The Emotional Brain- The Mysterious Underpinnings of Emotional Life-Joseph LeDoux---Book Review

The Emotional Brain- The Mysterious Underpinnings of Emotional Life
Joseph LeDoux
Simon & Schuster Paperbacks
New York London Toronto Sydney

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Emotional responses are mostly generated unconsciously.
We have little direct control over our emotional reactions. anyone who has tried to feak an emotion, or who has been the recipient of a faked one, knows all too well the futility of the attempt. While conscious control over emotions is weak, emotions can flood consciousness. This so because the wiring of the brain at this point in out evolutionary history is such that conncetions from the emotional systems to the cognitive systems are stronger than conncetions from the cognitive systems to the emotional systems.
Emotions easily bump mundane ebents out of awareness, but non-emotional events (like thoughts) do not so easily displace emotions from the mental spotlight-wishing that anxiety or depression would go away is usually not enough.
Finally when emotions occur they become powerful motivators of future behaviors.
Although our emotions are at the core of who we are, they also seem to have their own agenda, one often carried out without our willful participation.
Unfortunately, one of the most significant things ever said about emotion maybe that everyone knows what it is until they are asked to define it.
Humans have found it compelling to separate reason from passion, thinking from feeling, cognnition from emotion.
However, in fact, cognitive science is really a science of only a part of the mind, the part having to do with thinking, reasoning, and intellect. It leaves emotions out. and minds without emotions are not really minds at all. They are souls on ice-cold, lifeless creatures devoid of any desires, fears, sorrows, pains, or pleasures.
In order for you to consciously perceive an apple in front of you in space, the apple must be represented in your brain and that representation must be made available to the conscious part of your mind. But the mental representation of the apple that you consciously perceive is created by the unconscious turnings of mental gears.
The brain has mechanisms for computing the shape, color, location, and movement of objects we see, and the loudness, pitch, and location of sound we hear. If we are asked to say which of two objects is closer or which of two sounds is louder, we can do so, but we cannot explain what operations the brain performed to allow us to reach these conclusions. We have conscious access to the outcome of the computation but not to the computation itself. The processing of physical stimulus features makes possible all other aspects of perception, including our conscious awareness of perceiving something. It is just as well that we are unaware of these processes, as we would be so busy doing the computations that we would never get around to actually perceiving anything if we had to do it all with deliberate concentration.
Just because your brain can do something does not mean that you know how it did it.
The inner workings of important aspects of the mind, including our own understanding of why we do, are not necessarily knowable to the conscious self.
Many emotions are products of evolutionary wisdom, which probably has more intelligence than all human minds together.
There is really nothing more or less subjective about the experience of an emotion than about the experience of the redness of an apple or the menory of eating one.
The brain does not usually function independently of the body. Most emotions involve bodily responses. But no such relation exists between cognitions and actions. In the case of cognitively driven responses, the response is arbitrarily linked to cognition. This is partly why cognition is so powerful-cognitions allow us to be flexible, to choose how we will respond in certain situation. Such responses are used by but are not essential to the cognition.
The conversion of emotions into thoughts has allowed emotion to be studied using the tools and conceptual foundations of cognitive science. There are now numerous computer simulations of appraisal and other emotional processes and some proponents of this AI approach to emotion beleive that emotions can be programmed in computers.
Minds feel as well as think, and feelings involve more than thinking.
Emotion is not merely a collection of thoughts about situations. It is not simply reasoning. It cannot be understood by just asking people what went on in their minds when they had an emotion. Emotions are notoriously difficult to verbalize. They operate in some psychic and neural space that is not readily accessed from consciousness.
How does one go about figuring out the selective channels of information flow in the brain? There are billions of neurons and each give rise to one or more axons. The axons themselves branch, so that the number snapses is far greater than the number of neurons. And each neuron has multiple dendrites that receive thousands of synaptic contacts from many others.
Numerous studies of humans have conditioned autonomic nervous system responses, such as changes in heart rate or in sweat gland activity, by pairing tones or other neutral stimuli with mild shocks.
It is now known that there are multiple memory systems in the brain, each devoted to different memory functions. The brain system that allowed me to hit a baseball is different from the one that allows me to remember trying to hit the ball and failing, and this is still different from the system that made me tense and anxious when I stepped up to the plate after having been beaned the last time up. Though these are each forms of long-term memory they are mediated by different neural networks. Different kinds of memory, like different kinds of emotions and different kinds of sensations, come out of different brain systems.
Sensory processing areas of the cortex receive inputs about external events and create perceptual representations of the stimuli. These representations are then shuttled to the surrounding cortical regions, which, in turn, send further processed representations to the hippocampus. The hippocampus then communicates back with the surrounding regions, which communicate with the neocortex. The maintenence of the memory over the short run requires that the temporal lobe memory system be intact, either because components of this system store the memory trace or because the trace is maintained by interactions between the temporal lobe system and the neocortex. Gradually, over years, the hippocampus relinquishes its control over the memory to the neocortex, where the memory appears to remain as long as it is a memory, which maybe a lifetime.
We can get a pretty good idea about what makes the hippocampus so important for its brand of memory by examining the kinds of inputs that the hippocampus receives from the neocortex. As we mentioned above, the major link between the hippocampus and the neocortex is the transition cortex. This region receives inputs from the highest stages of neocortical processing in each of the major sensory modalities. So once a cortical sensory system has done all that it can do with a stimulus say a sight or a sound, it ships the information to the transition region, where the different sensory modalities can be mixed together. This means that in the transition circuits we can begin to form representations of the world that are no longer just visual or auditory or olfactory, but that include all of these at once. We begin to leave the purely perceptual and enter the conceptual domain of the brain. The transition region then sends these conceptual representations to the hippocampus, where even more complex representaions are created.
The sound of the horn having become a conditioned fear stimulus, goes straight from the auditory system to the amygdala and implicitly elicits bodily responses that typically occur in situations of danger; muscle tention, changes in blood pressure and heart rate, increased perspiration, and so on. The sound also travels through the cortex to the temporal lobe memory system, where explicit declarative memories are activated. You are reminded of the accident. You consciously remember where you were going and who you were with. You also remember how awful it was. But in the declarative memory system there is nothing different about the fact that you were with Bob and the fact that the accident was awful. Both are just facts propositons that can be declared about the experience. It is mediated by the temporal lobe memory system and it has no emotional consequences itself. In order to have an aversive emotional memory, complete with the bodily experiences that come with an emotion, you have to activate an emotional memory system, for example the implicit fear memory system involving the amygdala.
Memory is selective: Not all aspects of an experience are remembered equally well, and the memory improvement produced by emotional arousal may effect some aspects more than others.
Memories are imperfect reconstructions of experiences: Even though a memory of an emotional experience is strong and vivid it is not necessarily accurate. Explicit memories regardless of their emotional implications, are not carbon copies of the experiences that created them.
Memory of emotional events may also be poor: It is sometimes said that emotional events, especially traumatic ones, are accompanied by a selective amnesia for the experience, rather than an improved memory of it.
HIppocampal circuits, with their massive neocortical interconnections, are well suited for establishing complex memories in which lots of events are bound together in space and time. The purpose of these circuits to provide representational flexibility. No particular response is associated with these kinds of memories - they can be used in many different ways in many different kinds of situations. In contrast, the amygdala is more suited as a triggering device for the execution of survival reactions. Stimulus situations are rigidly coupled to specific kinds of responses through the learning and memory functions of this brain region. It is wired so as to preempt the need for thinking about what to do.
If looked at microscopically, which is to say molecularly implicit (unconscious) emotional memory and explicit (conscious) memory of emotion may be indistinguishable. But at the level of neural systems and their functions, these are clearly unique operations of the brain. Although we know much more at this point about the separate operation of these two systems, we are beginning to also see how they interact. And these interactions are at the core of what gives emotional qualities to memories of emotions past.
Emotional habits can be very useful. If you find out that going to a certain water hole is likely to put you face to face with a blood-thirsty predator, then the best thing to do is to avoid going there. But if you stop going to water holes because you become anxious whenever you begin to look for water, or you start drinking less water than you need to maintain your health whenever you do get around to drinking, then your avoidance response has become detrimental to routine life. You have an anxiety disorder.
An emotion is an subjective experience, a passioante invasion of consciousness, a feeling.
Thinking occurs in a mental workspace that has a limited capacity. When you started using the workspace to do the substraction problem you bumped hte stored number out. This workspace is called working memory, a temporary storage mechanism that allows several pieces of information to be held in mind at the same time and compared, contrasted, and otherwise interrelated.
Working memory is pretty much what used to just be called short-term memory. However the term working memory implies not just a temporary storage system but an active processing mechanism used in thinking and reasoning.
That short-term memory has a capacity limit of about seven pieces of information. Borrowing a term from computer technology, memory researchers sometimes refer to temporary storage mechanisms as buffers. It is now believed that a number of specialized buffers exist. For example each sensory system has one or more temporary buffers. These aid in perception, allowing the system to compare what it is seeing or hearing now to what it saw or heard a moment ago. The specialized memory buffers work in parallel, independent of one another.
The stuff in working memory is the stuff we are currently thinking about or paying attention to. But working memory is not a pure product of the here and now. It also depends on what we know and what kinds of experiences we have had in the past. In other words, it depends on long-term memory. In order to be aware that you are looking at a basketball, it is not enough for the basketball to be represented as purely visual pattern by your visual system. The pattern also has to grabbed the attention of the working memory executive. This means that the pattern is what is being held in the visual shart term memory buffer and that the visual buffer as opposed to the auditory or other buffers, is the one with which the executive is working. Only when the visual pattern is matched with information in long-term memory does the visual stimulus become recognized as a basketball. But in addition to being important in figuring out the meaning of information being picked up by lower level speciallized systems, stored knowledge also influences the workings of the lower level systems.
The conscious and unconscious aspects of thought are sometimes described in terms of serial and parallel functions. Consciousness seems to things serially, more or less one at a time, whereas the unconscious mind being composed of many different systems seems to work more or less in parallel. Some cognitive scientists have suggested that consciousness involves a limited capacity serial processor that sits at the top of the cognitive hierarchy above a variety of special purpose processors that are organized in parallel. serial processors create representations by manipulating symbols and we are only conscious of information that is represented symbolically. Information processing by the lower level parallel processors occurs subsymbolically in codes that are not decipherable consciously.
Working memory is the limited capacity serial processor that creates and manipulates symbolic representations.
How something as intangible as feeling could be part of something so tangible as a brain.
--What I am doing is using working memory as an "in principle" way of explaining feelings. I am saying that feelings come about when the activity of specialized emotion systems gets represented in the system that gives rise to conciousness, and I'm using working memory as a fairly widely accepted version of how the latter might come about.
The activation of amygdala outputs that converts an experience into an emotional experience. Amygdala outputs provide basic ingredients that when mixed together in working memory with short-term sensory representations and the long-term memories activated by these sensory representations, create an emotionalexperience.

Direct Amygdala Influences on the Cortex: The amygdala has projections to many cortical areas. In fact as we have already seen the projections of the amygdala to the cortex are considerably greater than the projections from the cortex to the amygdala. In addition to projecting back to cortical sensory areas from which it receives inputs, the amygdala also projects to
some sensory processing areas from which it does not receive inputs.

Amygdala Triggered Arousal: There are a number of indirect channels through which the effects of amygdala activation can impact on cortical processing. An extremely important set of such connections involves the arousal systems of the brain.When you are alert and paying attention to something important, yur cortex is aroused. When you are drowsy and not focusing on anything, the cortex is in the unaroused state. During sleep the cortex is in the unaroused state, except during dream sleep when it is highly aroused. In dream sleep, in fact, the cortex is in a state of arousal that is very similar to the alert waking state, except that it has no access to external stimuli and only processes internal events.
Arousal is important in all mental functions. It contributes significantly to attention, perception, memory, emotion, and problem solving. Without arousal we fail to notice what is going on we don;t attend to the details.But too much arousal is not good either. If you are overaroused you become tense and anxious and unproductive.
Emotional reactions are typically accompanied by intense cortical arousal. Certain emotion theories around mid-century proposed that emotions represent one end of an arousal continuum that spans from being completely unconscious to asleep to awake but drowsy to alert to emotionally aroused. This high level of arousal is in part the explanation why it is hard to concentrate on other things and work efficiently when you are in an emotional state. Arousal helps lock you into the emotional state you are in. This can be very useful but can also be an annoyance.

Bodily Feedback: Activation of amygdala results in the automatic activation of networks that control the expression of a variety of responses: species-specific behaviors (freezing, fleeing, fighting, facila expressions), autonomic nervous system (ANS) responses (changes in blood pressure and heart rate, piloerection, sweating) and hormonal responses (release of stress hormones, like adrenaline and adrenal steroids, peptides into the bloodstream) (GSR)

When cortical sensory buffers that hold the informaton about the currently present sitimuli, working memory executive that keeps track of the short-term buffers, retrieves information from long-term memory, and interprets the contents of the short-term buffers in terms of activated long-term memories, cortical arousal, bodily feedback-somantic and visceral information that returns to the brain during an act of emotional responding - when all of these systems function together a conscious emotional experience is inevitable.
When some components are present and others lacking emotional experiences may still occur depending on what's there and what's not.
Conscious emotional feelings and conscious thoughts are in some sense very similar. They both involve the symbolic representation in working memory of subsymbolic processes carried out by systems that work unconsciously. The difference them is not due to the system that does the consciousness part but instead is due to two other factors. One is that emotional feelings and mere thoughts are generated by different subsymbolic systems. The other is that emotional feelings involve many more brain systems than thoughts.