Browsing by Subject "Working Memory"

Working memory—the mental capacity to “hold on to” information after it ceases to be perceptually available—is one of the most discussed topics in psychology and neuroscience. Despite the importance of working memory in the sciences, however, there is only a small amount of philosophical research on the topic. The aim of my dissertation is to provide a philosophically-informed account of working memory, and to assess its relationship to other mental phenomena, including attention and consciousness.

In chapter one, I provide a broad historical overview of working memory. I begin by outlining William James’ original distinction between “primary” and “secondary” memory, and work my way up to present-day neuroscientific investigations of working memory. One of the main conclusions of this chapter is that there is no single working memory “module” in the brain. Instead, working memory is best conceptualized as a functionally-defined process that is potentially realized by multiple neural mechanisms.

In chapter two, I explore the link between working memory and attention. Recent evidence from psychology and neuroscience indicates that attention is (to some extent) involved in the process of working memory maintenance. However, it remains unclear whether the contents of working memory are always attended, or if working memory representations can be dynamically shifted in and out of the focus of attention. Drawing on empirical and phenomenological data, I argue that the second view is correct. Although attention plays an important role in working memory maintenance, working memory representations can persist—at least temporarily—outside the focus of attention.

Chapter three addresses a related question: namely, how working memory relates to consciousness. I distinguish three possible positions on this score: (i) working memory representations are always conscious; (ii) working memory representations can be either conscious or unconscious, but they are all accessible to consciousness; and (iii) working memory representations can be either conscious or unconscious, and some are inaccessible to consciousness. Based on the available empirical data, I argue in favor of position (ii). Evidence suggests that working memory representations can be unconscious, but such unconscious representations still appear to be consciously accessible, in the sense that they can be brought to consciousness at will.

Finally, in chapter four, I provide a critique of Peter Carruthers’ recent sensory-based account of working memory. According to Carruthers, attention only targets “mid-level” sensory areas, and thus the representations held in working memory will necessarily be sensory based in nature. I disagree. I point out that there is some evidence for attentional modulation outside of modality-specific sensory areas. I also highlight several empirical studies which provide preliminary support for the existence of non-sensory (i.e., amodal) working memory representations.

Attentional processes are critical aspects of the neural, cognitive, and computational mechanisms of decision-making. However, the role of such processes is often not given much focus in decision-making research, especially for studies involving economic decision-making. Here, I present three studies that evaluated the role of attention during decision making. Study 1 evaluated the role of attentional control, such as top-down and bottom-up control, in mediating conflict between internal and external demands on attention to promote optimal task performance in a discrimination decision task. Results from Study 1 provided novel neural insights into the role of attentional control in processing and resolving conflict between internal representations and external stimuli during everyday decision-making. Studies 2 and 3 evaluated the role of selective attention, namely online feature-based selective attention, underlying mechanisms of delay and effort discounting in economic decision-making. Results from these two studies demonstrated the importance of measuring (online and parametrically) and utilizing feature-based selective attention during comparative decision-making tasks to better quantify the cognitive and computational mechanisms underlying behavior and preferences. Taken together, results from all three studies provide important quantitative and qualitative implications for understanding mechanisms of decision-making through the lens of attention.