Accounting and Economics
Broadly viewed, economics is concerned with the production and allocation of resources, and accounting is concerned with measuring and reporting on the production and allocation of resources. Corporate financial reporting, income tax reporting, and produc
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each particular time over a set of experimental trials; here there is much activation immediately after the experimental event when looking across trials.
neuroeconomics
Imaging
The fundamental unit of activity of the brain is the neuron. It ingests nutrients, receives chemical signals from other neurons, and fires (produces electro-chemical action potentials), which results in sending chemical signals (that is, neurotransmitters) to other neurons. Human brains are estimated to have as many as 100 billion neurons. A first task of neuroeconomics is to accumulate information about the behaviour of collections of neurons and how they interact to produce economic choices.
Research methods
Research methods employed include single neuron recordings of non-human primates, often macaque monkeys, brain scans (such as functional magnetic resonance imaging, fMRI) of humans and comparative studies of lesioned and normal patients.
Single cell recording
Only in rare instances is it possible to target specific neurons of living human beings (for example, when someone is having open brain surgery). Because many brain structures of non-humans correspond to human brain structures, it is possible to use results from nonhuman studies to postulate neuronal structures that function in human brains making economic choices. The method for making observations of a neuron's behaviour using monkeys is single cell recording. In this approach specific groups of neurons are targeted. Electrodes are implanted in individual neurons in the group. When a neuron fires, an electrical impulse is sent to a recording device. Figure 1 shows a typical result for a specific neuron in a targeted group of neurons. The distance along the horizontal axis represents the number of seconds into the experimental trial. In this picture an experimental event such as the receipt of reward occurred roughly one fifth of the way through the experimental trial. The vertical axis represents the sum of activations for this neuron at
In studying the human brain researchers employ scanning, for example, functional magnetic resonance imaging (fMRI). fMRI surrounds the economic agent with a strong magnetic field. When specific neurons are engaged in a task, capillaries near those neurons carry more oxygenated blood than capillaries surrounding neurons not engaged in the task. fMRI assesses where such oxygenated blood is. These assessments can be represented in an image indicating areas of the brain that activate differentially. A typical scan produces an image like that in Figure 2. The image shows the implicit activation in the superior parietal lobe (upper-left darkened spot of image) when a subject performs certain numerical operations. The whitened area surrounding the darkened spot suggests the increasing activation around the location. An fMRI captures brain activity at a much coarser level than single unit recording; it cannot isolate some brain structures in humans to the same degree as single unit recording can isolate neuronal activation in mo
