Vision and spatial cognition : Neurocognition of perception-action relations Flashcards
Outline
1. Rôle précoce de l’action sur la vision
2. Rôle de l’action dans la perception des objets
- *3. Rôle de l’action dans la perception spatiale**
1. La perception spatiale se construit par l’action
2. La perception spatiale est discontinue
3. Bases neurales de l’espace péripersonnel
4. Codage des objets dans l’espace péripersonnel - Effet de la localisation
- Effet des propriétés fonctionnelles*
5. Rôle du système moteur
6. Validation du modèle
7. Implication pour la pathologie - Déficit spatial localisé
1 - Early role of action on vision
Babies : before starting to interact with env, 2D vision like (dist btw obj = obj closer)
Held & Hein 1963
Kittens
> dark room 12 weeks : no dev of vision system
> Light 3h/d 6 weeks
> similar visual exp, diff visuo-motor exp (active/passive)
Res : passive has same behavior than blind cat
Motor activity coupled to vision is necessary to build a 3D perception of space
++ Mike May recovering sightness after 40 years
(2003, Nature neurosciences)
Deficit in 3D perception even after 2 years
++ Sequences of directions on a 3D dots matrix (Gandhi, Ganesh)
Long sequences : perf of blind real low
Teenagers after surgery (18w after) : perf like C
Coupling motor activity and vision allow to improve perception and representation of space
2 - Dual path model
Model : Goodale & Milner (95,08)
If action is necessary for perception, it must influence it for building 3D space.
Dorsal way 40/80 ms before
(latency of activation in brain visual area : Novak-Bullier 97)
> Sensory binding
2 - Motor action reduces temporal asynchrony
PSS : point of subjective simultanity
Corveleyn et al, 2012
Temporal jugement > which attribute changes first : color/position
Color should be changed 40ms before to be perceived as synchronous
Passive (perceptual) & active (motor pointing) condition
Results
Perceptual
PSS : 38 ms (point of subjective synchrony)
Motor
No more asynchrony
>> Sensory binding with action
2 - Theory of prediction model
Wolpert 90’s
Coello, Delevoye 2007
1) Un stimulus visuel donne lieu à une action et à des conséquences sensorielles
2) Création d’une association entre action et sensation
3) Création d’une association entre vision et action
4) Développement d’une représentation interne des relations entre vision et action (modèle inverse)
5) Développement d’une représentation des relations entre vision et conséquences sensorielles (modèle direct)
6) La representation interne des relations vision-conséquences sensorielles permet la constitution d’un système prédictif anticipant les conséquences des actions (goal of the brain is to predict)
7) L’anticipation de la conséquence des actions influence la perception
2 - Modèle prédictif : representation du but de l’action
We reprensent ONLY the goal of the action
Corveleyn & Coello 2014
meme paradigme
MID : Changement intervient au milieu du mouvement (pic de vitesse)
END : Changement intervient en fin de mouvement
PSS
Passive : 43ms
MID : 40ms
END : 10ms
If it was just action, without goal, no enhancement of perception
2 - Modèle prédictif : contraintes temporelles
How does the sensory binding last ?
If jitter too big, I can’t decide the action was from me (AGENCY)
Changement après le mouvement
250/300ms
au delà, asynchrony
2 - Modèle prédictif : contraintes spatiales
Over 4 cm : loss of the effect
2 - Modèle prédictif : apprentissage
Adaptation procedure :
60% color/pos synchronous
40% test to see the effect
Passive
Before/After : no change 30ms
Motor
Pre : 30ms
Post : 3ms
Sensory binding lasts 250/300ms but can be differed on time
2 - EEG Analysis
P100 occipital cortex
pre adaptation < post adaptation
Anticipating
La réalisation d’une action optimise les traitements sensoriels à l’endroit du but de l’action et au moment où celui ci est atteint (ou à la suite d’un délai en cas d’apprentissage).
3 - Role of action in spatial perception
La perception spatiale est DISCONTINUE
Animals flight zone > fight zone
Humans > Thresholds due to sensory system (old view)
touch < smell < hear < see
> Functional thresholds
Diff spaces for diff actions : brain uses motion parallax (vision) to control posture & locomotion
Espace corporel < pericorporel < peripersonnel < extra personnel accessible < extra personnel distant
3 - Neuroanatomic aspects
Frontal : intention motrice
Voie dorsale : closed action
Voie ventrale : Long distance action (throw somthing)
Voie médiane : motricité symbolique (gesture / apraxia)
3 - Peripersonal space
- Contains the objects that we can immediately reach,
- Specifies our private area in social context
- Contains the obstacles to which the organism must pay attention in order to avoid colliding with them, in particular when gesturing.
3 - Methods to study pps
Reachness test (Coello Delevoye)“Can you reach this object ?”
> logistic function
Aligment test (Constantini)“Green or red ?”
Simon effect because of handler of the cup (closed)
Bissection test (Longo et al)
Deviation to the left for pps and to the right for further away
> RH more involved in closed activity ?
3 - Neural basis of pps
Visual fields
Left & right
only nasal projections on retina cross at chiasma
Up
what’s coming from upper visual field (far) > bottom of retina > bottom of calcarine sulcus > ventral pathway processing (vice versa)
Dorsal stream related to action because deals with what is btw you and the object (same conclusion than Previc)
Boundaries measures
Preliminary measure of reachability and response time
> method of constant stimuli = cylinders, distance 0.2 to 1.6m by step of 5 cm x 4 trials
Reachability boundaries :
90% - 150 % : boundaries
> 150% : extrapersonal
4 - Coding objects in pps : localisation effect
Culham et al 2008 : SPOC activtity increases when :
- object touched, reached and passive viewing of reachable objects
→ automatically coding near objects
4 - Coding objects in pps : functional properties effect
Kalenine et al (2015)
Virtual reality - RT
Task
Can you reach the object ? [manipulation prop]
Is it present in the kitchen ? [functional prop]
→ response with foot to avoid interference with mvt involved in the object
Stim
non conflictual obj (nco) : manipulate = function
conflictual obj (co) : manipulate ≠ function
Diff distance in % of pps (boundaries measured)
Hyp
[manip] influenced by distance
[func] Quicker for non conflictual obj
Res
Semantic task : no effect of space - faster in pps for nco
Reachability : faster in pps for nco
Interpretation
Les aspects fonctionnels et de manipulation sont activés lors de la présence d’un objet dans l’espace péripersonnel.
Les aspects fonctionnels et de manipulation font partis des connaissances sémantiques sur les objets.
5 - role of motor system
4K stereoscopic projection
Virtual reality : possible to build reachable objects thatn are not graspable : distorted object with pixelised contours
N = 12
Object: normalised 7.5 cm width (variable height), same colour 20 objects (bottle, glass, can, gourd, hourglass, dice, ball, vase …) **\>\>** Prototypical & distorted
Tasks
Preliminary task : Boundary of pps
Reachability jugement task
Object identification
[SEE EEG & MOTOR ACTIVATION]
Results
Reachability task : lower RT for pps & eps (slower on boundaries)
Zoom on 8-13Hz : huge decrease of μ-rythm in pps for prototypical objects (no sign change for identification)
Motor sys involved in visual processing of pps
μ-power
decrease not the same w/r space only for prototypical objects
→ Motor sys only gets activated when you want to reach the object
L’implication du système moteur n’est pas automatique mais dépend de la tâche perceptive (distance is not enough) etde la familiarité des objets (experience is important).
5 - EEG and motor activation
Motor system activation : maximal over parieto central area (rolandic and sensorimotor area) little bit controlateral
Just before the action : huge decrease of activity then increase (no increase when only imagining)
Analysis of periodin activity (1Hz > 45 - 80Hz)
μ rythm
Motor sys activated : alpha activity 8-13Hz (sure it’s motor sys)
Time frequency analysis = link btw function & time freq
μ desynchronisation = reduction of amplitude
6 - Motor theory of spatial cognition
Predicition is the construction base of pps (embodied approach of space perception)
We use this representation for diff purposes :
- Conceptualisation of space (“give me this cup”)
- Social interaction
7 - Validation of the model : action modification
If pps linked to action, I can change the pps by changing the possibility to act
We know that, tool use modify kinematics of mvt (as if target was closer) and somatosensory morphology of the arm.
Cardinali et al 2009
After tool use : reachability with hand +7 cm
7 - Validation of the model : consequences modification
Modifying the feedback
Bourgeois & Coello 2012
Adaptation of the visuomotor system to a shifted visual feedback affects the perception of peripersonal space in a predicted way. Shifting the spatial consequences of acting in one direction has the effect of moving the boundary of perceived peripersonal space in the opposite direction.
The perception of peripersonal space relies thus on an action-dependent perceptual system which is affected by the calibration state of the motor system .
Ce sont bien les conséquences sensorielles qui sont représentées
8 - Pathology : localized spatial deficit
Berti - Severe right neglect
Line bissection task
pointing (laser) / reaching
near / far
→ toujours fort décalage vers la droite en reaching mais pas en pointage far (only pps)
Constantini 2014
Same task but before and after observing the experimentator performing the task
→ C : near (= near or far+stick) space left bias / far space right bias (we knew)
→ Patients : Post with stick = neglect in far space
Post without stick = no neglect in far space
Gyrus angulaire : pps
Gyrus supramargianl : eps
8 - Pathology : motor planning deficit
LH : motor adjustement (online control)
RH : Motor planning (final pos accuracy) = perception of PPS + attention
Each hemisphere is specialized for controlling different aspects of the motor task. Patients with unilateral brain damage have confirmed substantial deficits in the ipsilesional arm
Lesions in the LH
deficits in the spatio-temporal features of motor trajectories, suggesting a deficit in the on-line control of voluntary action
Lesions in the RH
deficits in final position accuracy, suggesting a specific deficit in accurately planning the initial parameters of voluntary action, with no impairment in on-line control.
