Thinking begins when information enters the mind. Such information may enter through our eyes or ears; it may enter in the form of a scent or a touch; it may even present itself as an idea or a memory. Yet for thinking to ensue, the brain must detect “data”; it must take hold of the data and center it in conscious awareness. Cognitive scientists describe the detection of information as sensation, and they refer to the centering of that information as attention. Together, these processes initiate the act of thinking.
Cognitive scientists pose several key questions in studying sensation and attention. They ask: What are the sensory mechanics behind information detection—that is, how are the eyes, ears, and so on structured? Once detected by sensory organs, why do some objects or events take precedence over others in conscious awareness? And why does the brain seemingly ignore certain environmental stimuli? For cognitive scientists, answering these questions requires, in part, a detailed picture of brain activity. They believe that a true understanding of sensation and attention demands that one “take the brain apart,” so to speak, and learn how it works. The neurocognitive branch of the discipline leads the way in this regard. Via technologies such as the CAT scan, 1 the PET scan, 2 and the MRI, 3 neurocognitionists actually observe the brain as it encounters and processes new stimuli or previously stored material. Such observations form the basis of several fascinating theories on sensation and attention.
Francis Crick (1994), for example, explains sensation and attention as a function of neuron activity. Neurons are specialized cells that transmit information through the nervous system. 4 Crick argues that each object or event we encounter, whether in the environment or in memory, activates a specific network of neurons. As the neurons of a network fire, information is carried throughout the nervous system. When a neural network’s activity is especially concentrated, the network can direct or focus the brain on the specific stimulus that triggered the activity. According to Crick, every human being possesses thousands of neural networks. Further, he