5Motivation and Emotion

Introduction

Happiness, anger, love, sorrow, confusion and excitement. All these words describe some kind of abstract inner states in us, humans, many of them difficult for us to control. We usually call them feelings or emotions. But what is the reason that we are able to "feel"? Where do emotions come from and how are they caused? And are emotions and feelings the same thing? Or are we supposed to differenciate?

Several human face expressions connected to emotions (GFDL - Ddeunert)

These are all questions that Cognitve Psychology deals with in Emotion Research. According to a scientific definition feelings are subjective experienced emotions, which are connected with motivation in what we want, need, and desire. It took quite long to get to such a brief definition, which is right now just a definition that separates these two terms. The roots of studying emotions go back until the very beginning of the history of Philosophy over 2000 years ago, where Philosophers like Plato already thought about the nature of emotions. Throughout the time it became more and more important in other scientific disciplines. Especially in psychology, where the term "feelings" got separated from the term "emotions".The psychologists tried to provide a definition and build theories to desribe it.

Among those, the most important ones are the "James-Lange theory", the "Canon-Bard theory" as well as the "Two factor theory" (see following chapter). The last theory will lead us to a further extend of disciplines involved in this research process. The increase of Neuroscience and especially its powerful tools, that were developed in the recent past, allow today's scientists to get a good picture of the brain, understand its complex processes better and try to discover the origin of emotions. But there is still a lot which we do not know or cannot explain in respect of emotions, even today. Nevertheless, research of emotions has made a big step towards understanding its essence, since the birth of Cognitive Science and especially Cognitive Psychology.

The following chapter gives an overview for a better understandíng of emotions. It provides information about theories and its functions, the causation of emotions in the human brain, its processes and their role in the human body in connection with motivation. We will try to show different points of view in the issue of emotions, the actual state of research, and some examples of psychologist experiments. In the end we will outline some application areas of scientific emotion research, especially concerning brain deseases.

Motivation - about drives and motives

Motivation is an extended notion, which refers to the starting, controlling and upholding of corporal and psychic activities. It is declared by inner processes and variables which are used to explain behavioural changes. Motivations are commonly separated into two types. Drives describe acts of motivation like thirst or hunger that have primarily biological purposes. The acts of motives, on the other hand, are driven by primarily social and psychological mechanisms. Motivation is an interceding variable, which means that it is a variable that is not directly observable. Therfore, in order to study motivation, one must approach it through variables which are measurable and observable:

1. Observable terms of variation (independent variables)

2. Indicators of behaviour (dependent variables), e.g.: rate of learning, level of activity, ...

There are two major methodologies used to manipulate drives and motives in experiments:

One method is stimulation. Aversive attractions could initiate motives such like shocks, heat, cold or loud noise. Sexual drives were also activivated by attractions which lead positive affective states.

Deprivation means that you prohibit the access of nutrition or water to an animal. As a result it leads it to motives or drives which are not common for this special situation. It is known that human for example try to avoid social deprivation. So everyone has the inherent motive to maintain the contact with other humans and be a part of a social structure. Nevertheless, a reader might imagine some people who desire to be alone and seek a life of isolation and reduced social contact. These people may be the exceptions to this hypothesis, but they may also have some other, more pressing, motives or drives which induce them to behave in this way. Think of the Russian mathematician Grigori Perelman(40) who seems to have recently proved the mathematical proof of Poincaré: “Everything without a hole is a sphere.”. He prefers to stay alone and lessened his social contacts because of his belief (motive) that modern society is not ruled by ethical norms.

So, one may generalize that individuals are able to resist certain motives via personal cognitive states. The ablity of cognitive reasoning and willing is human like and the reason for much psychological deseases which indicates that the human is not able to handle all rising mental states. Humans are able to manipulate their motives which make sure that they have the motive to do so but the real emotional and psychlogical causales are unclear. This introduces the problem that the entity of consciousness, unconsciouness and what ever else could be take into account is pretty unknown. However it is not able to handle the discussion in this chapter so far. Motivation is the link from internal events to external one and could maybe bring light into it. A theory of motivations was conceived by Abraham Maslow in 1970 (Maslow's hierarchy of needs). He considered two kinds of motivation:

1. The defected motivation (Mangelmotivation) brings humans to reconsider their psychical and physical balance.

2. The other one is the adolescence motivation (Wachstumsmotivation) which get people to pass old events and states of their personal development.

Maslow argues that everyone has a hierarchy of needs.

Regarding to this, our innate needs could be ordered in a hierarchy, starting at the “basic” ones towards the most human one. The idea is, that the human is ruled by lower needs as long as they are not satisfied. If they are satisfied in a adequate manner he dealed with higher needs. Compare to Chapter Attention.

Hierachy of needs, Maslow (1970) (GFDL - Ddeunert)

In the following it is not intended to explain all facettes of motivation and behaviour and drives and motives. The framework of this part is going to state the relation between motivation, emotion and cognitve psychology.

What is an emotion?

Emotion is not something shameful,subordinate, second-rate; it is a supremely valid phase of humanity at its noblest and most mature. -- Joshua Loth Liebman

The very old question "What is an emotion?" can only be answered partially in this chapter,according to the results of current research, because the entire topic as itself is huge enough to write whole books about. First we should distinguish between feelings and emotions. f.e. The feeling of hunger is not an explicit emotion,more a recognition of sensory input. Emotions could be roughly described by the process of evaluation of such an event, namely become aware of that feeling. Awareness is close connected with changes in the environment or in the psychophysiological state. Why recognize changes rather than stable states? An answer could be that changes are an important indicator for our situation. They show that our situation is unstable. Pay attention or focus on that might increase the chance to survive. A change bears more information than repetitive events.This appears
more exciting. Repitition reduces excitement. If we think that we got the most important information from a situation or an event,we become unaware of such an event or certain facts.

Current research in this field suggest that changes are needed to emerge emotions,so we can say that it is strong attention dependent. The event has to draw our attention.No recognition, no emotions. But do we have always an emotional evaluation, when we are aware of certain events? How has the change to be relevant for our recognition? Emotional changes are highly personal significant, saying that it needs a relation to our personal self. Significance presupposes order and relations.Relations are to meaning as colours are to vision: a necessary condition,but not its whal content. One determines the significance and the scope of a change by f.e. event´s impact (event´s strengh),reality,relevance and factors related to the background circumstances of the subject. We feel no emotion in response to change which we perceive as unimportant or unrelated. Roughly one can say that emotions express our attitude toward unstable significant objects which are somehow related to us. This is also always connected with the fact that we have greater response to novel experience. Something that is unexpected or unseen yet. When children get new toys, they are very excited at first, but after a while one can perceive,or simply remember the own childhood, that they show less interest in that toy. That shows, that emotional response declines during time. This aspect is called the process of adaptation. The threshold of awareness keeps rising if stimulus level is constant. Hence, awareness decreases. The organism withdraw its consciousness from more and more events. The person has the pip,it has enough. The opposite effect is also possible. It is known as the process of facilitation. In this case the threshold of awareness deminishes. Consciousness is focusing on increasing number of events. This happens if new stimuli are encountered. The process of adaptation might prevent us from endlessly repetitive actions. A human would not be able to learn something new, if got catched in an infinite loop. The emotional environment contains not only what is, and what will be, experienced but also all that could be, or that one desires to be, experienced ; for the emotional system, all such possibilities are posited as simultaneously there and are compared with each other. Whereas intellectual thinking expresses a detached and objective manner of comparison, the emotional comparison is done from a personal and interested perspective; intellectual thinking may be characterized as an attempt to overcome the personal emotional perspective. It is quite difficult to give an external description of something that is related to an intrinsic, personal perspective. But it is possible. In the following we will see the most popular theories, and an external view with focus on the neuronal networks responsible for emotions.

Functional Theories

James-Lange Theory

The James-lange theory states that a specific stimulus causes a certain emotion. f.e. When a person sees a spider he or she might experience fear. Alternatively, when a person sees a lovely dog, this person might experience happiness. One problem with this theory is that it is based on the experience of different bodily changes. That means that the stimuli causes a change in the bodily state of which the person is aware and hence relates the change experienced to the event and equates it with an emotion. However, people paralyzed from the neck down, who have little awareness of sensory input are still able to experience emotions. Also, research has shown, that the same physiological states occur across many different emotions. So, an extension of this theory was necessary. This leads us to the Cannon-Bard Theory

Cannon-Bard Theory

This theory states that emotions emerge when the thalamus percieves an event or an object. According to this theory, physiological changes in the body and the processing of information in the brain influence the experience of emotions, because the thalamus conveys information to the skeletal muscles and autonomic nervous system.Hence on the way from stimulus to an experienced emotion the thalamus is responsible for a physiological response and a cognitive evaluation. Furthermore this theory states, that the experience of emotions could be different in the same physiological state what fills the lack of the James-Lange Theory. The cerebral cortex plays an important role in evaluating the emotional significance of the stimulus.

Two Factor Theory

In this theory it is assumed that emotional experience is the outcome of physiological arousal in correlation to a cause for that arousal. Schachter and Singer (1962) did well known studies in this field of research. They induced a physiological arousal in their subjects by injection of a chemical substance. Given a situation, they changed the action of the experimenters in order to switch the emotional tone of the subject. According to their results, they claimed that one can manipulate a subject into different emotional states from a given state of physiological activation. The interpretation of a certain emotion depends on the physiological state in correlation

to the subjects circumstances. It is very context dependent.

More recent research has shown, that different emotions have certain physiological signatures. Patterns of heart rate, electrodermal response, and physiological changes in the brain have been associated with specific emotions.

The Neural Correlate of Emotion

Emotions are processed through several brain regions as you can see on the picture (Papez.jpg). This Network is called "Circuit of Papez", after James W. Papez. The contemporary interpretation of the roles of the different parts have changed, but the parts have remained the same.

There are 2 important pathways in the processing of emotions: the subcortical pathway, or "low road" and the cortical way, the "high road". The "low road" processes the sensory input "quick and dirty", that means it responds very fast but does not analyze the stimulus very well. It is responsible for quick reactions, like ducking if a you ride your bike and there is suddenly a tree limb in front of your head. The "high road" is responsible for the conscious, aware processing of the emotion. It is slower because there are a lot more neurons involved.(LeDoux)

Let's take a closer look at some important parts of Papez circuit:

Circuit of Papez

Circuit of Papez (GFDL - Ddeunert)

The Hippocampus

Once seen as the Hub of Information processing, contemporary research has shown that the hippocampus plays a bigger role in memory, than in emotion processing. Nevertheless it is still important but instead of generating emotion it plays a modulatory role in the affective response to a stimulus. The hippocampus "puts thing in perspective" exerting a modulating effect on output from the amygdala, the real hub of emotion processing.

The Thalamus

The Cerebral Cortex

The cerebral cortex plays an important role in analyzing and understanding emotional behavior and expression. In contrast to the limbic system the cortex is responsible for cognitive emotional processing. Researchers use brain scanning or observe patients with known X cortical damage to elucidate the function of the cerebral cortex in emotional processes. Link: chapter 4.

The prefrontal cortex (PF Connectivity between the PFC and the brain. (GFDL - Ddeunert)
is well known for rational and analytical cognitive functions and can be seen as the analytical part of rational-emotional decision making.

The role the cortex plays in aspects of emotional functions can be summarized as follows:

1. the cognitive ability to interpret emotional information (perceiving, comprehending and recalling emotionally meaningful content)

2. the ability to express emotions (e.g. facial expression, gesture and tone of voice)

3. and the experience of emotions or emotional state

Today there are known many syndromes and deseases which describe lesions of the cerebral cortex. Anosognosia is attributed to lesions in the right hemiphere.

This syndrome is well described in detail by A. Damasio in his book called “Descartes` Error”. People suffering from anosognosia are not aware of their inabilities. The inabilties could for example occur from strokes.

In further researches and experiments it was shown that lateral hemispherical damages causes different emotional impairments. As a result of it you can ascribe the left and the right hemisphere dedicated functions in emotional processing:

The right hemisphere is responsible for nonverbal skills and understanding of emotions. So patients with damages in their right hemisphere are according to the circumstances unable of Discriminate between emotional faces, neither there are able to name emotional scenes, nor matching emotional expressions or grouping both pictorially presented and written emotional scences and faces. Therefore those people suffer addional social interferences. To describe one situation you allowed to imagine a communication with such a person. Within the talk you might recognize queerly responses of your opponent. So it is possible that he or she make inappropriate turn within the your conversation, or gives inconsequential reasons for something. Futhermore it is typical for them to laugh at inproperly points of the talk.

The left hemisphere contains the main regions of language processing ( Broca's , Wernicke`s area). So it is not surprising that damages to this area and the lobes in general results in impairments of language processing. Researchers have discovered that the left hemisphere processes ideas about emotions and verbal emotional content.

The Amygdala

Anatomy

The amygdala is the most important part in the processing of emotion. It is a bilateral organized nuclei complex, located in the anterior, medial temporal lobe (Adolphs & Damasio, 2000; Nieuwenhuys, Voogd & Huijzen, 1991).

It can be subdivided into several nuclei with distinct functional traits: the centromedial nucleus, the cortical nucleus and the basolateral complex, which can be subdivided further into the lateral, the basal and the accessory basal nuclei.

The amygdalae send impulses to the hypothalamus for activation of the sympathetic nervous system, to the reticular nucleus for increased reflexes, to the nuclei of the trigeminal nerve and facial nerve for facial expressions of fear, and to the ventral tegmental area, locus ceruleus, and laterodorsal tegmental nucleus for activation of dopamine, norepinephrine and epinephrine.

The cortical nucleus is involved in the sense of smell and pheromone-processing. It receives input from the olfactory bulb and olfactory cortex. The lateral amygdalae, which send impulses to the rest of the basolateral complexes and to the centromedial nuclei, receive input from the sensory systems. The centromedial nuclei are the main outputs for the basolateral complexes, and are involved in emotional arousal in rats and cats.

Functions

In 1937 Heinrich Klüver and Paul Bucy described the behavoir of monkeys with large temporal lobe lesions. The affected monkeys showed extremely abnormal reactions to their environment. Namely a loss of fear of things they where afraid before the brain damage, attempts to engage in sexual behaviors with other species and to ingest things indiscriminately. They seemed to suffer a kind of "psychic blindness" which kept them from understanding the affective properties of the things they perceived. This put the amygdala in the center of emotion research. Today we know that the Amygdala is one of the most important brain regions for emotional processing. It plays a key role in the interpretation of social signals of emotion, emotional conditioning (especially fear) and the consolidation of emotional memories. We will discuss this now more in detail:

Processing social signals of emotion

Very famous experiments measure responses to emotional facial expressions. They give evidence that the amygdala is responsible for the recognition of facial expressed emotions. There are different methods to measure these responses. For example, single unit recording, which allows to measure the activity of only a few neurons. Single unit recording experiments on animals, showed that the amygdala neurons responded differently to different faces. Also, they responded selectively to dynamic social stimuli (like for example approach behavior) (1). There are also studies on people with amygdala lesions who suffered from difficulties in the processing of emotional facial expressions(2,3,4).

Neuroimaging studies also support these results (PET: Morris et al., fMRi: Breiter et al.) In addition, there are studies on responses to emotional vocal expressions, especially the vocal expression of fear, which give evidence that the amygdala is selective for certain emotions(5). Recapitulating we can say, that the amygdala is extremely important for the processing/understanding of emotional expressions and therefore for social life.

Emotional conditioning

We will explain using the example fear-conditioning. That means that a meaningless stimuli is combined with a naturally threatening event (e.g. a shock). If the stimulus appears alone after the conditioning it causes the same reaction. For example, a higher pulse. A big role in this phenomenon play the two different routes of emotion we discussed before:

• The direct thalamo-amygdala-route is responsible for the fast reaction to a stimulus. For 54 | Cognitive Psychology and Neuroscience

Motivation and Emotion

being fast it lacks on detailanalysis. • The thalamo-cortico-amygdala pathway handles the more complex analysis of the situation.

The role of the amygdala in fear-conditioning is confirmed by several experiments with people who suffer from certain brain lesions. Angrilli and colleagues for example report about a man with extensive right amygdala damage showed reduced startle response to a sudden burst of white noise and was also relatively immune to fear conditioning. Bechara and colleagues report about a patient with bilateral amygdala damage. He also failed fear-conditioning to aversive stimuli, but he could report facts about the conditioning experience. Another patient suffered from hippocampal damage. He was successfully fear-conditioned but had no explicit memory of the conditioning procedure.

Emotional memories

There are different studies which indicate, that patients better memorize emotional aspects of stories. This is not the case for people who suffer from certain amygdala damage (6). If you want to learn more about memory please take a look in the memory chapter.

References

Books

• Zimbardo, Philip G. (1995, 12th edition). Psychology and Life. Inc. Scott, Foresman and Company, Glenview, Illinois.

ISBN 020541799X

• Banich,Marie T. (2004). Cognitive Neurosciene and Neuropsychology. Housthon Mifflin Company.

ISBN 0618122109

• Robert A. Wilson and Frank C. Keil. (2001). The MIT Encyclopedia of Cognitive Sciences (MITECS). Bradford Book.

ISBN 0262731444

• Antonio R. Damasio. (1994) reprinted (2005). Descartes' Error: Emotion, Reason and the Human Brain. Penguin Books.

ISBN 014303622X

• Antonio R. Damasio. (1999). The Feeling of what Happens. Body and Emotion in the Making of Consciousness. Harcourt Brace & Company.

ISBN 0099288761

• Aaron Ben-Ze'ev (Oct 2001).The Subtlety of Emotions.(MIT CogNet). ISBN 0262523191

Journals

• The emotional brain. Tim Dalgleish.

• (1) Leonard, C.M., Rolls, E.T., Wilson, F.A.W. & Baylis, C.G. Neurons in the amygdala of the monkey with responses selective for faces.

Behav. Brain Res. 15, 159-176 (1985)

• (2)Adolphs, R., Tranel, D., Damasio, H. & Damasio, A. Impaired recognition of emotion in

facial expressions following bilateral damage of the human amygdala. Nature 372, 669-672 (1994)

• (3)Young, A. W. et al. Face processing impairments after amygdalotomy. Brain 118, 15-24 (1995)

• (4)Calder, A. J. et al. Facial emotion recognition after bilateral amygdala damage: Differentially severe impairment of fear.

Cognit. Neuropsychol. 13, 699-745 (1996)

• (5)Scott, S. K. et al. Impaired auditory recognition of fear and anger following bilateral amygdala lesions.

Nature 385, 254-257 (1997)

• (6)Cahill, L., Babinsky, R., Markowitsch, H. J. & McGaugh, J. L. The amygdala and emotional memory.

Nature 377, 295-296 (1995)

• (7)Wood, Jacqueline N. and Grafman, Jordan (02/2003). Human Prefrontal Cotex. Nature Reviews/ Neuroscience

• (8)Brothers, L. , Ring, B. & Kling, A. Response of neurons in the macaque amygdala to complex social stimuli.

Behav. Brain Res. 41, 199-213 (1990)

Links

• Dana Foundation and the Dana Alliance: The Site for Brain News

• Brain Facts: PDF