Induced nostalgia increases optimism (via social-connectedness and self-esteem) among individuals high, but not low, in trait nostalgia

•Induced nostalgia increases optimism.•Induced nostalgia raises optimism by lifting social connectedness and self-esteem.•This causal sequence is obtained among persons high, but not low, in trait nostalgia.

Nostalgia, a sentimental longing for the past, is not merely a past-oriented emotion, but has implications for the future. Experimentally induced nostalgia fosters optimism by increasing social-connectedness (a sense of acceptance and belongingness) and self-esteem. Do these effects depend on trait nostalgia (i.e., proneness to nostalgic engagement)? Consistent with past research, induced nostalgia fostered optimism, and this effect was mediated by social-connectedness and self-esteem. More important, these effects uniquely applied to participants who were high, but not low, on trait nostalgia. That is, induced nostalgia (vs. control) was indirectly linked to heightened optimism through social-connectedness and self-esteem, for nostalgia prone individuals. Proneness to nostalgic engagement, when coupled with momentary nostalgia, confers benefits, not only in terms of greater social-connectedness and self-esteem, but also in terms of higher optimism.