Abstract
The present study consists in verify the habituation effect comparing different moments of presentations, repeatedly, through pictures of International Affective Picture System -IAPS- of Lang and Col. Come in stimulus activators (aversive and appetitive) and of stimulus neutral. Search itself verify by the response physiological of the Galvanic Skin Response (GSR) and for the heart Beating (HR) realize in laboratory by the exhibition of IAPS's Pictures for the Habituation paradigm to compare between first presentation and the Fifth presentation. Some theories defend a reduction of the GSR and HR giving itself the Habituation effect. In this accomplished study to a sample of ten subjects are not statistically significant differences in GSR's response and HR to stimulus neutral, giving itself habituation. However there are significant differences in stimulus activators, and the effect Habituation does not accomplish in the response HR, there be sensitization effects.
Words-key: Emotions, Galvanic Skin Response (GSR), Habituation, Heart beat (HR), IAPS.
Different emotion-arousing stimuli elicit types of emotional responses. Heart rate decelerates while viewing unpleasant pictures, yet accelerates during unpleasant mental imagery (Lang et al., 1990, cit in). Habituation effect being a decrease in responding and a sensitization effect being an increase in responding (cit. in DOMJAN, The principles of learning and behavior, 1998).
The present study verify the habituation effect comparing different moments of presentations, repeatedly, through pictures of International Affective Picture System -IAPS- of Lang and Col. Come in stimulus activators (aversive and appetitive) and of stimulus neutral. Search itself verify by the response physiological of the Galvanic Skin Response (GSR) and for the heart Beating (HR) realize in laboratory by the exhibition of IAPS's Pictures for the Habituation paradigm to compare between first presentation and the Fifth presentation.
“The International Affective Picture System (IAPS) is being developed to provide a set of normative emotional stimuli for experimental investigations of emotion and attention” (cit. in Lang and col. In IAPS Tecn. Manual, 2005). “Criteria for pictures included in the IAPS include: 1) Selection of a broad sample of contents across the entire affective space. 2) All pictures are in color, 3) Pictures are selected that are easy to resolve, have clear figure - ground relationships, and communicate affective quality relatively quickly” (cit. in Lang and col. In IAPS Tecn. Manual, 2005). The psychophysiology of emotional perception has been studied by researchers using a set of standard photographic picture stimuli calibrated for affective response. There are currently over 700 pictures in the International Affective Picture System (IAPS; Lang, Bradley, & Cuthbert, 1998), and each picture is rated for experienced pleasure and arousal by a large normative subject sample (cit. in Handbook). The split-half coefficients for the valence and arousal dimensions were highly reliable (p< .001) (cit. in Lang and col. In IAPS, Tecn. Manual, 2005). Independent sample t-tests of these replicate pictures (which were distributed widely in the affective space) revealed no significant difference in either the mean valence or the mean arousal ratings (cit. in Lang and col. Cit in IAPS Tecn. Manual, 2005).
The intensity of an emotion generated by a picture depends not only on the particular item (e.g., chainsaw Cit. in the handbook) but also on the content of the as well as on the history of the person viewing the picture. Skin conductance changes are more closely correlated with arousal ratings in males than in females (Lang, Greenwald, Bradley, & Hamm, 1993 cit. in the handbook of psychology, 2003). Heart rate decelerates while viewing unpleasant pictures, yet accelerates during unpleasant mental imagery (Lang et al., 1990). When the same stimulus is constantly several times presented, generally there is one strong answer to the first presentation and a decreased answer to each presentation subsequent, until do not there be any more any measurable answer. This process is called habituation (Zuckerman, 1990). When people are first exposed to a new picture, reaction time responses to probes are significantly slower for emotionally arousing than for affectively calm pictures (Bradley, Greenwald, Petry, & Lang, 1992 cit. in the Handbook, 2003).
Habituation
If we had to respond to all the stimuli in the environment it will be chaotic, habituation can help us to ignore some stimuli and sensitization can provide to select what to respond to. This is a matter of surviving and an evolutionary process (cit. in DOMJAN, The principles of learning and behavior, 1998).
Habituation effects are technically referred to a responsiveness decreases produced by repeated stimulation. And increases in responsiveness are called sensitization effects. A simple reflex response does not occur the same way each time (Bashinski, Werner and Rudy, 1985, cit. in Mazur, Learning and behavior, 1998). The nature of the change is determined by the nature of the stimulus. The results of some experiment show that the visual attention, repeated elicitation of the startle reflex produced a decrease in the magnitude of the startle reaction n one situation and an increase under other circumstances (cit. in DOMJAN, The principles of learning and behavior, 1998). A reflex consists of three components; first, a stimulus activates one of the sense organs such the eyes or ears. These generate sensory neural impulses that are relayed to the central nervous system. The second component involves relay of the sensory messages trough interneuron’s to motor nerves and finally, the neural impulses in motor nerves in turn activate the muscles that create the active response (cit. in Mazur, Learning and behavior, 1998). In this process another system are activate for a more responsible response to the situation, like de heart biting and the Galvanic Skin Response in many others. By repeated stimulation can occurs sensory adaptation. The Dual-Process theory proposed by Groves and Thompson, 1970 (cit. in DOMJAN, The principles of learning and behavior, 1998) assumes that different types of underlying neutral process are responsible for increases and decreases in responsiveness.
Emotions
The words emotion and motivation are both derived from the Latin word for move: movere. In fact, the behavior of a simple organism such as a flatworm can be characterized almost entirely by two survival movements: direct approach to appetitive stimuli and withdrawal from aversive stimuli (Schneirla, 1959 cit. in Handbook).
We can tell about the emotions that they are feeling that generally have psychological and cognitive elements and that influence the behavior (cit. In; Understand the Psychology de R. Feldman, 2001). The emotions have such an important paper in our everyday. They can prepare us for action, mould our future behavior and help us to regulate our social interaction (Schere, 1994; Averill, 1994; Oatley and Jenkins, 1996; Cit in Understand the Psychology of R. Feldman, 2001). A series of physiologic alterations accompany the emotions. Some develop approaches are the James-Lange's Theories (1890); Cannon-Bard (1924) and Schacter-Singer (1960) (cit. In Gleitman, 2005). Some studies suggest that emotional knowledge is hierarchically organized and that the super ordinate division is between positivity (pleasant states: love, joy) and negativity (unpleasant states: anger, sadness, fear). Using the semantic differential, Osgood and his associates (e.g., Osgood, Suci, & Tannenbaum, 1957 cit. in Handbook) showed that emotional descriptors were primarily distributed along a bipolar dimension of affective valence-ranging from attraction and pleasure to aversion and displeasure. A dimension of activation -from calm to arouse- also accounted for substantial variance.
Some theoretical suggest that there are specific corporeal reaction that cause experimentation and determined our emotion - we have fear because our heart beats - and for contrast other suggest that physiologic reaction are the result of emotion experimentation - it is the fear that causes the beating of heart increase (cit. In Gleitman, 2005). James-Lange's Theory (William James and Carl Lange, 1890, cit. In Feldman, 2001), According to them the emotional experience is just a reaction to the instinctive corporeal happenings that occur in response to a situation or happening of the half. The brain interprets the visceral changes of the body as it tries an emotional state. Other great relevance theory is the one of Cannon-Bard (1929), and it bases itself on belief that so much for activation physiologic as the emotional are simultaneously produced by the nervous pulse (cit. In Feldman, 2001). And, yet, Schachter-Singer's Theory (1960), in this theory it believes that the emotions are determined jointly for a specific kind of activation physiologic and that its interpretation can be based in the middle involutes of form to determine exactly what we are to try.
The advances in the measures of the nervous system and of other parts of the body have allowing the investigation advances with more care, more minutely, every time exist more data on the association between activation biological and the involved emotions ( Davidson, 1994 Levenson,1994; Cit. In Understand the Psychology of R. Feldman, 2001).
GSR (Galvanic Skin Response) is electronic equipment that acts as relaxation response monitor. Through two electrodes applied metallic in hands fingers, register and amplifies the skin galvanic resistance alterations to the ticket of a current very little electricity. This is converted in visual indication by means of analogical and audible meter, through a tone, of variable rhythm, emitted by a small phone (cit. in Handbook). The skin galvanic answer effect has its origin in activity of the sweat glands. These glands, they are under control it of the SNS, that is a part of the SNA. This system it resembles to a threads complex outline that transport pulses for all the body organs. (cit. In Gleitman, 2005). Whenever a person is frightened or excited, for any reason, even though lightly, the nice nervous system respond active the physical and chemical mechanisms through the body, including the sweat glands. In spite of this answer not always to be visible (sweat), of the itself, for norm, a skin resistance alteration. Therefore, if an individual be excited, the galvanic resistance of the low skin producing a climb in the rhythm and in the tone emitted by the device. On the other hand when it is calm and relaxed, the skin resistance increases, producing a rhythm and tone lowering emitted by the device. The latency of the response may vary from one to three seconds (cit in Guyton e Hall; Traded of Physiology)
HR – (Heart beat)
The heart rate adapts to changes in the body. The neurological regulation of the circulation acts like complement of the local control of the sanguine flow. The autonomous nervous system is fundamental in the regulation of the arterial pressure,
The heart owns a system specialized for the generation of rhythmical pulses that produce the excitation (cit in Guyton e Hall; Traded of Physiology). As the cardiac pulse propagates through the heart, the electric chains spread by the fabrics that circle it and a small proportion propagates until the body surface. When putting electrodes on the skin, in opposite sides of the heart, the electric potentials generated by these current can be registered. That record is known as electrocardiogram (ECG). Heart rate is the highest number of times your heart can contract in one minute. HR is used as a base number to calculate target heart rate for exercise. The average adult heart beats about 60 to 100 times a minute at rest (cit in Wikipedia).
The amygdale is directly association with the activation of the respond system, many cells in the amygdale, “leading to a large release of neurochemicals and strong activation of the defense motivation system. Similar amygdala activations can be assumed to occur when we think about an unpleasant experience or look at emotional pictures” (cit. in the Handbook of psychology, 2003).
Neutral and active stimulation
The initial reaction to stimulation involves many sub reflexes. In reacting to visual input, and it will be accompanying with a vascular and cardiac changes. If the input has no motivational relevance, the initial attention response soon the initial habituates. (Cit. in Handbook of psychology, 2003) “Cues of appetite or aversion, on the other hand, lead to more sustained, singular patterns of attentional processing”.
Emotion involves multiple responses, organized according to temporal and spatial parameters. Thus, events that are positive-appetitive or aversive-threatening engage attention (cit. in Handbook of psychology, Volume 3, 2003). Motive cues also occasion metabolic arousal, anticipatory responses that are oriented towards the engaging event. Many theorists agree that feedback from bodily or physiological activity contributes to emotion activation. There is disagreement as to what kind of feedback is important. Some think that it is visceral feedback or feedback from the activity of the smooth-muscle organs innervated by the autonomic nervous system (ANS), such as the stomach and heart (cit in Izard, The structure and functions of emotions) Affective arousal reflects motivational mobilization, appetitive or defensive, modulated by changes in survival need or in the probability of nocive or appetitive consummation (cit. in Handbook of psychology, 2003).
Lang (1994) (cit. in Handbook of psychology, 2003) suggested that emotional memories may be considered network who include associated information about emotional episodes, coding stimulus events and context, behavior, and interpretive elaborations.
The Startle Reflex is very important to the affective reaction (Cit. in Damásio, Espinosa, 2003). There is a startle inhibition during pleasant stimuli and potentiation when pictures were judged to be unpleasant: The largest startle blink responses occurred during unpleasant content and the smallest during pleasant pictures (e.g, Lang, 1995; Lang et al., 1990; Vrana, Spence, & Lang, 1988; and see Bradley, 2000, cit. in the Handbook of psychology, 2003). Startle magnitude then increases progressively with reported arousal, and the strongest potentiation occur during viewing of the most arousing unpleasant stimuli (Cuthbert et al., 1996). In contrast, the most pleasantly arousing percepts show the largest probe startle inhibition.
The intensity of an emotion generated by a picture depends not only on the particular item (e.g., chainsaw Cit. in the handbook of psychology, Volume 3, 2003) but also on the content of the as well as on the history of the person viewing the picture. “the increased vigilance in the post encounter period is characterized by a progressive augmentation of physiological indexes of attention—greater skin conductance, increased heart rate deceleration, and inhibition of the probe startle reflex when arousal is still relatively low” ( cit. in the handbook, 2003). Voluntary attention may often be directed to emotional stimuli given their importance for survival, reproduction, and procreation. emotion potentiated attention effects specifically during later stages of processing. These findings suggest specifying the interaction of attention and emotion in distinct processing stages. (Schupp H.T. & col.; Selective Visual Attention to Emotion, Cit in the Journal of Neuroscience, January 31, 2007 • 27(5):1082–1089). “Activity in extra striate visual cortex is greater when people view emotional relative to neutral pictures. Prior brain imaging and psychophysiological work has further suggested a bias for men to react more strongly to pleasant pictures, and for women to react more strongly to unpleasant pictures” (cit in Affective Picture Perception: gender differences in visual cortex; Sabatinelli D., Flaisch T., Bradley M. , Fitzsimmons J. R. and Lang P.L.2004; http://www.neuroport.com/).
“The IAPS has been used to provide abundant insight into the dimensional aspects of emotion. For instance, heart rate and facial electromyographic activity differentiate negative from positive valence, whereas skin conductance increases with increased arousal” (Bradley & Lang, 2000; Lang, Bradley, & Cuthbert, 1998 cit in http://www.pubmedcentral.nih.gov/articlerender). When the subjects imagine the activation of response as the cardiac rhythm, which can carry directly to the activation of this same system (Lang, 1984 cit. In Cognitive Psychology, 1997). Skin conductance changes are more closely correlated with arousal ratings in males than in females (Lang, Greenwald, Bradley, & Hamm, 1993 cit. in the handbook of psychology, 2003). Heart rate decelerates while viewing unpleasant pictures, yet accelerates during unpleasant mental imagery (Lang et al., 1990).
The present study verify the habituation effect comparing different moments of presentations, repeatedly, through pictures of International Affective Picture System -IAPS- of Lang and Col. Come in stimulus activators (aversive and appetitive) and of stimulus neutral. Search itself verify by the response physiological of the Galvanic Skin Response (GSR) and for the heart Beating (HR) realize in laboratory by the exhibition of IAPS's Pictures for the Habituation paradigm to compare between first presentation and the Fifth presentation.
Material, Method, Results and Discussion.
Selection of participants, sessions structuring, electrodes location and for selection of the images.. It presents enclosed the chosen and presented pictures and according to IAPS his respective values affective, arousal and dominance for all the subjects. In the selection of participants has to if it has in account the inclusion and exclusion criteria and demographic characteristics, age and sex. Regarding the subjects the sample dimension belongs to ten subjects being five masculine, four feminine and one of unknown son-in-law. To verify if rácio was fitting to IAPS's Criteria, 1:2, was used Qui-Square of Adjustment, enclosed....
For the selection of the images will allow inducing the emotional state to allow to gathers of the data biometrics.
The Age presents an average=29,87 and DP=1,05, with an age minima 19 year and maximum 46 year. It was utilized the K-S to verify there is a normal distribution, what we verify by the value of p=0,722.
It intends in this study evaluate for existence of Habituation by the comparison and observation between 1st and the 5th presentation, see in the slide show with contends of the pictures of IAPS, 14 neutral and 8 activators, measuring for reaction physiological by GSR's Answer and HR.
It used the K-S test to verify if the distribution is normal for all variaveis to observe, with the next results: Hr_1ªap_Neu-P=0,919; Hr_5ªap_Neu-P=0,967; Hr_1ap_act-P=0,723; Hr_5ap_act-P=0,698; GSR_1ªap_Neu-P=0,995; GSR_5ªap_Neu-P=0,987; GSR_1ªap_act-P=1,00; GSR_5ªap_act-P=0,944. All the distributions are normal then go to Parametric Paired Samples t Test to compare the averages, verify if there are or not statistically significant differences and the correlation between both moments. Thus search itself verify if gave habituation in stimulus neutral and activators visualization between first and the fifth moment by GSR's Reading and HR.
What jumps to seen by the observation of the analyzes is that for stimulus neutral there are not statistically significant differences between 1st and the 5th presentation wants in the GSR's Measures as in HR. But in the exhibition stimulus activators photos (aversive/appetitive) there are statistically significant differences for the comparison between 1st and 5th presentation for GSR and HR.
Conclusion
The nature of the change is determined by the nature of the stimulus but can involve many others influent process. The Dual-Process theory proposed by Groves and Thompson, 1970 (cit. in DOMJAN, The principles of learning and behavior, 1998) assumes that different types of underlying neutral process are responsible for increases and decreases in responsiveness. Habituation effects are technically referred to a responsiveness decreases produced by repeated stimulation. And increases in responsiveness are called sensitization effects. The biological model of emotion presented here suggests that, depending on level of stimulus aversion (threat, apprehension); patterns of physiological change (and in humans, reports of experienced emotional arousal) will systematically vary with the level of defense system activation. When the subjects imagine the activation of answers as the cardiac rhythm, which can carry directly to the activation of this same system (Lang, 1984 cit. In Cognitive Psychology, 1997). “The data are consistent with the view that reported affective experience is determined in significant part by the individual’s motivational state. That is, negative affective valence (unpleasant feelings) is associated with activation of the defense system; positive valence (pleasant feelings) is associated with activation of the appetitive system. Reports of arousal are associated with both states, reflecting an increase in incentive strength and organism mobilization” (cit. in the handbook, 2003).
In the ten subjects of this study we don’t found statistically significant differences in GSR's response and HR to stimulus neutral, giving itself habituation. However there are significant differences in stimulus activators, and the effect Habituation does not accomplish in the response HR, there be sensitization effects.
Álvaro Augusto dos Santos Carvalho
