Cortical activation pattern during saccadic eye movements in humans: Localization by focal cerebral blood flow increases

1979 ◽  
Vol 5 (1) ◽  
pp. 79-88 ◽  
Author(s):  
Eldad Melamed ◽  
Bo Larsen
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Eye Movements ◽  
Saccadic Eye Movements ◽  
Cortical Activation ◽  
Activation Pattern ◽  
Cortical Activation Pattern

Saccadic eye movements and regional cerebral blood flow in schizophrenic patients

1997 ◽  
Vol 247 (4) ◽  
pp. 219-227 ◽  
Author(s):  
Mié Matsui ◽  
Masayoshi Kurachi ◽  
Satoru Yuasa ◽  
Mitsuo Aso ◽  
Yasuhiro Tonoya ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Eye Movements ◽  
Regional Cerebral Blood Flow ◽  
Saccadic Eye Movements ◽  
Regional Cerebral Blood ◽  
Schizophrenic Patients

The role of cerebral cortex in the generation of voluntary saccades: a positron emission tomographic study

1985 ◽  
Vol 54 (2) ◽  
pp. 348-369 ◽  
Author(s):  
P. T. Fox ◽  
J. M. Fox ◽  
M. E. Raichle ◽  
R. M. Burde
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Eye Movements ◽  
Supplementary Motor Area ◽  
Task Complexity ◽  
Saccadic Eye Movements ◽  
Motor Area ◽  
Frontal Eye Fields ◽  
Motor Tasks ◽  
Positron Emission

The purpose of this study was to define the location and behavior of cerebral structures within the normal human brain that participate in the generation of voluntary saccadic eye movements. Changes in regional cerebral blood flow (rCBF) during task performance were assumed to reflect like changes in regional neuronal activity induced by the task. The locations of all rCBF changes were described in stereotaxic coordinates. Cerebral blood flow (CBF) was measured with positron emission tomography (PET) and bolus intravenous injection of H2(15)O. The use of H2(15)O with PET allowed six, seven-slice measurements of brain blood flow to be made in rapid sequence for each subject, without removing the subject from the tomograph between scans. Nine paid normal volunteers were studied. The paradigm included three saccadic eye-movement (SEM) conditions, one finger-movement condition and two control conditions (initial and final). The three SEM conditions allowed comparisons to be drawn between targeted versus untargeted SEMs, auditorily cued versus visually cued SEMs, and stochastic versus rhythmic SEMs. All tasks were simple and deterministic in that each movement exactly mirrored the preceding movement: finger flexion then extension, saccade-left then saccade-right. Saccadic eye movements were associated with rCBF increases within the frontal eye fields, the supplementary motor area, and the cerebellum. Finger movements were associated with rCBF changes within the sensorimotor hand areas, the supplementary motor area, and the cerebellum. The frontal eye fields were discrete cortical regions consistently active during the generation of voluntary SEMs and uninfluenced by target presence, type of cue, or task complexity, indicating a predominantly motor function. The supplementary motor area (SMA) was consistently active during all motor tasks and was uninfluenced by the degree of task complexity or stochasticity. A role for SMA in establishing "motor set" during both simple and complex motor tasks is suggested. An anterior-posterior somatotopy was found for SMA-eye (anterior) versus SMA-hand (posterior). Lateral occipital visual association cortex activation was present only during targeted saccadic conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Does motor skill influence the cortical activation pattern in musicians? An f-MRI study

NeuroImage ◽  
1996 ◽  
Vol 3 (3) ◽  
pp. S374
Author(s):  
D. Auer ◽  
R. Jones ◽  
R. Rupprecht ◽  
E. Kraft
Keyword(s):  
Motor Skill ◽  
Cortical Activation ◽  
Activation Pattern ◽  
Mri Study ◽  
Cortical Activation Pattern

Preferred chewing side-dependent two-point discrimination and cortical activation pattern of tactile tongue sensation

2009 ◽  
Vol 203 (1) ◽  
pp. 118-126 ◽  
Author(s):  
Akiko Minato ◽  
Takashi Ono ◽  
Jun J. Miyamoto ◽  
Ei-ichi Honda ◽  
Tohru Kurabayashi ◽  
...  
Keyword(s):  
Cortical Activation ◽  
Activation Pattern ◽  
Cortical Activation Pattern

scholarly journals The Roles of Cerebral Blood Flow, Capillary Transit Time Heterogeneity, and Oxygen Tension in Brain Oxygenation and Metabolism

2011 ◽  
Vol 32 (2) ◽  
pp. 264-277 ◽  
Author(s):  
Sune N Jespersen ◽  
Leif Østergaard
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Oxygen Tension ◽  
Transit Time ◽  
Tissue Oxygenation ◽  
Ischemia Reperfusion ◽  
Cortical Activation ◽  
Oxygen Extraction Fraction ◽  
Normal Brain ◽  
Lower Oxygen

Normal brain function depends critically on moment-to-moment regulation of oxygen supply by the bloodstream to meet changing metabolic needs. Neurovascular coupling, a range of mechanisms that converge on arterioles to adjust local cerebral blood flow ( CBF), represents our current framework for understanding this regulation. We modeled the combined effects of CBF and capillary transit time heterogeneity (CTTH) on the maximum oxygen extraction fraction ( OEFmax) and metabolic rate of oxygen that can biophysically be supported, for a given tissue oxygen tension. Red blood cell velocity recordings in rat brain support close hemodynamic—metabolic coupling by means of CBF and CTTH across a range of physiological conditions. The CTTH reduction improves tissue oxygenation by counteracting inherent reductions in OEFmax as CBF increases, and seemingly secures sufficient oxygenation during episodes of hyperemia resulting from cortical activation or hypoxemia. In hypoperfusion and states of blocked CBF, both lower oxygen tension and CTTH may secure tissue oxygenation. Our model predicts that disturbed capillary flows may cause a condition of malignant CTTH, in which states of higher CBF display lower oxygen availability. We propose that conditions with altered capillary morphology, such as amyloid, diabetic or hypertensive microangiopathy, and ischemia—reperfusion, may disturb CTTH and thereby flow-metabolism coupling and cerebral oxygen metabolism.

Cerebral and systemic hemodynamic changes during cognitive and motor activation paradigms

2005 ◽  
Vol 288 (6) ◽  
pp. R1581-R1588 ◽  
Author(s):  
Michelle Moody ◽  
Ronney B. Panerai ◽  
Penelope J. Eames ◽  
John F. Potter
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Activation ◽  
Cortical Activation ◽  
Hemispheric Dominance ◽  
Metabolic Demand ◽  
Hemodynamic Changes ◽  
Word Generation ◽  
The Right

Cognitive and/or sensorimotor stimulations of the brain induce increases in cerebral blood flow that are usually associated with increased metabolic demand. We tested the hypothesis that changes in arterial blood pressure (ABP) and arterial Pco2 also take place during brain activation protocols designed to induce hemispheric lateralization, leading to a pressure-autoregulatory response in addition to the metabolic-driven changes usually assumed by brain stimulation paradigms. Continuous recordings of cerebral blood flow velocity [CBFV; bilateral, middle cerebral artery (MCA)], ABP, ECG, and end-tidal Pco2 (PetCO2) were performed in 15 right-handed healthy subjects (aged 21–43 yr), in the seated position, at rest and during 10 repeated presentations of a word generation and a constructional puzzle paradigm that are known to induce differential cortical activation. Derived variables included heart rate, cerebrovascular resistance, critical closing pressure, resistance area product, and the difference between the right and left MCA recordings (CBFVR-L). No adaptation of the CBFVR-L difference was detected for the repeated presentation of 10 activation tasks, for either paradigm. During activation with the word generation tasks, CBFV changed by (mean ± SD) 9.0 ± 3.7% (right MCA, P = 0.0007) and by 12.3 ± 7.6% (left MCA, P = 0.0007), ABP by 7.7 ± 6.0 mmHg ( P = 0.0007), heart rate by 7.1 ± 5.3 beats/min ( P = 0.0008), and PetCO2 by −2.32 ± 2.23 Torr ( P = 0.002). For the puzzle paradigm, CBFV changed by 13.9 ± 6.6% (right MCA, P = 0.0007) and by 11.5 ± 6.2% (left MCA, P = 0.0007), ABP by 7.1 ± 8.4 mmHg ( P = 0.0054), heart rate by 7.9 ± 4.6 beats/min ( P = 0.0008), and PetCO2 by −2.42 ± 2.59 Torr ( P = 0.001). The word paradigm led to greater left hemispheric dominance than the right hemispheric dominance observed with the puzzle paradigm ( P = 0.004). We concluded that significant changes in ABP and PetCO2 levels occur during brain activation protocols, and these contribute to the evoked change in CBFV. A pressure-autoregulatory response can be observed in addition to the hemodynamic changes induced by increases in metabolic demand. Simultaneous changes in Pco2 and heart rate add to the complexity of the response, indicating the need for more detailed modeling and better understanding of brain activation paradigms.

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