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I find the topic(s) of 'thought and physiology' fascinating. Since Thursday's class, I did some searching around on the internet, and found an interesting article published in 'Nature Neuroscience' by a group at the University of Texas at Austin. Their study, published in 2005, suggests that neurons experience changes across their dendrites during the processes of learning and memory recall. The research shows that ion channels distributed in the dendritic membrane change during a simulated learning task and that this requires the rapid production of new proteins- "Our new work strongly supports the idea that learning involves changes in dendrites,"                                                                                                                                                                                            To record the changes during learning, cells from the rat hippocampus (an important area of the brain for short-term memory) were electrically stimulated to mimic the electrical stimulus that shoots through neurons when animals perform a learning task. The researchers found that when stimulated with electrical bursts, hippocampus neurons showed h-channel plasticity and a rapid increase in the synthesis of h-channel proteins.  Thought and Memory researchers know that protein synthesis in neurons is related to long-term memory, because protein synthesis inhibitors block long-term memory in animals.                                                       Researchers have traditionally focused on the role that changes at synapses play in learning (Dendrites--the thin branch-like extensions of a neuron cell--receive many inputs from other neurons that transmit information through contact points called synapses) , with the outcome being that they change in ways that make it easier for connected neurons to pass information. This study is unusual in the sense that it show that learning and memory are likely to not only involve changes at synapses, but also in dendrites. They found that h-channels, which are distributed throughout the dendrite membrane and allow the passage of potassium and sodium ions into and out of the neuron, are altered during learning."The h-channels undergo plasticity, not near the synapse but probably throughout the dendritic tree," says one of the authors.   Based on this article I would say that "thought" can affect matter directly although it would be more accurate to say that "thought" is a physiological process involving physiological (read: material) changes and mechanisms.