Emotion is a mental state variously associated with thoughts, behavioural responses, a degree of pleasure or displeasure. There is no scientific consensus on a definition. Emotion is intertwined with mood, personality and motivation. Research on emotion has increased over the past two decades with many fields contributing including psychology, endocrinology, history, sociology of emotions, computer science; the numerous theories that attempt to explain the origin, neurobiology and function of emotions have only fostered more intense research on this topic. Current areas of research in the concept of emotion include the development of materials that stimulate and elicit emotion. In addition PET scans and fMRI scans help study the affective picture processes in the brain."Emotions can be defined as a positive or negative experience, associated with a particular pattern of physiological activity." Emotions produce different physiological and cognitive changes. The original role of emotions was to motivate adaptive behaviors that in the past would have contributed to the passing on of genes through survival and kin selection.
In some theories, cognition is an important aspect of emotion. Those acting on the emotions they are feeling may seem as if they are not thinking, but mental processes are still essential in the interpretation of events. For example, the realization of our believing that we are in a dangerous situation and the subsequent arousal of our body's nervous system is integral to the experience of our feeling afraid. Other theories, claim that emotion is separate from and can precede cognition. Consciously experiencing an emotion is exhibiting a mental representation of that emotion from a past or hypothetical experience, linked back to a content state of pleasure or displeasure; the content states are established by verbal explanations of experiences, describing an internal state. Emotions are complex. According to some theories, they are states of feeling that result in physical and psychological changes that influence our behavior; the physiology of emotion is linked to arousal of the nervous system with various states and strengths of arousal relating to particular emotions.
Emotion is linked to behavioral tendency. Extroverted people are more to be social and express their emotions, while introverted people are more to be more withdrawn and conceal their emotions. Emotion is the driving force behind motivation, positive or negative. According to other theories, emotions are not causal forces but syndromes of components, which might include motivation, feeling and physiological changes, but no one of these components is the emotion. Nor is the emotion an entity that causes these components. Emotions involve different components, such as subjective experience, cognitive processes, expressive behavior, psychophysiological changes, instrumental behavior. At one time, academics attempted to identify the emotion with one of the components: William James with a subjective experience, behaviorists with instrumental behavior, psychophysiologists with physiological changes, so on. More emotion is said to consist of all the components; the different components of emotion are categorized somewhat differently depending on the academic discipline.
In psychology and philosophy, emotion includes a subjective, conscious experience characterized by psychophysiological expressions, biological reactions, mental states. A similar multicomponential description of emotion is found in sociology. For example, Peggy Thoits described emotions as involving physiological components, cultural or emotional labels, expressive body actions, the appraisal of situations and contexts; the word "emotion" dates back to 1579, when it was adapted from the French word émouvoir, which means "to stir up". The term emotion was introduced into academic discussion as a catch-all term to passions and affections; the word emotion was coined in the early 1800s by Thomas Brown and it is around the 1830s that the modern concept of emotion first emerged for English Language. "No one felt emotions before about 1830. Instead they felt other things - "passions", "accidents of the soul", "moral sentiments" - and explained them differently from how we understand emotions today."Some cross cultural studies indicate that the categorization of "emotion" and classification of basic emotions such as "anger" and "sadness" are not universal and that the boundaries and domains of these concepts are categorized differently by all cultures.
However, others argue that there are some basic universal but spurious bases of emotions in some cultures. In anthropology, an inability to express or perceive emotion is sometimes referred to as alexithymia; the Oxford Dictionary definition of emotion is "A strong feeling deriving from one's circumstances, mood, or relationships with others." Emotions are responses to significant external events. Emotions can be occurrences or dispositions, short-lived or long-lived. Psychotherapist Michael C. Graham describes all emotions as existing on a continuum of intensity, thus fear might range from mild concern to terror or shame might range from simple embarrassment to toxic shame. Emotions have been described as consisting of a coordinated set of responses, which may include verbal, physiological and neural mechanisms. Emotions have been categorized, with some relationships existing between emotions and some direct oppos
Anterograde amnesia is a loss of the ability to create new memories after the event that caused amnesia, leading to a partial or complete inability to recall the recent past, while long-term memories from before the event remain intact. This is in contrast to retrograde amnesia, where memories created prior to the event are lost while new memories can still be created. Both can occur together in the same patient. To a large degree, anterograde amnesia remains a mysterious ailment because the precise mechanism of storing memories is not yet well understood, although it is known that the regions involved are certain sites in the temporal cortex in the hippocampus and nearby subcortical regions. People with anterograde amnesic syndromes may present with varying degrees of forgetfulness; some with severe cases have a combined form of anterograde and retrograde amnesia, sometimes called global amnesia. In the case of drug-induced amnesia, it may be short-lived and patients can recover from it. In the other case, studied extensively since the early 1970s, patients have permanent damage, although some recovery is possible, depending on the nature of the pathophysiology.
Some capacity for learning remains, although it may be elementary. In cases of pure anterograde amnesia, patients have recollections of events prior to the injury, but cannot recall day-to-day information or new facts presented to them after the injury occurred. In most cases of anterograde amnesia, patients lose declarative memory, or the recollection of facts, but they retain nondeclarative memory called procedural memory. For instance, they are able to remember and in some cases learn how to do things such as talking on the phone or riding a bicycle, but they may not remember what they had eaten earlier that day for lunch. One extensively studied anterograde amnesiac patient, codenamed H. M. demonstrated that despite his amnesia preventing him from learning new declarative information, procedural memory consolidation was still possible, albeit reduced in power. He, along with other patients with anterograde amnesia, were given the same maze to complete day after day. Despite having no memory of having completed the maze the day before, unconscious practice of completing the same maze over and over reduced the amount of time needed to complete it in subsequent trials.
From these results, Corkin et al. concluded despite having no declarative memory, the patients still had a working procedural memory. This supports the notion that declarative and procedural memory are consolidated in different areas of the brain. In addition, patients have a diminished ability to remember the temporal context in which objects were presented. Certain authors claim the deficit in temporal context memory is more significant than the deficit in semantic learning ability; this disorder is acquired in one of four ways: One cause is benzodiazepine drugs such as. This has been recorded in non-benzodiazapine sedatives or "z-drugs" which act on the same set of receptors. A second cause is a traumatic brain injury in which damage is done to the hippocampus or surrounding cortices, it may be caused by a shocking event or an emotional disorder. Illness, though much rarer, can cause anterograde amnesia if it causes encephalitis, the inflammation of brain tissue. There are several types of encephalitis: one such is herpes simplex encephalitis, which, if left untreated, can lead to neurological deterioration.
How HSV gains access to the brain is unknown. It is present in the limbic cortices. Damage to specific areas can result in reduced or eliminated ability to encode new explicit memories, giving rise to anterograde amnesia. Patients suffering from anterograde amnesia may have episodic, semantic, or both types of explicit memory impaired for events after the trauma that caused the amnesia; this suggests that memory consolidation for different types of memory takes place in different regions of the brain. Despite this, current knowledge on human memory is still insufficient to "map out" the wiring of a human brain to discover which parts of which lobe are responsible for the various episodic and semantic knowledge within a person's memory. Amnesia is seen in patients who, for the reason of preventing another more serious disorder, have parts of their brains known to be involved in memory circuits removed, the most notable of, known as the medial temporal lobe memory system, described below. Patients with seizures originating in the MTL may have both structures removed.
In addition, patients with tumors who undergo surgery will sustain damage to these structures, as is described in a case below. Damage to any part of this system, including the hippocampus and surrounding cortices, results in amnesic syndromes; this is why people who suffer from strokes have a chance of developing cognitive deficits that result in anterograde amnesia, since strokes can involve the temporal lobe in the temporal cortex, the temporal cortex houses the hippocampus. Anterograde amnesia can be caused by alcohol intoxication, a phenomenon known as a blackout. Studies show rapid rises in blood alcohol
The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. The brain is located in the head close to the sensory organs for senses such as vision; the brain is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains 14–16 billion neurons, the estimated number of neurons in the cerebellum is 55–70 billion; each neuron is connected by synapses to several thousand other neurons. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. Physiologically, the function of the brain is to exert centralized control over the other organs of the body; the brain acts on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. This centralized control allows coordinated responses to changes in the environment.
Some basic types of responsiveness such as reflexes can be mediated by the spinal cord or peripheral ganglia, but sophisticated purposeful control of behavior based on complex sensory input requires the information integrating capabilities of a centralized brain. The operations of individual brain cells are now understood in considerable detail but the way they cooperate in ensembles of millions is yet to be solved. Recent models in modern neuroscience treat the brain as a biological computer different in mechanism from an electronic computer, but similar in the sense that it acquires information from the surrounding world, stores it, processes it in a variety of ways; this article compares the properties of brains across the entire range of animal species, with the greatest attention to vertebrates. It deals with the human brain insofar; the ways in which the human brain differs from other brains are covered in the human brain article. Several topics that might be covered here are instead covered there because much more can be said about them in a human context.
The most important is brain disease and the effects of brain damage, that are covered in the human brain article. The shape and size of the brain varies between species, identifying common features is difficult. There are a number of principles of brain architecture that apply across a wide range of species; some aspects of brain structure are common to the entire range of animal species. The simplest way to gain information about brain anatomy is by visual inspection, but many more sophisticated techniques have been developed. Brain tissue in its natural state is too soft to work with, but it can be hardened by immersion in alcohol or other fixatives, sliced apart for examination of the interior. Visually, the interior of the brain consists of areas of so-called grey matter, with a dark color, separated by areas of white matter, with a lighter color. Further information can be gained by staining slices of brain tissue with a variety of chemicals that bring out areas where specific types of molecules are present in high concentrations.
It is possible to examine the microstructure of brain tissue using a microscope, to trace the pattern of connections from one brain area to another. The brains of all species are composed of two broad classes of cells: neurons and glial cells. Glial cells come in several types, perform a number of critical functions, including structural support, metabolic support and guidance of development. Neurons, are considered the most important cells in the brain; the property that makes neurons unique is their ability to send signals to specific target cells over long distances. They send these signals by means of an axon, a thin protoplasmic fiber that extends from the cell body and projects with numerous branches, to other areas, sometimes nearby, sometimes in distant parts of the brain or body; the length of an axon can be extraordinary: for example, if a pyramidal cell of the cerebral cortex were magnified so that its cell body became the size of a human body, its axon magnified, would become a cable a few centimeters in diameter, extending more than a kilometer.
These axons transmit signals in the form of electrochemical pulses called action potentials, which last less than a thousandth of a second and travel along the axon at speeds of 1–100 meters per second. Some neurons emit action potentials at rates of 10–100 per second in irregular patterns. Axons transmit signals to other neurons by means of specialized junctions called synapses. A single axon may make as many as several thousand synaptic connections with other cells; when an action potential, traveling along an axon, arrives at a synapse, it causes a chemical called a neurotransmitter to be released. The neurotransmitter binds to receptor molecules in the membrane of the target cell. Synapses are the key functional elements of the brain; the essential function of the brain is cell-to-cell communication, synapses are the points at which communication occurs. The human brain has been estimated to contain 100 trillion synapses; the functions of these synapses are diverse: some are excitatory.
Sleep is a recurring state of mind and body, characterized by altered consciousness inhibited sensory activity, inhibition of nearly all voluntary muscles, reduced interactions with surroundings. It is distinguished from wakefulness by a decreased ability to react to stimuli, but more reactive than coma or disorders of consciousness, sleep displaying different and active brain patterns. Sleep occurs in repeating periods, in which the body alternates between two distinct modes: REM sleep and non-REM sleep. Although REM stands for "rapid eye movement", this mode of sleep has many other aspects, including virtual paralysis of the body. A well-known feature of sleep is the dream, an experience recounted in narrative form, which resembles waking life while in progress, but which can be distinguished as fantasy. During sleep, most of the body's systems are in an anabolic state, helping to restore the immune, nervous and muscular systems; the internal circadian clock promotes sleep daily at night. The diverse purposes and mechanisms of sleep are the subject of substantial ongoing research.
Sleep is a conserved behavior across animal evolution. Humans may suffer from various sleep disorders, including dyssomnias such as insomnia, hypersomnia and sleep apnea; the advent of artificial light has altered sleep timing in industrialized countries. The most pronounced physiological changes in sleep occur in the brain; the brain uses less energy during sleep than it does when awake during non-REM sleep. In areas with reduced activity, the brain restores its supply of adenosine triphosphate, the molecule used for short-term storage and transport of energy. In quiet waking, the brain is responsible for 20% of the body's energy use, thus this reduction has a noticeable effect on overall energy consumption. Sleep increases the sensory threshold. In other words, sleeping persons perceive fewer stimuli, but can still respond to loud noises and other salient sensory events. During slow-wave sleep, humans secrete bursts of growth hormone. All sleep during the day, is associated with secretion of prolactin.
Key physiological methods for monitoring and measuring changes during sleep include electroencephalography of brain waves, electrooculography of eye movements, electromyography of skeletal muscle activity. Simultaneous collection of these measurements is called polysomnography, can be performed in a specialized sleep laboratory. Sleep researchers use simplified electrocardiography for cardiac activity and actigraphy for motor movements. Sleep is divided into two broad types: non-rapid eye movement sleep and rapid eye movement sleep. Non-REM and REM sleep are so different that physiologists identify them as distinct behavioral states. Non-REM sleep after a transitional period is called slow-wave sleep or deep sleep. During this phase, body temperature and heart rate fall, the brain uses less energy. REM sleep known as paradoxical sleep, represents a smaller portion of total sleep time, it is the main occasion for dreams, is associated with desynchronized and fast brain waves, eye movements, loss of muscle tone, suspension of homeostasis.
The sleep cycle of alternate NREM and REM sleep takes an average of 90 minutes, occurring 4–6 times in a good night's sleep. The American Academy of Sleep Medicine divides NREM into three stages: N1, N2, N3, the last of, called delta sleep or slow-wave sleep; the whole period proceeds in the order: N1 → N2 → N3 → N2 → REM. REM sleep occurs as a person returns to stage 1 from a deep sleep. There is a greater amount of deep sleep earlier in the night, while the proportion of REM sleep increases in the two cycles just before natural awakening. Awakening can mean the end of sleep, or a moment to survey the environment and readjust body position before falling back asleep. Sleepers awaken soon after the end of a REM phase or sometimes in the middle of REM. Internal circadian indicators, along with successful reduction of homeostatic sleep need bring about awakening and the end of the sleep cycle. Awakening involves heightened electrical activation in the brain, beginning with the thalamus and spreading throughout the cortex.
During a night's sleep, a small amount of time is spent in a waking state. As measured by electroencephalography, young females are awake for 0–1% of the larger sleeping period. In adults, wakefulness increases in cycles. One study found 3% awake time in the first ninety-minute sleep cycle, 8% in the second, 10% in the third, 12% in the fourth, 13–14% in the fifth. Most of this awake time occurred shortly. Today, many humans wake up with an alarm clock. Many sleep quite differently on workdays versus days off, a pattern which can lead to chronic circadian desynchronization. Many people look at television and other screens before going to bed, a factor which may exacerbate disruption of the circadian cycle. Scientific studies on sleep have shown that sleep stage at awakening is an important factor in amplifying sleep inertia. Sleep timing is controlled by the circadian clock, sleep-wake homeostasis, to some extent by individual will. Sleep timing depends on hormo
Anger or wrath is an intense emotional state. It involves a strong hostile response to a perceived provocation, hurt or threat. A person experiencing anger will experience physical conditions, such as increased heart rate, elevated blood pressure, increased levels of adrenaline and noradrenaline; some view anger as an emotion which triggers part of the flight brain response. Anger is used as a protective mechanism to cover up hurt or sadness. Anger becomes the predominant feeling behaviorally and physiologically when a person makes the conscious choice to take action to stop the threatening behavior of another outside force; the English term comes from the term anger of Old Norse language. Anger can have many mental consequences; the external expression of anger can be found in facial expressions, body language, physiological responses, at times public acts of aggression. Facial expressions can range from inward angling of the eyebrows to a full frown. While most of those who experience anger explain its arousal as a result of "what has happened to them," psychologists point out that an angry person can well be mistaken because anger causes a loss in self-monitoring capacity and objective observability.
Modern psychologists view anger as a primary and mature emotion experienced by all humans at times, as something that has functional value for survival. Uncontrolled anger can, negatively affect personal or social well-being and impact negatively on those around them. While many philosophers and writers have warned against the spontaneous and uncontrolled fits of anger, there has been disagreement over the intrinsic value of anger; the issue of dealing with anger has been written about since the times of the earliest philosophers, but modern psychologists, in contrast to earlier writers, have pointed out the possible harmful effects of suppressing anger. Three types of anger are recognized by psychologists: Hasty and sudden anger is connected to the impulse for self-preservation, it is shared by human and other animals, it occurs when the animal is tormented or trapped. This form of anger is episodic. Settled and deliberate anger is a reaction to perceived deliberate harm or unfair treatment by others.
This form of anger is episodic. Dispositional anger is related more to character traits than to cognitions. Irritability and churlishness are examples of the last form of anger. Anger can mobilize psychological resources and boost determination toward correction of wrong behaviors, promotion of social justice, communication of negative sentiment, redress of grievances, it can facilitate patience. In contrast, anger can be destructive. Anger, in its strong form, impairs one's ability to process information and to exert cognitive control over their behavior. An angry person may lose his/her objectivity, prudence or thoughtfulness and may cause harm to themselves or others. There is a sharp distinction between anger and aggression though they mutually influence each other. While anger can activate aggression or increase its probability or intensity, it is neither a necessary nor a sufficient condition for aggression. Extension of the Stimuli of the Fighting Reactions. At the beginning of life the human infant struggles indiscriminately against any restraining force, whether it be another human being or a blanket which confines his movements.
There is no inherited susceptibility to social stimuli, as distinct from other stimulation, in anger. At a date the child learns that certain actions, such as striking and screaming, are effective toward persons, but not toward things. In adults, although the infantile response is still sometimes seen, the fighting reaction becomes well limited to stimuli whose hurting or restraining influence can be thrown off by physical violence. Raymond Novaco of University of California Irvine, who since 1975 has published a plethora of literature on the subject, stratified anger into three modalities: cognitive, somatic-affective, behavioral; the words annoyance and rage are imagined to be at opposite ends of an emotional continuum: mild irritation and annoyance at the low end and fury or murderous rage at the high end. Rage problems are conceptualized as "the inability to process emotions or life's experiences" either because the capacity to regulate emotion has never been sufficiently developed or because it has been temporarily lost due to more recent trauma.
Rage is understood as raw, undifferentiated emotions, that spill out when another life event that cannot be processed, no matter how trivial, puts more stress on the organism than it can bear. Anger, when viewed as a protective response or instinct to a perceived threat, is considered as positive; the negative expression of this state is known as aggression. Acting on this misplaced state is rage due to possible potential errors in judgment. Examples William DeFoore, an anger management writer, described anger as a pressure cooker: we can only apply pressure against our anger for a certain amount of time until it explodes. One simple dichotomy of anger expression is passive anger versus aggressive anger versus assertive anger; these three types of anger have some characteristic symptoms: Passive anger can be expressed in the following ways: Dispassion, such as giving someone the cold shoulder or a fake smile, looking unconcerned or "sitting on the fence" while others sort things out, dampening feelings with substance abuse, oversleeping, not responding to another's anger, f