ReviewMemory encoding and aging: A neurocognitive perspective
Section snippets
The roles of sensory impairments and age-related slowing
One factor that seems likely to affect the adequacy of memory encoding in older adults is the quality of sensory information presented to the cognitive system. Declines in both vision and hearing are well established in the elderly, and it seems probable that degraded sensory inputs will reduce the richness or specificity of the encoded record. One early study was conducted by Rabbitt (1968) who showed that when the stimulus representation was degraded by noise in young adults, subsequent
The problem of inadequate processing resources
From the perspective of a processing view of memory (Craik and Lockhart, 1972, Craik and Tulving, 1975), good subsequent memory performance depends on the depth and elaboration of the initial encoding processes. That is, perceived stimuli and events must be processed in terms of their meaning and significance; they should also be processed in a rich elaborate manner. Such extensive processing operations require adequate attentional resources, and these resources are available to young adults
Age-related changes in brain structure and function
Age-related changes in the neural underpinnings of cognitive processes are well documented and largely reflect deterioration from young adulthood (Raz, 2000, Raz et al., 2005). Changes include volumetric declines in hippocampus and frontal cortex, thinning of white matter tracts, reductions in dopamine production and receptors; these age-related changes are especially prominent in frontal cortex and some medial-temporal areas – regions intimately associated with memory encoding processes (
Encoding of nonverbal materials
Verbal materials, whether they are single words, sentences or text passages, are rather idiosyncratic in that it is possible to process them in a variety of ways, running from a superficial visual scan to a deeply integrative reading involving previous knowledge and inferential reasoning. These various ‘levels’ of processing have substantial effects on later memory for the material, but this variety of different types of processing is typically not available for other materials. We can perceive
Characteristics of encoding: binding and distinctiveness
In many cases, components of an event, utterance or statement must be bound together to form a coherent unit, which is then remembered as such. Laboratory examples include paired-associate learning (of unrelated word pairs), and everyday examples might include the necessity to remember the person you lent a book to, or the people present at a meeting. A particularly important aspect of this need to bind components together is ‘source memory’ – remembering where and when a specific event
Overcoming the deficit: environmental support
This review has largely been concerned with age-related losses in encoding efficiency, resulting in poorer later memory performance. There is also a substantial literature on compensatory mechanisms, however, at both behavioral and neural levels. One cognitive idea is that older adults are less able than their younger counterparts to self-initiate appropriate mental operations, owing perhaps to reduced attentional resources or to a decrease in frontally-based control mechanisms (Craik, 1983,
Encoding strategies and training studies
The observation that certain lifestyle factors promote cognitive reserve, coupled with research showing a preserved capacity for neuroplasticity and neurogenesis in later life, provides the basis for the idea that it may be possible to intervene and protect against age-related declines in memory. Various training approaches have been examined, but evidence for the utility, generalizability, and persistence of benefits from memory and cognitive training programs is mixed (for a review, see
Conclusions
In this review, we have discussed various cognitive and neurocognitive age-related changes that appear to underlie age differences in memory. Age-related declines in perception, processing speed, working memory and controlled attention – the ‘building blocks of encoding’ as it were – negatively affect the way in which events are encoded, with the apparent result that older adults have impoverished memory representations relative to their younger counterparts. In response to such processing
References (106)
- et al.
Aging gracefully: compensatory brain activity in high-performing older adults
NeuroImage
(2002) - et al.
Levels of processing: a framework for memory research
J. Verb. Learn. Verb. Behav.
(1972) - et al.
Deep processing activates the medial temporal lobe in young but not in old adults
Neurobiol. Aging
(2003) - et al.
Effects of memory training on cortical thickness in the elderly
NeuroImage
(2010) - et al.
Training-induced plasticity in older adults: effects of training on hemispheric asymmetry
Neurobiol. Aging
(2007) - et al.
Age-related changes in grey and white matter structure throughout adulthood
NeuroImage
(2010) - et al.
Working memory, comprehension, and aging: a review and a new view
- et al.
Cognitive aging and increased distractibility: costs and potential benefits
Remembering the data: analyzing interactive processes in reading
J. Verb. Learn. Verb. Behav.
(1983)A process dissociation framework: separating automatic from intentional uses of memory
J. Mem. Lang.
(1991)
Age differences in depth of retrieval: memory for foils
J. Mem. Lang.
Aging cognition: from neuromodulation to representation to cognition
Trends Cognit. Sci.
Under-recruitment and nonselective recruitment: dissociable neural mechanisms associated with aging
Neuron
Levels of processing versus transfer appropriate processing
J. Verb. Learn. Verb. Behav.
Working memory as a processing resource in cognitive aging
Dev. Rev.
Retrieval without recollection: an experimental analysis of source amnesia
J. Verb. Learn. Verb. Behav.
Episodic memory across the lifespan: the contributions of associative and strategic components
Neurosci. Biobehav. Rev.
The attentional demands of encoding and retrieval in younger and older adults: evidence from divided attention costs
Psychol. Aging
The effects of divided attention on encoding- and retrieval-related brain activity: a PET study of younger and older adults
J. Cogn. Neurosci.
Age-related cognitive deficits mediated by changes in the striatal dopamine system
Am. J. Psychiat.
Effects of cognitive training interventions with older adults: a randomized controlled trial
JAMA
Emergence of a powerful connection between sensory and cognitive functions across the adult life span: a new window to the study of cognitive aging
Psychol. Aging
Parallel effects of aging and time pressure on memory for source: evidence from the spacing effect
Mem. Cogn.
Training effects on dual-task performance: are there age-related differences in plasticity of attentional control?
Psychol. Aging
Who benefits from psychological training?
Psychol. Sci.
Frontal cortex contributes to human memory formation
Nat. Neurosci.
Hemispheric asymmetry reduction in older adults: the HAROLD model
Psychol. Aging
Task-independent and task-specific age effects on brain activity during working memory, visual attention and episodic retrieval
Cereb. Cortex
Functional neuroanatomy of recall and recognition: a PET study of episodic memory
J. Cogn. Neurosci.
Memory for grocery prices in younger and older adults: the role of schematic support
Psychol. Aging
Aging and memory for numerical information: the role of specificity and expertise in associative memory
J. Gerontol. B: Psychol.
Feature memory and binding in young and older adults
Mem. Cogn.
Age-related changes in object processing and contextual binding revealed using fMR adaptation
J. Cogn. Neurosci.
The magical mystery four: how is working memory capacity limited, and why?
Curr. Dir. Psychol. Sci.
On the transfer of information from temporary to permanent memory
Philos. Trans. Roy. Soc. Lond., Ser. B
A functional account of age differences in memory
Human memory and aging
Aging and cognitive deficits: the role of attentional resources
Elaboration and distinctiveness in episodic memory
Age differences in recall and recognition
J. Exp. Psychol. Learn.
Age-related differences in recognition memory: effects of materials and context change
Psychol. Aging
Age differences in memory: the roles of attention and depth of processing
Depth of processing and the retention of words in episodic memory
J. Exp. Psychol. Gen.
Hippocampal contributions to episodic encoding: insights from relational and item-based learning
J. Neurophysiol.
Que PASA? The posterior anterior shift in aging
Cereb. Cortex
Neuroimaging of healthy cognitive aging
Effects of aging on the neural correlates of successful item and source memory encoding
J. Exp. Psychol. Learn.
The relationship between aging, performance, and the neural correlates of successful memory encoding
Cereb. Cortex
Age-related reductions in human recognition memory due to impaired encoding
Science
The effects of age on the neural correlates of episodic memory
Cerebral Cortex
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