Emotional brain and vision Flashcards
0 - Quotes
“Optimistic people see the world through rose colored glasses, both rage and love can blind us”
Adolphs 2004 Nature
“One out every two neurons in each brain is involved in processing of visual information.” O’Shea 2008
0 - Visual creatures
O’Shea 2008
Visual information have a large adaptive role
> detect potential danger
> social signs to regulate human interactions
Perception of faces
intentions, motivation and mood of individuals
Crucial link between vision and emotions
> EMOTIONAL VISION
OUTLINES
I. Emotions …?
- *II. Visual induction of emotions**
a) Which visual stimuli ?
b) Charcteristics of stimuli - *III. Brain coding of emotional vision**
a) Where in the brain?
b) At what time ?
c) What about the neural code (elec/chemic/magnet)?
IV. The peripheral vision : a new way to test emotion
Q1 : Does the impact of emotion still occurs in PV ?
Q2 : Peripheral emotional salience interfere with goal-directed processing of CV ?
Q3 : could the PV interference on CV be modulated by anxiety and depression?
Conclusion
Beyond emotional vision …
I. Emotions
Darwin, Ekman, Panksepp, Sherer, Davidson, Lang, Damasio
Complex neurobiological reality
3 main components :
neurocognitive : appraisal, feelings
physiological : autonomic, hormonal
behavioral : speech, facial, postural
BRAIN PROCESSES & BODY REACTIONS
II. Visual induction of emotions
a) which visual stimuli
Scenes, faces, body, words
Scenes pictures
International Affective Picture System
IAPS
Videoclips
short but intense : high impact (study on sleep)
Emotional faces expression - static
Avec ou sans context
Standardized natural databases (NimStim, Kdef)
Avatars (morphing technics with autist)
Variation de visage de colère vers neutre à colère pour déceler un threshold
Emotional faces expression - dynamic
More efficient - bigger impact - more clear results
Better recogntion - higher activity in face responsive region
Crossmodal visu + audio
Words
> Emotional Stroop : CANCER COLLAPSE More diff when emotional W
> ★Rapid Serial Visual Presentation (RSVP)
Very high speed (100ms/item)
RT: Unpleasant < pleasant < neutral
II. Visual induction of emotions
b) characteristics of stimuli
Crucial step : important of very good selection
Choose a model : Lang’s model of emotion (99)
3 dim : valence, activation, dominance
VALENCE : Unpleasant - pleasant
ACTIVATION : Relaxed - excited
SAM : Self Assesment Manikin (Bradley & Lang 94)
Choose
stronger valence than neutral
Same activation for P and U pix (can’t explore the two effects)
diff male/female
Arousal : quadratic U relation
U≈P>N
★ to be checked before the study !
[EDA - EEG - EEP]
Valence : linear relation
U < N < P (3 kind of emotion)
[HR - corrugator (EMG) : U>N>P - Thermal cam]
(3rd dimension : dominance from Russel)
II. Visual induction of emotions
b) characteristics of stimuli (2/2)
Pictures must be equated for :
gender
content : animal, object, face, ppl
Size (Mo)
Luminance & color saturation
Spatial frequency content
> Diff only for emotional values
3 steps
Researcher choice
“ a priori” values (e.g. : IAPS) values of Valence/Arousal
↓
EXPERIMENTATION
↓
SAM : a posteriori values
★ important to validate the choice of picture for both arousal and valence
La validation se fait par corélation linéaire des valeurs a-priori et a-posteriori pour arousal et valence
III. Brain coding of emotional vision
a) Where in the brain?
Emotional Scenes
PET,FMRI studies (indirect) : occ cx, PF, ACC, Amy
MEG (direct) : ROxC
2 theories
R : UP / L : P
R : better in coding activation
Emotional faces
Amy (asym clear for cortical, not for sub-cortical)
Face responsive IOG, FG, STS
Digust faces : insula lobe
Activation : Fearful face > happy faces
FFA : activation fearful>neutral
Spatial brain coding of emotional vision
[Synthesis of 100 studies by Sabatinelli, 2011]
- *Scenes :** thalamus, occipital cortex.
- *Faces :** face codingareas (FG, IOC, STG)
- *Faces and scenes :** Amy
III. Brain coding of emotional vision
b) At what time ?
EventRelatedPotential (induction ≠ task)
The review 2008 Olofsson (master student)
valence
EPP (100-200 ms) : P1, N170
arousal
LPP ( >300 ms)
————————————————
Hot, Sequeira 2013
Disgust : 140ms
Happiness & Sadness : 160-200ms
————————————————-
Why more RH than LH
RH : UP ++
RH : Activation ++
RH : Faces à droite
Conclusions
Brain temporal coding of emotional vision
Typical windows of activation
> faces (170 ms)
> scenes (200-300 ms)
> words (300-600 ms)
Time courses for coding emo faces
10-30 ms : Thalamus / Amygdala
50-70 ms : V1
100-300 ms : Insula (disgust) - ACC, OF (anger, fear)
III. Brain coding of emotional vision
c) What about the neural code (elec/chemic/magnet)?
Oscillatory responses
alpha (8 à 12 Hz between asleep and awake)
beta (12 à 30 Hz, awake)
theta (4 à 8Hz sommeil léger)
delta (deep sleep)
gamma, mu …
Tous ces rythmes contribuent à l’explication de l’activité électromagnétique du cerveau.
Beta : U >> P > N
- *Thalamus :** 10-30ms Rythme ?
- *V1 :** 50-70ms Beta
- *Prefrontal-Insula** : 100-300ms Beta
IV. The peripheral vision : a new way to test emotion
Most visual events occur in the peripheral vision before to be analysed by the fovea
Stimulus in PV elicits saccades which displace interest into central vision (fovea) for a detailed analysis.
★ Double interest
1/ To test the capacity of emotional salience to be adaptive in low visual conditions….
2/ To find new ways for the neurovisual reeducation of central vision pathologies (Age-relatedMacular Degeneration,AMD).
IV. Protocols to test emotion in PV
Healthy participants
Emotional scenes or emotional faces
Panoramic screen
CV and/or PV eccentricities
Behavioral responses (RT) and ERPs or MEG signals
IV. Q1: Does the impact of emotion still occur in peripheral vision ?
Emotion in PV : faster RT & larger N170 (Rigoulot et al 2011/2012)
Implicit and explicit
Preferential neural coding of emotional expressions (fear, happy) persists in PV.
Abilities of humans to process emotional saliency in impoverished conditions of vision … (subliminal, parietal negect, affective blindsight, …).
IV. Q2: Does the peripheral emotional salience impact goal oriented activity in central vison ?
D’Hondt+ 2013 - Hypothesis
Peripheral emotional salience could interfere with the goal-directed processing of foveal information;
We explored a spatial response bias when the participant judges the orientation of a central arrow. MEG + RT
1/ Emotional information in PV interferes with the CV performance RTE< RTNeutral.
2/ Such interference is correlated with an early (135 ms) increase of neural activity in the left orbito-frontal cortex.
Emotional signals in PV « Guide Us »: grab attentional resources in goal oriented behaviors under the control of CV.
IV. Q3: Could this impact be modulated by personality traits ?
Spatial response bias
State anxiety ++ = congruence effect ++
State-anxiety
modulates the interference of peripheral vision on foveal performance.
Over-functionning of networks which increases responses to emotional stimuli.
Persistence of this over-functionning could favor emergence and maintenance of anxiety disorders.
