[MUSIC] So, today I will give you the second introductory lecture that will explain to you some basic facts about the brain anatomy and also cognitive neuro-imaging methods that will be used in our course. So, this lecture will help you to understand the results of the neuroeconomic studies. So during the whole course, we will focus on the neurobiological mechanism of decision making. And to be honest this is a very complex task, and first of all because the brain is a very complex device. The brain consists of billions of neurons, and each neuron has thousands of connections, so all together it makes the most complex device in the universe. Some neuroscientists are really skeptical whether we can really fully understand the system, but other neuroscientists are more optimistic. So brain consist of various cells and first of all consist of neurons. The neuron is our basic unit of the brain. As you remember, neuron consists of their cell body, of dendrites, and of the axon. So dendrites accumulate in formation from other neurons, from sensory organs. Soma or the cell body Integrate this information and produces an action potential. An action potential propagates an axon and induces some neuro mediators to the synaptic cleft, and activate the next neuron or, for example, a muscle. So, if we will simply slice the brain, we will see immediately a large difference between gray and white matter. So, gray matter consists of cell bodies, and most of the neuroeconomic studies focus on the gray matter; on the human cortex. White matter consists of axons. So, basically white matter consists of connections between different brain regions. Anyway, if we will make a closer look inside those white matter, we will find some small clusters of neurons, so called nuclei. So, for example, the nucleus accumbens is a very important area for decision-making. The nucleus accumbens or sometimes we call this region" ventral striatum," the lower portion of striatum is critical for the evaluation of the expected values for the option during decision making. So sometimes we'll also focus on some brain regions inside of the brain. How to navigate within this very complex system, so if you'd really like to know more about the neuroanatomy, about the masses used in neuroecnomics, I strongly recommend you to read more specialized books. So some maze books are available, for example is this book on Cognitive Neuroscience is a nice review of basic facts of human neuro-anatomy and also common neuroscience matters. Today, I will only give you some very basic facts that you need for this course. So we can divide the brain in four major regions. For example into the frontal lobe, parietal lobe, occipital lobe and temporal lobe. During this course we will focus on the frontal lobe. So a lot of really important brain areas are localized in the frontal lobe, and these brain areas are involved in the decision making. So you have to remember that each region in the brain has own label. For example, each sulcus, each gyrus has its own name. For example, central sulcus, pre-central gyrus, postcentral gyrus. But we will not use this labels during this course. So, instead we will use a more abstract way to label different brain regions. For example, we will use dorsal ventral name mention to localize brain region. This dimension refers, this axes refers to animals anatomy. So, dorsal means closer to the back. Ventral, closer to the belly. Since our anatomy is slightly different from the standard animal anatomy, in our brain, dorsal means the upper portion of the brain and ventral means the lower portion of the brain. So when I will talk to you about the ventral striatum, it means this is a lower part of the structure called strait. So, I will use this labels quite a lot during the course. Another important axis is medial, lateral axis. Medial means closer to the central plane of the brain. And lateral means closer to the outer surface of the hemispheres. So, for example, the medial cortex represents the inner surface of the hemispheres. Another important label that will be often used in this course is orbital cortex. Orbital cortex means the cortex localized above our eyes. So when I'm talking to you about the orbital cortex it means I refer to the cortex localized just above our eyes. So when you will make a look to some regions in the prefrontal cortex, you can notice dorsolateral prefrontal cortex. We will discuss this region quite a lot. This region is involved into the self control, into the rational decision making. So, dorsolateral means the specific location in the brain. We will also discuss orbitofrontal cortex. And orbitofrontal cortex is a cortex above our eyes. So, this scheme summarizes a key areas in our frontal cortex that are involved into the decision making: orbitofrontal cortex is the cortex above our eyes. Dorsolateral prefrontal cortex, cortex on the outer surface of the hemispheres that is ligated in the upper portion of the brain and, ventromedial prefrontal cortex. This is a major portion of the prefrontal cortex, localized in the inner surface of the hemispheres. So, let's quickly discuss how the brain processes sensory information. So, different brain areas are specialized in different sensory information. For example, the occipital cortex is involved into the process in causing visual information. This is so called visual cortex. So in the temporal cortex we can find the auditory cortex. So if you would stimulate this brain region you can evoke illusions of different sounds. So some brain areas are really specialized. Some brain areas are involved in different functions. So, if you would be interested in the details of the sensory information processing by our brain, please read more specialized handbooks. So, now I will give you the major metaphor of Cognitive Neuroscience that explains how our brain processes sensory information. So, visual, for example, information first comes to our visual cortex. So, first our primary visual cortex, sometimes labeled as the area V1, processes very basic aspects of the visual information. So, for example, if these neurons, they react to their local contrast, so this neurons are kind of spatial temporal filters that are sensitive to the very basic aspects of the visual information. The next information is transferred to the higher visual cortex, for example the area V4, and neurons in this area are sensitive to more complex patterns to more complex features of the visual information. And next, more higher order visual cortex is involved and neurons in this area are sensitive to very complex patterns, for example two faces. So, visual information is processed step by step from very simple features to very complex features. So, at the end, brain creates a image, a kind of internal model of the visual object. And, Neuroeconomics assumes that, after this stage, the decision making process takes place. So, first, sensory evidences for different options are accumulated by the brain and next our brain makes decisions. It compares options and select certain behavioral patterns. So overall, according to Neuroeconomics theory, when we make a decision, when we make a selection between two options, first our brain processes objects and next we make a decision. So, at the next stage, decision making neurons are processing the information and create and produce a decision. So, let's now discuss the major methods used in neuroeconomics methods that help us to understand neuro biological mechanisms of decision making. [SOUND]
