charles pierrot-deseilligny dan milea rené m. müri eun h. kim february 21, 2008 eye movement...

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Charles Pierrot-Deseillign Charles Pierrot-Deseillign Dan Milea Dan Milea René M. Müri René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by Eye Movement Control by the Cerebral Cortex the Cerebral Cortex

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Page 1: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Charles Pierrot-DeseillignyCharles Pierrot-DeseillignyDan MileaDan Milea

René M. MüriRené M. Müri

Eun H. KimFebruary 21, 2008

Eye Movement Control by Eye Movement Control by the Cerebral Cortexthe Cerebral Cortex

Page 2: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Outline• Purpose• Introduction• Frontal Lobe• Parietal Lobe• Cingulate cortex• Summary• Conclusion

Page 3: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Purpose

To better understand the eye movement control by the cerebral cortex using recent techniques such as transcranial magnetic stimulation and functional magnetic resonance imaging.

http://www.cosmosmagazine.com/node/637

Page 4: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Why study eye movement?

“It gives new meaning to the distinction between 'quantitative' and'qualitative' techniques for evaluating brain-behavior

relationships.” William B. Barr, Chief of Neuropsychology, Comprehensive Epilepsy Center,

New York University School of Medicine

Quantify relatively complex neuropsychological processes 1. attention2. spatial memory 3. motivation4. decisional processes

Page 5: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Introduction• Classic Methods

– Lesion– Electrical Stimulation

• Two recent methods to study eye movement– Transcranial magnetic stimulation– Functional magnetic resonance imaging

Page 6: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

New Methods vs. Old Methods

Page 7: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Transcranial Magnetic Stimulation• Temporarily disrupts the functioning of

a specific region of the brain.

– Magnetic field is applied to a subject’s head which crosses the scalp and skull

– Electric current from Magnetic field disrupts the neural activity

– Inactivation lasts <1 sec• Advantage: increased temporal resolution

www.psych.mcgill.ca/.../Techniques.htm

intra.ninds.nih.gov/Lab.asp?Org_ID=104

Page 8: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Functional Magnetic Resonance Imaging• Non-invasive method• MRI scanner exploits the natural magnetic

properties present in our bodies to obtain image of blood flow in the brain.

• Advantage: increased spatial resolution

http://www.hku.hk/cogsci/media/neuro/1-imaging.jpg

flickr.com/photos/macronin47/85007177/

Page 9: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Control of Human Eye Movement in Cerebral Cortex

• Frontal Lobe

• Parietal Lobe

• Cingulate Cortex

http://www.gpc.edu/~bbrown/psyc1501/brain/lobes2.jpg

Page 10: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Frontal Lobe

• Three main areas involved in eye movement control– Frontal Eye Field (FEF) [BA 8]– Supplementary Eye Field (SEF) – Dorsolateral prefrontal cortex (DLPF

C)[BA9 and BA46]

Page 11: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Frontal Eye Field• Controls Pursuit Eye Movements (PEMs)

– Smooth tracking of an object

• Preparation and triggering of Intentional saccades– Visually guided saccades– Predictive saccades– Memory guided saccades– Antisaccades

Page 12: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

FEF and PEMs• Control two type of PEMs

• Ipsilateral PEMs (main control) • contralateral PEMs (superficial)

• Controls optokinetic nystagmus• Involuntary eye movement to foveate a moving t

arget to maintain the perception of self-motion

– In the monkey, FEF neurons controlling PEMs are also involved in vergence. However, no literature shows vergence FEF activation in humans.

Page 13: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

FEF and Saccades• Antisaccades: intentional saccades to a target

located in the opposite direction.• Two different Mechanisms

– 1. Inhibition of an unwanted reflexive misdirected saccade

• PEF triggers towards the target. DLPFC inhibits and the error between the PEF and DLPFC reflect the inhibition function

– 2.Simultaneous triggering of an intentional correct antisaccade, made in the direction opposite to the target by FEF

Page 14: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Supplementary Eye Field (SMA)

• SEF: connected with FEF, the DLPFC, the anterior cigulate cortex and posterior parietal cortex

• Location: Medial surface of the superior frontal gyrus, in the upper part of the paracentral sulcus.

• Function: involved in motor programmes comprising of saccade with a body movement or successive saccades.

Page 15: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Supplementary Eye Field Cont.• TMS and fMRI studies show that p

re-SEF is involved in motor learning

• SEF is involved in the execution of motor sequence.

Page 16: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Dorsolateral Prefrontal Cortex• Involved in

– saccade inhibition– short-term spatial memory

• TMS support that DLPFC is exerted during delay period when spatial memory is involved.

• fMRI show activity up to 24 second.

– decisional processes • lesion studies show that percentage of predictiv

e saccades decreased significantly.

Page 17: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Parietal Lobe• Posterior Parietal Cortex

• Involved in the control of saccades and attention

• Parietal Eye Field– Corresponds to lateral intraparietal area – Involved in control of saccades and attentional proc

esses.– Projects to both FEF and the superior colliculus

• Parieto-FEF projection: visual fixation• Parieto-superior colliculus projection: saccadic involve

ment

Page 18: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Cingulate Cortex• Divided into the anterior cingulate

cortex (ACC) [BA 24] and the posterior cingulate cortex (PCC) [BA 23].

Page 19: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Cingulate Cortex• ACC: involved in intentional saccade control• Cingulate Eye Field: located between BA 23 a

nd 24, prepare all the frontal ocular motor areas involved in intentional saccade control to act in the forthcoming motor behaviour.

• PCC: reflexive saccade control (?)– fMRI study shows that the PCC is active during refl

exive saccades.– Activation during PEM

Page 20: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Summary

Page 21: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Conclusion

• Recent data have summarized some of the cortical pathways and mechanisms involved in saccade control.

• TMS and fMRI are currently used to understand new information and interpret cortical control of eye movements in humans.

Page 22: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Reference• http://www.neuropsychologyarena.com/books/The-Quantified-Process-A

pproach-to-Neuropsychological-Assessment• www.psych.mcgill.ca/.../Techniques.htm• Intra.ninds.nih.gov/Lab.asp?Org_ID=104• http://fourier.eng.hmc.edu/e180/handouts/figures/brainbrodmannareas.gif• www.schoppik.com/data/articles/jneurosci2006.html• http://www.gpc.edu/~bbrown/psyc1501/brain/lobes2.jpg

I

Page 23: Charles Pierrot-Deseilligny Dan Milea René M. Müri Eun H. Kim February 21, 2008 Eye Movement Control by the Cerebral Cortex

Questions?

www.schoppik.com/data/articles/jneurosci2006.html