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The startle response is an unconscious defensive response to sudden or threatening stimuli.
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Ethology is the scientific and objective study of animal behaviour, usually with a focus on behaviour under natural conditions, and viewing behaviour as an evolutionarily adaptive trait. Behaviourism as a term also describes the scientific and objective study of animal behaviour, usually referring to measured responses to stimuli or to trained behavioural responses in a laboratory context, without a particular emphasis on evolutionary adaptivity. Throughout history, different naturalists have studied aspects of animal behaviour. Ethology has its scientific roots in the work of Charles Darwin (1809-1882) and of American and German ornithologists of the late 19th and early 20th century, including Charles O. Whitman, Oskar Heinroth (1871-1945), and Wallace Craig. The modern discipline of ethology is generally considered to have begun during the 1930s with the work of Dutch biologist Nikolaas Tinbergen (1907-1988) and of Austrian biologists Konrad Lorenz and Karl von Frisch (1886-1982), the three recipients of the 1973 Nobel Prize in Physiology or Medicine. Ethology combines laboratory and field science, with a strong relation to some other disciplines such as neuroanatomy, ecology, and evolutionary biology. Ethologists typically show interest in a behavioural process rather than in a particular animal group, and often study one type of behaviour, such as aggression, in a number of unrelated species.
A phobia is a type of anxiety disorder defined by a persistent and excessive fear of an object or situation. The phobia typically results in a rapid onset of fear and is present for more than six months. The affected person goes to great lengths to avoid the situation or object, to a degree greater than the actual danger posed. If the feared object or situation cannot be avoided, the affected person experiences significant distress. With blood or injury phobia, fainting may occur. Agoraphobia is often associated with panic attacks. Usually a person has phobias to a number of objects or situations.
Nikolaas "Niko" Tinbergen was a Dutch biologist and ornithologist who shared the 1973 Nobel Prize in Physiology or Medicine with Karl von Frisch and Konrad Lorenz for their discoveries concerning organization and elicitation of individual and social behavior patterns in animals. He is regarded as one of the founders of modern ethology, the study of animal behavior.
The experimental analysis of behavior is school of thought in psychology founded on B. F. Skinner's philosophy of radical behaviorism and defines the basic principles used in applied behavior analysis. A central principle was the inductive reasoning data-driven examination of functional relations, as opposed to the kinds of hypothetico-deductive learning theory that had grown up in the comparative psychology of the 1920–1950 period. Skinner's approach was characterized by observation of measurable behavior which could be predicted and controlled. It owed its early success to the effectiveness of Skinner's procedures of operant conditioning, both in the laboratory and in behavior therapy.
A reflex, or reflex action, is an involuntary and nearly instantaneous movement in response to a stimulus. A reflex is made possible by neural pathways called reflex arcs which can act on an impulse before that impulse reaches the brain. The reflex is then an automatic response to a stimulus that does not receive or need conscious thought.
A supernormal stimulus or superstimulus is an exaggerated version of a stimulus to which there is an existing response tendency, or any stimulus that elicits a response more strongly than the stimulus for which it evolved.
Psychophysics quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they produce. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of perceptual processes by studying the effect on a subject's experience or behaviour of systematically varying the properties of a stimulus along one or more physical dimensions".
A taxis is the movement of an organism in response to a stimulus such as light or the presence of food. Taxes are innate behavioural responses. A taxis differs from a tropism in that in the case of taxis, the organism has motility and demonstrates guided movement towards or away from the stimulus source. It is sometimes distinguished from a kinesis, a non-directional change in activity in response to a stimulus.
In animals, including humans, the startle response is a largely unconscious defensive response to sudden or threatening stimuli, such as sudden noise or sharp movement, and is associated with negative affect. Usually the onset of the startle response is a startle reflex reaction. The startle reflex is a brainstem reflectory reaction (reflex) that serves to protect vulnerable parts, such as the back of the neck and the eyes (eyeblink) and facilitates escape from sudden stimuli. It is found across the lifespan of many species. A variety of responses may occur because of individual's emotional state, body posture, preparation for execution of a motor task, or other activities. The startle response is implicated in the formation of specific phobias.
Affective neuroscience is the study of the neural mechanisms of emotion. This interdisciplinary field combines neuroscience with the psychological study of personality, emotion, and mood. The putative existence of 'basic emotions' and their defining attributes represents a long lasting and yet unsettled issue in psychology.
Prepulse inhibition (PPI) is a neurological phenomenon in which a weaker prestimulus (prepulse) inhibits the reaction of an organism to a subsequent strong reflex-eliciting stimulus (pulse), often using the startle reflex. The stimuli are usually acoustic, but tactile stimuli and light stimuli are also used. When prepulse inhibition is high, the corresponding one-time startle response is reduced.
Sensory neuroscience is a subfield of neuroscience which explores the anatomy and physiology of neurons that are part of sensory systems such as vision, hearing, and olfaction. Neurons in sensory regions of the brain respond to stimuli by firing one or more nerve impulses following stimulus presentation. How is information about the outside world encoded by the rate, timing, and pattern of action potentials? This so-called neural code is currently poorly understood and sensory neuroscience plays an important role in the attempt to decipher it. Looking at early sensory processing is advantageous since brain regions that are "higher up" contain neurons which encode more abstract representations. However, the hope is that there are unifying principles which govern how the brain encodes and processes information. Studying sensory systems is an important stepping stone in our understanding of brain function in general.
In animal behaviour, escape response, escape reaction, or escape behaviour is a rapid series of movements performed by an animal in response to possible predation. Some types of escape response may include camouflage, freezing behaviour, and fleeing, among others It is an anti-predator behaviour that varies from species to species. In fact, variation between individuals is linked to increased survival. In addition, it is not merely increased speed that contributes to the success of the escape response; other factors, including reaction time and the individual's context can play a role. The individual escape response of a particular animal can vary based on an animal's previous experience and current state
Surprise is a brief mental and physiological state, a startle response experienced by animals and humans as the result of an unexpected event. Surprise can have any valence; that is, it can be neutral/moderate, pleasant, unpleasant, positive, or negative. Surprise can occur in varying levels of intensity ranging from very-surprised, which may induce the fight-or-flight response, or little-surprise that elicits a less intense response to the stimuli.
Fetal movement refers to motion of a fetus caused by its own muscle activity. Locomotor activity begins during the late embryological stage and changes in nature throughout development. Muscles begin to move as soon as they are innervated. These first movements are not reflexive, but arise from self-generated nerve impulses originating in the spinal cord. As the nervous system matures, muscles can move in response to stimuli.
The Mauthner cells are a pair of big and easily identifiable neurons located in the rhombomere 4 of the hindbrain in fish and amphibians that are responsible for a very fast escape reflex. The cells are also notable for their unusual use of both chemical and electrical synapses.
Whether fish feel pain similar to humans or differently is a contentious issue. Pain is a complex mental state, with a distinct perceptual quality but also associated with suffering, which is an emotional state. Because of this complexity, the presence of pain in an animal, or another human for that matter, cannot be determined unambiguously using observational methods, but the conclusion that animals experience pain is often inferred on the basis of likely presence of phenomenal consciousness which is deduced from comparative brain physiology as well as physical and behavioural reactions.
The question of whether crustaceans experience pain is a matter of scientific debate. Pain is a complex mental state, with a distinct perceptual quality but also associated with suffering, which is an emotional state. Because of this complexity, the presence of pain in an animal, or another human for that matter, cannot be determined unambiguously using observational methods, but the conclusion that animals experience pain is often inferred on the basis of likely presence of phenomenal consciousness which is deduced from comparative brain physiology as well as physical and behavioural reactions.
Pain in invertebrates is a contentious issue. Although there are numerous definitions of pain, almost all involve two key components. First, nociception is required. This is the ability to detect noxious stimuli which evokes a reflex response that moves the entire animal, or the affected part of its body, away from the source of the stimulus. The concept of nociception does not imply any adverse, subjective feeling; it is a reflex action. The second component is the experience of "pain" itself, or suffering—i.e., the internal, emotional interpretation of the nociceptive experience. Pain is therefore a private, emotional experience. Pain cannot be directly measured in other animals, including other humans; responses to putatively painful stimuli can be measured, but not the experience itself. To address this problem when assessing the capacity of other species to experience pain, argument-by-analogy is used. This is based on the principle that if a non-human animal's responses to stimuli are similar to those of humans, it is likely to have had an analogous experience. It has been argued that if a pin is stuck in a chimpanzee's finger and they rapidly withdraw their hand, then argument-by-analogy implies that like humans, they felt pain. It has been questioned why the inference does not then follow that a cockroach experiences pain when it writhes after being stuck with a pin. This argument-by-analogy approach to the concept of pain in invertebrates has been followed by others.
Fear-potentiated startle (FPS) is a reflexive physiological reaction to a presented stimulus, and is an indicator of the fear reaction in an organism. The FPS response can be elicited in the face of any threatening stimulus, but it can also be elicited by a neutral stimulus as a result of fear conditioning, a process that occurs when a benign stimulus comes to evoke fear and anxiety upon being paired with a traumatic or fear-provoking event. The stimulus in question is usually of auditory or visual nature, and startle response measures include eyeblink rates and pulse/heart rate. The negative impact of heightened FPS in the face of neutral stimuli can be treated pharmacologically, using psychotropic medications that are typically used to reduce anxiety in humans. Recent literature, moreover, has implicated increased FPS responses as a correlate in posttraumatic stress disorder (PTSD) and other anxiety disorders.