Decision Making Under Uncertainty: Differentiating Between 'If', 'What' and 'When' Outcomes Occur

  • Marianna Blackburn

    Student thesis: Phd


    Why is it difficult to save for a pension or maintain a healthy diet? Choosing between options that have future or delayed consequences presents a challenge for a decision maker. When faced with such intertemporal choices the tendency to favour choices with immediate or short term outcomes, otherwise known as delay discounting, can lead to suboptimal consequences in the long-term. However, the mechanisms underlying the devaluation of future outcomes are poorly understood. This is due to the lack of a consistent framework for the representation of delays and delayed outcomes. One perspective is to represent delays as uncertainty. However, current conceptions of uncertainty are limited, by and large, to the dimension of probability, and are therefore inadequate. This thesis adopts a delay discounting model and emphasises different types of uncertainties within choice. Unifying these components, a framework that considers intertemporal choice as decision making under uncertainty is proposed.A series of behavioural and electrophysiological studies is presented to demonstrate that: it is the perceived uncertainty about 'if' and 'when' outcomes occur that contributes to behavioural discounting (chapters 2 and 3); the perception and evaluation of 'what' is delayed is underlined by emotional processes (chapter 4); and that generally, uncertainties about 'if' and 'what' outcomes differentially characterise risky and impulsive choices (chapter 5), and can be distinguished in terms of their informational qualities (chapter 6). Collectively, these findings present a deconstruction of uncertainty into components of 'if', 'what' and 'when', that could be mapped to delayed outcomes. I discuss them within the context of judgement and decision making, individual differences, and neural aspects of reward processing. These results allow me to argue that 1) all decision making is a process of information availability; 2) behaviour is motivated to reduce uncertainty; 3) choice is the manifestation of acquired information gathered from a decision-maker's internal and/or external environment. In conclusion, this thesis demonstrates that decision making under uncertainty can be qualified beyond a single dimension of probability; and that uncertainty can be characterised as a state of incomplete information about 'if' what' and 'when' outcomes will occur. Accordingly, intertemporal and risky choices can be accommodated within a single framework, subject to the same cognitive and neural processes. Consequently, this framework allows for the design of behavioural interventions that specifically target reducing uncertainties of 'if', 'what' or 'when'.
    Date of Award1 Aug 2012
    Original languageEnglish
    Awarding Institution
    • The University of Manchester
    SupervisorWael El-Deredy (Supervisor)


    • Delay Discounting
    • Uncertainty
    • Decision-Making
    • Intertemporal Choice

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