User:Mfs2162/Affective neuroscience

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Affective neuroscience is the study of the how the brain processes emotions. This field combines neuroscience with the psychological study of personality, emotion, and mood. The basis of emotions and what emotions are remains an issue of debate within the field of affective neuroscience.

The term "affective neuroscience" was coined by neuroscientist Jaak Panksepp, at a time when cognitive neuroscience focused on parts of psychology that did not include emotion, such as attention or memory.

Ekman 60 faces task
The Ekman faces task is used to measure emotion recognition of six basic emotions. Black and white photographs of 10 actors (6 male, 4 female) are presented, with each actor displaying each emotion. Participants are usually asked to respond quickly with the name of the displayed emotion. The task is a common tool to study deficits in emotion regulation in patients with dementia, Parkinson's, and other cognitively degenerative disorders. The task has been used to analyze recognition errors in disorders such as borderline personality disorder, schizophrenia, and bipolar disorder.

Dot probe (emotion)
The emotional dot-probe paradigm is a task used to assess selective visual attention to and failure to detach attention from affective stimuli. The paradigm begins with a fixation cross at the center of a screen. An emotional stimulus and a neutral stimulus appear side by side, after which a dot appears behind either the neutral stimulus (incongruent condition) or the affective stimulus (congruent condition). Participants are asked to indicate when they see this dot, and response latency is measured. Dots that appear on the same side of the screen as the image the participant was looking at will be identified more quickly. Thus, it is possible to discern which object the participant was attending to by subtracting the reaction time to respond to congruent versus incongruent trials.

The best documented research with the dot probe paradigm involves attention to threat related stimuli, such as fearful faces, in individuals with anxiety disorders. Anxious individuals tend to respond more quickly to congruent trials, which may indicate vigilance to threat and/or failure to detach attention from threatening stimuli. A specificity effect of attention has also been noted, with individuals attending selectively to threats related to their particular disorder. For example, those with social phobia selectively attend to social threats but not physical threats. However, this specificity may be even more nuanced. Participants with obsessive-compulsive disorder symptoms initially show attentional bias to compulsive threat, but this bias is attenuated in later trials due to habituation to the threat stimuli.

Fear potentiated startle
Fear-potentiated startle (FPS) has been utilized as a psychophysiological index of fear reaction in both animals and humans. FPS is most often assessed through the magnitude of the eyeblink startle reflex, which can be measured by electromyography. This eyeblink reflex is an automatic defensive reaction to an abrupt elicitor, making it an objective indicator of fear. Typical FPS paradigms involve bursts of noise or abrupt flashes of light transmitted while an individual attends to a set of stimuli. Startle reflexes have been shown to be modulated by emotion. For example, healthy participants tend to show enhanced startle responses while viewing negatively valenced images and attenuated startle while viewing positively valenced images, as compared with neutral images.

The startle response to a particular stimulus is greater under conditions of threat. A common example given to indicate this phenomenon is that one's startle response to a flash of light will be greater when walking in a dangerous neighborhood at night than it would under safer conditions. In laboratory studies, the threat of receiving shock is enough to potentiate startle, even without any actual shock.

Fear potentiated startle paradigms are often used to study fear learning and extinction in individuals with post-traumatic stress disorder (PTSD) and other anxiety disorders. In fear conditioning studies, an initially neutral stimulus is repeatedly paired with an aversive one, borrowing from classical conditioning. FPS studies have demonstrated that PTSD patients have enhanced startle responses during both danger cues and neutral/safety cues as compared with healthy participants.