Homeworks academic service


The effect of age on short term

The use, distribution and reproduction in other forums is permitted, provided the original author s or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. This article has been cited by other articles in PMC. Abstract Prior research suggests that acoustical degradation impacts encoding of items into memory, especially in elderly subjects.

We here aimed to investigate whether acoustically degraded items that are initially encoded into memory are more prone to forgetting as a function of age. Young and old participants were tested with a vocoded and unvocoded serial list learning task involving immediate and delayed free recall.

Effects of age, gender, and stimulus presentation period on visual short-term memory.

We found that degraded auditory input increased forgetting of previously encoded items, especially in older participants. We further found that working memory capacity predicted forgetting of degraded information in young participants.

In old participants, verbal IQ was the most important predictor for forgetting acoustically degraded information. Our data provide evidence that acoustically degraded information, even if encoded, is especially vulnerable to forgetting in old age. Many everyday situations are however characterized by factors that impact acoustic richness such as competing speakers, increased background noise or subject-specific factors like age-associated hearing loss, even if compensated with hearing aids.

Despite this reduction in acoustic richness, listeners are usually able to extract information from degraded speech signals Davis et al. Speech comprehension is however slower and less efficient in these situations e. Several lines of evidence further suggest that acoustic degradation may impact memory because degradation draws on resources that are no longer available for encoding of items into memory.

For example, it has been shown that immediate recall and associative memory decline the effect of age on short term young adults presented with experimentally degraded stimuli.

The performance decline mimics the performance of older adults with age-related hearing loss—even if the stimuli are presented with enough clarity to be understood McCoy et al.

Supplemental Content

As expected, poor hearing status increased dual task costs on immediate recall, an effect that was exacerbated in elderly subjects. Several recent neuroimaging studies provide evidence for the neural consequences of degraded auditory input.

They compellingly demonstrate that even a mild to moderate hearing impairment leads to an impoverished representation of auditory input in speech processing regions such as the superior temporal the effect of age on short term and reduced structural integrity of primary auditory cortex Peelle et al.

Moreover, studies in young and elderly volunteers with age-appropriate hearing provide further evidence that the processing of degraded auditory input co-occurs with increased activation in a cingula-opercular network and this compensatory activation in non-speech areas is related to increased speech recognition Wild et al. Aging impacts both, auditory processing, especially in challenging situations, and cognitive function such as working and long term memory.

For example, hearing-impaired elderly subjects show stronger impairments in understanding linguistically complex sentences than younger subjects with the same hearing impairment Wingfield et al. Additional evidence supports the interaction between the loss of acoustic detail and verbal memory because memory in older adults was found to be stronger affected by acoustic degradation Heinrich and Schneider, 2011.

The relation between cognitive and sensory decline in old age has been investigated extensively e. That working memory the effect of age on short term also play a causal role in long term memory decline was recently shown by Hara and Naveh-Benjamin 2015who manipulated working memory in young healthy volunteers and were able to reproduce the associative memory deficit observed in old age.

We here aimed to investigate to what extent degraded auditory input impacts on consolidation of information into long term memory. In addition, we aimed to explore in the current dataset, how these effects are related to working memory capacity. While the research reviewed above suggests that degraded auditory information impacts initial encoding, it is not known whether degraded information, that is initially encoded, undergoes consolidation to the same extent as non-degraded information or whether degraded information is more fragile and prone to forgetting.

We choose for an experimental degradation of auditory input rather than the natural degradation present in age-related hearing loss since the comparison of hearing impaired subjects with a control population is often confounded by age given that hearing impairments get more prevalent with increasing age.

Introduction

the effect of age on short term We presented young and old participants with a vocoded and unvocoded version of a standardized verbal list learning task that had to be recalled immediately on successive trials as well as after a 30 min delay. Forgetting was gauged by comparing immediate and delayed recall. We hypothesized that vocoded information should be more vulnerable to forgetting and that the effect should increase in old age. Further, we hypothesized that a higher working memory capacity may counteract forgetting of vocoded information given prior evidence that individual differences in forgetting in elderly volunteers are strongly related to working memory capacity and processing speed Zimprich and Kurtz, 2013.

Materials and Methods Subjects Twenty-one younger 18—34; mean: All participants were right-handed, native speakers of German and had an above average verbal IQ as tested with a multiple choice word test that requires participants to select the correct word among five distractor non-words and hence tests for vocabulary size WST, Schmidt and Metzler, 1992.

All subjects had age appropriate hearing which was defined as less than 20 dB HL between 125 Hz and 8 kHz in young participants and less than 25 dB HL for individual frequencies below 3 kHz as well as less than 20 dB HL combined over the frequencies of 500 Hz, 1 kHz, 2 kHz and 4 kHz in old participants. Participants with any significant neurological or psychiatric conditions were excluded. Ethics approval was obtained from the local ethics committee.

The study was conducted in accordance with the Declaration of Helsinki, and all procedures were carried out with the adequate understanding and written informed consent of all participants. Four subjects in the older group and one subject in the younger group had to be excluded from the analysis for the following reasons: Procedure and Tests Participants took part in two testing sessions of 90 min each on two subsequent days.

All testing was conducted in a double walled sound attenuating booth. This was followed by the presentation and immediate free recall of a second 15-word list list B, B1 and the subsequent requirement to recall list A again A6 after this interference. Memory was assessed after a 30 min break with free recall of list A A7 and a following recognition test A8.

The recognition test consisted of 50 verbally presented words, the 15 target words from list A, 15 distractor words from list B and 20 new words.

To the effect of age on short term the effects of degraded auditory input on verbal learning and memory, we used two parallel versions of the VLMT.

Both versions were spoken by a female speaker, recorded and vocoded as detailed below. During testing, participants listened to the vocoded and unvocoded audiofiles via headphones. In the vocoded condition, only words that matched the correct word were scored as correct. This measure was chosen as primary outcome rather than the immediate or delayed recall per se, because it is not confounded by the number of words understood by each individual participant.

The measure therefore enables a comparison between the vocoded and unvocoded condition even with reduced performance under vocoded speech conditions. Note that the performance in B1 and A6, which are part of this standardized test, can be used to measure memory after interference. Since this was however not the focus of the present study this data were not analyzed.