LOW EMOTIONAL AROUSAL IN DEPRESSION AS EXPLAINED BY THE MOTIVATED ATTENTION APPROACH (La baja activación emocional en la depresión explicada por el enfoque de la atención motivada)

Stephan Moratti

Description

Abstract
Depression has been associated with low emotional arousal. Highly arousing emotional stimuli engage the cortical circuits related to the allocation of attention towards these stimuli. Thus, it has been hypothesized that depression could be characterized by a deficit in these brain circuits. This brief review summarizes how attention and emotion are interconnected and suggests that common brain mechanisms underlie the link between emotion and attention. Finally, the results from depression research are presented that show that low emotional arousal in depression could arise from a deficit in brain circuits related to attention.
Resumen
La depresión se ha asociado con baja activación emocional. Los estímulos emocionales de alta activación involucran circuitos corticales que son relevantes para la dirección de la atención hacia estos estímulos. Por lo tanto, se ha planteado la hipótesis de que la depresión podría ser caracterizada por un déficit en estos circuitos cerebrales. Esta breve revisión resume como la atención y la emoción están interrelacionados y sugiere que existen mecanismos cerebrales de la emoción y la atención comunes. Por último, se presentan los resultados de una investigación de la depresión, que demuestra que la excitación emocional baja en la depresión podría surgir de un déficit en los circuitos cerebrales de la atención.

Sujets

• Dépression
• Émotion
• Attention
• Depresión
• Emoción
• Atención

Informations

• Publié par: erevistas
• Publié le: 01 janvier 2012
• Nombre de lectures: 16
• Langue: Español

Extrait

Escritos de Psicología, Vol. 5, nº 2, pp. 20-26 Copyright © 2012 Escritos de Psicología
Mayo-Agosto 2012 ISSN 1989-3809 DOI: 10.5231/psy.writ.2012.1106
Low emotional arousal in depression as explained by the motivated
attention approach
La baja activación emocional en la depresión explicada por el
enfoque de la atención motivada
Stephan Moratti, PhD
Departamento de Psicología Básica I. Universidad Complutense de Madrid, España.
Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, España.
Disponible online 31 de agosto de 2012
Depression has been associated with low emotional arousal. Highly arousing emotional stimuli engage the cortical
circuits related to the allocation of attention towards these stimuli. Thus, it has been hypothesized that depression
could be characterized by a defcit in these brain circuits. This brief review summarizes how attention and emotion are
interconnected and suggests that common brain mechanisms underlie the link between emotion and attention. Finally,
the results from depression research are presented that show that low emotional arousal in depression could arise from
a defcit in brain circuits related to attention.
Keywords: Depression; Emotion; Attention; Fronto-parietal cortex.
La depresión se ha asociado con baja activación emocional. Los estímulos emocionales de alta activación involucran
circuitos corticales que son relevantes para la dirección de la atención hacia estos estímulos. Por lo tanto, se ha plan-
teado la hipótesis de que la depresión podría ser caracterizada por un défcit en estos circuitos cerebrales. Esta breve
revisión resume como la atención y la emoción están interrelacionados y sugiere que existen mecanismos cerebrales
de la emoción y la atención comunes. Por último, se presentan los resultados de una investigación de la depresión,
que demuestra que la excitación emocional baja en la depresión podría surgir de un défcit en los circuitos cerebrales
de la atención.
Palabras Clave: Depresión; Emoción; Atención; Corteza fronto-parietal.
Correspondence concerning this article should be addressed to: Stephan Moratti, Universidad Complutense de Madrid, Departamento de Psicología
Básica I, 28223 Pozuelo de Alarcón (Madrid), España. E-mail: [e-mail]
This brief review has been motivated by a talk given at the “II Jornada de Neurociencia Afectiva: Avances en el estudio de la depresión”, 2011 in
Malaga, Spain.
20LOW EMOTIONAL AROUSAL IN DEPRESSION
One of the main characteristics of depression is disturbed increased skin conductance responses compared to neutral
processing of emotional information as indexed by images. However, when presented for the frst time,
startle refex modulation during emotional stimuli and facial stimuli also provoked skin conductance changes different from
expression (Forbes, Miller, Cohn, Fox & Kovacs, 2005; Geh- zero. Nevertheless, when the same pictures were shown to the
ricke & Shapiro, 2000). Low engagement of arousal related same participants one week later, only emotional pictures elic-
brain structures during emotional information processing has ited increased physiological arousal.
been associated with anhedonia and blunted affect in depres- Attention allocation towards emotional high arousing
sive disorders (Heller & Nitschke, 1997). In healthy persons stimuli can be also observed on the behavioral level. When
automatic attention allocation towards emotional high arous- participants have to detect fear relevant stimuli such as snakes
ing stimuli like emotional pictures or words has been associ- or spiders within many fear irrelevant distractors, they are
ated with motivated attention (Bradley, 2009; Lang, Bradley much faster than vice versa (Öhman et al., 2001). This effect
& Cuthbert, 1997). Motivated attention is a concept that has is augmented when subjects suffer from phobias of snakes or
been introduced by researchers which have emphasized that spiders indicating that increasing the motivational relevance of
high arousing stimuli, motivationally relevant for the indi- the stimuli boosts automatic attention allocation. Thus, it can
vidual, engage orienting responses (Bradley, 2009). These be concluded that emotion drives natural selective attention
responses are refected in (1) behavioral measures of attention (Öhman et al., 2001).
(Öhman, Flykt, & Esteves, 2001), (2) changes of autonomous Another strategy to link attention and emotion with respect
nervous system activity such as heart rate deceleration or skin to brain responses is to compare the cortical processing of
conductance increases (Bradley, Codispoti, Cuthbert & Lang, stimuli that do not bear any emotional signifcance but have to
2001), and (3) central nervous activity in attention related brain be attended with the cortical processing of emotional stimuli.
structures (Moratti, Keil & Stolarova, 2004; Moratti, Saugar If similar effects can be observed one can infer that the brain
& Strange, 2011). This line of research has a long tradition is using at least partly overlapping brain mechanism for emo-
and the processes involved are well studied although some tion and attention. For example it has been shown that neu-
issues are still under debate. Therefore, the motivated attention rons discharge preferentially for different objects within the
approach offers a profound framework for studying patholo- ventromedial temporal cortex in monkeys (Chelazzi, Duncan,
gies associated with emotion processing disturbances such Miller & Desimone, 1998). However, increased neuronal fring
as depression. In the present brief overview we frst present rates for a preferred object can only be observed over a longer
some basic foundations of the motivated attention approach time period if the monkey directs its attention to that object
and related brain structures and second present results that (Chelazzi et al., 1998). Thus, cortical processing within special-
associate depression with defcits in attention relevant brain ized brain regions that code specifc objects is enhanced when
structures. the corresponding objects are attended. Humans and monkeys
also have specialized brain areas (in humans fusiform face area;
Attention and emotion FFA) for face processing (Kanwisher & Yovel, 2006; Sugase,
The orienting response (OR) is associated with the auto- Yamane, Ueno & Kawano, 1999). In monkeys, neuronal fring
matic detection of novel stimuli in our environment because rates in temporal cortex are increased and prolonged when the
novel stimuli bear signifcance for the reorganization of the facial expression is emotional (Sugase et al., 1999). In humans,
organism’s ongoing behavior. As our capacity of stimulus pro- hemodynamic responses are increased in the FFA when emo-
cessing is limited and the environment is full of many stim- tional faces are shown (Vuilleumier, Armony, Driver & Dolan,
uli, we have to flter somehow the important environmental 2001). Neutral meaningless gray gratings without any signif -
cues. Attention allocation during an OR towards a specifc cance for the individual provoke increased activity in occipi-
stimulus serves this function. The attention processes related tal cortex after having been paired with an aversive loud noise
to the OR have been associated with physiological arousal. A (Moratti & Keil, 2009). The enhanced visual processing after
classical measure of the OR is the sympathetically mediated learning occurs independently of conscious expectancy of the
skin conductance response (Critchley, 2002). Skin conduc- aversive stimuli (Moratti & Keil, 2009). Angry prosody of
tance increases for novel stimuli (Venables & Cristie, 1980). meaningless speech stimuli results in augmented activity in pri-
However, a stimulus can have a motivationally important sig- mary auditory cortex (Grandjean et al., 2005). Thus, emotion-
nifcance not only for its novelty. An emotional stimulus bears ally relevant stimuli elicit increased neural activity in its corre-
motivational signifcance for the individual as well (for exam - sponding primary cortices the same way as attended stimuli do.
ple a dangerous or pleasant stimuli associated with food or sex). Thus, it is tempting to assume that attention and emotion
Thus, if high arousing emotional stimuli capture attention auto- utilize the same mechanism to achieve enhanced stimulus pro-
matically, they should provoke similar physiologic responses cessing in involved brain regions. If so, emotion and attention
as can be observed during an OR. Bradley, Lang & Cuthbert should have an additive effect with respect of neural activity.
(1993), that pleasant and unpleasant pictures provoke The emotional facilitation of the hemodynamic response in
21STEPHAN MORATTI
FFA is enhanced when participants have to attend to the emo- steady state responses are ideally suited to investigate stimulus
tional face explicitly (Vuilleumier et al., 2001). Activity in pri- related dynamic brain processes over several seconds. It has
mary auditory cortex for attended vs. non-attended meaning- been consistently shown that spatial or feature based attention
less speech that is spoken with an angry prosody is enhanced modulates the ste