer performance on nonverbal working memory tasks predicted shorter TOT. In contrast, neither the volume of the caudate and the hippocampus, nor verbal working memory showed association with motor performance. Pursuit rotor performance at the later stages of practice was unrelated to the reduction in putamen volume and was affected directly by age, cerebellar volume, and nonverbal working memory proficiency. We conclude that in a healthy population showing no clinical signs of extrapyramidal disease, age-related declines in procedural learning are associated with reduced volume of the cerebellar hemispheres and lower nonverbal working memory scores. During initial stages of skill acquisition, reduced volume of the putamen is also predictive of poorer performance.

A substituted pyrrolidinone, BMY 21502, and classical conditioning of the nictitating membrane response in young and older rabbits

New Zealand white rabbits (N = 76; 38 at 3 months, 38 at 21–55 months) were classically conditioned for 10 90-trial sessions in the 750-msec delay paradigm using a tone conditioned stimulus (CS) and corneal airpuff unconditioned stimulus (US). Young and older rabbits were divided into groups receiving paired CS-US presentations with 0, 5, or 10 mg/kg of BMY 21502. Unpaired tone and airpuff presentations were given to control groups administered 0 or 5 mg/kg of BMY 21502. Over training sessions, the older BMY-21502-treated rabbits produced a higher percentage of conditioned responses (CRs) and greater CR amplitude than did the vehicle-treated older rabbits. BMY 21502 did not facilitate conditioning in the young rabbits. There were significant age differences in acquisition between the young and older vehicle-treated animals. Although the BMY-21502-treated older rabbits did not achieve the asymptotic level of performance of the young rabbits, BMY 21502 treatment resulted in conditioning for the older rabbits that was similar to that for the younger rabbits.

Delay classical conditioning in young and older rabbits: initial acquisition and retention at 12 and 18 months.

Classical conditioning of the nictitating membrane-eyeblink response in young (7 months old) and older (36 months old) New Zealand white rabbits in a delay paradigm with a 400-ms conditioned stimulus-unconditioned stimulus interval was examined for initial acquisition and retention. Older animals required significantly more acquisition trials to reach learning criterion. Age differences in acquisition were temporary. Older rabbits responded at a level comparable to that of young rabbits such that total performance over the 630 trials of acquisition was not different. Rabbits in the explicitly unpaired control groups exhibited no age differences in unconditioned response amplitude or latency measures. Twelve- and 18-month retests demonstrated no significant age effects on retention. Patterns of retention differed between the age groups. Older rabbits required fewer trials to obtain the learning criterion at each phase of testing. Younger rabbits maintained a stable performance throughout training.

Adult age differences in acquisition and retention of frequency-of-occurrence information for actions

Adult age differences in frequency-of-occurrence memory for actions performed zero, one, or two times in the laboratory were investigated shortly after the actions had been performed and after a retention interval of 24 h. A moderate age difference in accuracy of frequency judgments was found on the immediate retention test. Forgetting over 24 h was moderate for both young adult and elderly adult subjects. A negligible interaction between age and retention interval suggested comparable forgetting rates for young and elderly subjects, at least over 24 h.

Temporal memory and content memory for actions: Adult age differences in acquisition and retention

Young adult and elderly adult subjects were tested under incidental memory conditions for recognition memory of content and temporal memory for the order of a series of actions performed in the laboratory. The tests were conducted both shortly after completion of the series and 24 hours later, with different sets of actions tested on each occasion. Recognition memory of content showed no forgetting for the young subjects, but significant forgetting for the elderly subjects. Memory for temporal information was substantially greater for the young subjects than for the elderly subjects. Both age groups showed substantial forgetting of temporal information over the 24-hour retention interval.

Age differences in acquisition and retention of one-way avoidance learning in C57BL/6NNia and autoimmune mice

Acquisition and 48-h retention of a step-up active avoidance response were studied in separate age groups of C57BL/6NNia mice (aged 1.5, 3.5, 6, 12, or 26 months) and five strains of genetically autoimmune mice differing in life span. The C57BL/6NNia mice showed no change in ability to acquire the avoidance response between 1.5 and 3.5 months, but showed a steady decline in that ability thereafter. Mouse strains with early-onset autoimmune disorder (NZB/B1NJ, MRL/MpJ-lpr, and BXSB/MpJ) showed declines in acquisition capability between 1.5 and 3.5 months of age, whereas mouse strains with mild, late-onset autoimmune disorder (MRL/MpJ- + and NZBWF1/J) showed stable or improved acquisition during that period. Both the C57BL/6NNia and NZB/B1NJ mice showed age-dependent declines in 48-h retention performance by 12 months of age. These findings suggested that while 48-h retention performance deficits were most related to chronological age, avoidance acquisition deficits were related to development of autoimmunity.

Children's Articulation Development: Some Regional Differences

The age of acquisition of consonant sounds by children aged two to nine years was determined by testing 1,375 children in the New England Region of New South Wales. Results were compared to data from previous Australian and American studies of articulation development, and indicated marked differences in age of acquisition of sounds. In addition, the testing of younger children was validated and the criterion previously used to measure sound acquisition examined.

Stimulus generalization of lifted weights in older and younger women.

Older (62 to 86 years) and younger (17 to 30 years) women were essentially similar in acquisition of weight discriminations and in generalized responding to a range of weights during postdiscrimination tests. In both age groups, acquisition was facilitated by increases in the difference between the positive and negative stimuli, and postdiscrimination gradients were displaced away from the value of the negative stimulus, particularly when it was the heavier of the training pair. The finding from personality test scores that the older women were more introverted than the younger ones, together with the absence of age differences in acquisition and generalization, does not support the Eysenck-Gray hypothesis that introversion influences conditioning processes. The results do suggest that basic conditioning processes are maintained with increasing age in healthy older adults.

The acquisition of basic sex information

Abstract Previously unpublished data from the Kinsey sample concerning the acquisition of basic sex information are presented. These are contrasted to data obtained from a similar, but smaller sample of respondents from the current generation. Basic facts about sex are being learned at considerably younger ages today, apparently as a result of increased maternal effort to provide information, increased sex education in the schools, and more explicit treatment of sex in the media. Same‐sex peers remain the dominant educators, but other sources, notably mothers, have increased in importance. The sex differences in age of acquisition found in the Kinsey sample have largely disappeared.