J. Doyne Farmer and John Geanakoplos (2009) - HYPERBOLIC DISCOUNTING IS RATIONAL: VALUING THE FAR FUTURE WITH UNCERTAIN DISCOUNT RATES, Cowles Foundation Discussion Paper No. 1719

Conventional economics supposes that agents value the present vs. the future using an exponential discounting function. In contrast, experiments with animals and humans suggest that agents are better described as hyperbolic discounters, whose discount function decays much more slowly at large times, as a power law. This is generally regarded as being time inconsistent or irrational. We show that when agents cannot be sure of their own future one-period discount rates, then hyperbolic discounting can become rational and exponential discounting irrational. This has important implications for environmental economics, as it implies a much larger weight for the far future.

Nir Jaimovich and Henry E. Siu (2007) - The Young, the Old, and the Restless: Demographics and Business Cycle Volatility, Federal Reserve Bank of Minneapolis Research Department Staff Report 387

We investigate the consequences of demographic change for business cycle analysis. We find that changes in the age composition of the labor force account for a significant fraction of the variation in business cycle volatility observed in the U.S. and other G7 economies. During the postwar period, these countries experienced dramatic demographic change, although details regarding extent and timing differ from place to place. Using panel-data methods, we exploit this variation to show that the age composition of the workforce has a large and statistically significant effect on cyclical volatility. We conclude by relating these findings to the recent decline in U.S. business cycle volatility. Using both simple accounting exercises and a quantitative general equilibrium model, we find that demographic change accounts for a significant part of this moderation.

An, Sungbae, Yongsung Chang, and Sun-Bin Kim. (2009) - "Can a Representative-Agent Model Represent a Heterogeneous-Agent Economy." American Economic Journal: Macroeconomics, 1(2): 29–54.

Accounting for observed fluctuations in aggregate employment, consumption, and real wage using the optimality conditions of a representative household requires preferences that are incompatible with economic priors. In order to reconcile theory with data, we construct a model with heterogeneous agents whose decisions are difficult to aggregate because of incomplete capital markets and the indivisible nature of labor supply. If we were to explain the model-generated aggregate time series using decisions of a stand-in household, such a household must have a nonconcave or unstable utility as is often found with the aggregate US data.

Heinz-Peter Spahn (2009) - The New Keynesian Microfoundation of Macroeconomics, Discussion Paper Univsersity of Hohenheim nr. 317/2009

New Keynesian Macroeconomics (NKM) obeys to the new dogma that macroeconomics should be
firmly grounded in First Principles of micro theory. Households are assumed to run an intertemporal
optimization calculus with respect to leisure and consumption by making use of perfect financial markets.
The supply side is organized so that full employment prevails. Macroeconomic coordination
problems between saving and investment are absent. In order to make model predictions more compatible
with empirical facts, NKM chooses "ad hoc" microfoundations: utility functions and market
structures are designed arbitrarily to allow for persistence of macro variables. NKM's reduced hybrid
macro model, with lags and expectational leads, is a useful "work horse", compatible with various micro
reasoning. However, NKM's insistence on the representative agent obstructs an understanding of
heterogeneous beliefs and learning.

There has been quite an amount of material on this in the contex of the unravelling financial crisis. The three links below are not exhaustive in themselves but should lead you to the most relevant contributions.

Free Exchange - Sometimes Economists Believe Strange Things

Econbrowser - The Failure of Macroeconomics?

Mark Thoma - The Unfortunate Uselessness of Most 'State of the Art' Academic Monetary Economics