Article

Functional neuroimaging of self-referential encoding with age

Department of Psychology, Brandeis University, Waltham, MA 02454-9110, USA.
Neuropsychologia (Impact Factor: 3.45). 09/2009; 48(1):211-9. DOI: 10.1016/j.neuropsychologia.2009.09.006
Source: PubMed

ABSTRACT Aging impacts memory formation and the engagement of frontal and medial temporal regions. However, much of the research to date has focused on the encoding of neutral verbal and visual information. The present fMRI study investigated age differences in a social encoding task while participants made judgments about the self or another person. Although previous studies identified an intact self-reference effect with age, subserved by robust engagement of medial prefrontal cortex (mPFC) by both young and older adults, we identified a number of age differences. In regions including superior mPFC, inferior prefrontal cortex, and anterior and posterior cingulate cortex, young and older adults exhibited reversals in the pattern of activity for self and other conditions. Whereas young primarily evidenced subsequent forgetting effects in the self-reference condition, older adults demonstrated subsequent memory effects in the other-reference condition. These results indicate fundamental differences across the age groups in the engagement of elaborative encoding processes. We suggest that older adults may encode information about the self in a more normative manner, whereas young adults focus on encoding the unique aspects of the self and distinguishing the self from others.

Download full-text

Full-text

Available from: Daniel L Schacter, Feb 06, 2014
0 Followers
 · 
101 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Self-referential processing relies mainly on the medial prefrontal cortex (MPFC) and enhances memory encoding (i.e., Self-Reference Effect, SRE) as it improves the accuracy and richness of remembering in both young and older adults. However, studies on age-related changes in the neural correlates of the SRE on the subjective (i.e., autonoetic consciousness) and the objective (i.e., source memory) qualitative features of episodic memory are lacking. In the present fMRI study, we compared the effects of a self-related (semantic autobiographical memory task) and a non self-related (general semantic memory task) encoding condition on subsequent episodic memory retrieval. We investigated encoding-related activity during each condition in two groups of 19 younger and 16 older adults. Behaviorally, the SRE improved subjective memory performance in both groups but objective memory only in young adults. At the neural level, a direct comparison between self-related and non self-related conditions revealed that SRE mainly activated the cortical midline system, especially the MPFC, in both groups. Additionally, in older adults and regardless of the condition, greater activity was found in a fronto-parietal network. Overall, correlations were noted between source memory performance and activity in the MPFC (irrespective of age) and visual areas (mediated by age). Thus, the present findings expand evidence of the role of the MPFC in self-referential processing in the context of source memory benefit in both young and older adults using incidental encoding via semantic autobiographical memory. However, our finding suggests that its role is less effective in aging.
    Frontiers in Behavioral Neuroscience 01/2015; DOI:10.3389/fnbeh.2014.00449 · 4.16 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Self-reference effect (SRE) on long-term episodic memory and autonoetic consciousness has been investigated in normal young adults, scarcely in old adults, but never in Alzheimer’s patients. Is the functional influence of Self-reference still present when the individual’s memory and identity are impaired? We investigated this issue in 60 young subjects, 41 elderly subjects, and 28 patients with Alzheimer’s disease, by using 1) an incidental-learning task of personality traits in three encoding conditions, inducing variable degrees of depth of processing and personal involvement, 2) a 2-minutes retention interval free recall task, and 3) a 20-minutes retention interval recognition task, combined with a remember-know paradigm. Each score recorded was corrected for errors (intrusions in free recall, false alarms in recognition, and false source memory in remember responses). The Self-reference, compared with alternative encodings, significantly enhanced performance on the free recall task in the young group, and on the recognition task both in the young and elder groups but not in the Alzheimer group. The most important finding is that the Self-reference led more often to a subjective sense of remembering with the retrieval of the correct encoding source in the Alzheimer group. This Self-reference recollection effect in patients was related to independent subjective measures of a positive and definite sense of Self (measured by the Tennessee Self Concept Scale), and to memory complaints in daily life. In conclusion, these results demonstrated the power and robustness of the Self-reference effect on the recollection in long-term episodic memory in Alzheimer’s disease albeit the retrieval is considerably reduced. These results should open new perspectives for the development of rehabilitation programs for memory deficits.
    Current Alzheimer research 01/2014; 10(10):1107-1117. DOI:10.2174/15672050113106660175 · 3.80 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the contribution of cortical midline regions to stereotype threat and resiliency, we compared age groups in an event-related functional MRI study. During scanning, 17 younger and 16 older adults judged whether words stereotypical of aging and control words described them. Judging stereotype words versus control words revealed higher activations in posterior midline regions associated with self-referencing, including the precuneus, for older adults compared to younger adults. While heightening salience of stereotypes can evoke a threat response, detrimentally affecting performance, invoking stereotypes can also lead to a phenomenon called resilience, where older adults use those stereotypes to create downward social-comparisons to "other" older adults and elevate their own self-perception. In an exploration of brain regions underlying stereotype threat responses as well as resilience responses, we found significant activation in older adults for threat over resilient responses in posterior midline regions including the precuneus, associated with self-reflective thought, and parahippocampal gyrus, implicated in autobiographical memory. These findings have implications for understanding how aging stereotypes may affect the engagement of regions associated with contextual and social processing of self-relevant information, indicating ways in which stereotype threat can affect the engagement of neural resources with age.
    Frontiers in Human Neuroscience 09/2013; 7:537. DOI:10.3389/fnhum.2013.00537 · 2.90 Impact Factor