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Special Lecture 7

Social Buffering Dances with Stress

Lung Yu, Ph.D.

Distinguished Professor, National Cheng Kung University

The need to interact with others and obtain social buffering has driven much of the evolution of
human beings and the brains. Though not consensual in its definition, social buffering can be
regarded as the imagination, perception or actuality that one has assistance available from other
people. To date, many theorists and clinicians posit that social buffering can benefit for both physical
and mental health. Dated years back, I and my colleagues decided to study the biological substrates
of and the underlying mechanisms for mediating the social buffering in the central nervous system
by using a well-defined stress paradigm in mouse models. First, we established an acute, tandem
stressor procedure. We then found that such a stressor procedure decreased cell proliferation and
neurogenesis in the dentate gyrus, while these effects were abolished by the presence of companions
(or their odors-impregnated wood blocks). Second, such a companion-exerted buffering effect was
partially due to companions’ odors-increased secretion of BDNF in the local area. Third,
evolutionary proximity seemed to play an intriguing role in modulating the magnitude of the social
buffering effect. Fourth, social buffering effectively reversed the stressor-caused decreases in total
dendritic length and branch in the existing granule cells in the dentate gyrus. Fifth, sex differences in
dentate neurogenesis and social buffering were noticed in both young and old mice. Finally, social
buffering prevented the stressor-produced cognitive deficits in learning and memory.