Projections of the temporo-parietal cortex on vestibular complex in the macaque monkey (Macaca fascicularis)

Snyder, Lawrence H., Aaron P. Batista, and Richard A. Andersen. Change in motor plan, without a change in the spatial locus of attention, modulates activity in posterior parietal cortex. J. Neurophysiol. 79: 2814–2819, 1998. The lateral intraparietal area (LIP) of macaque monkey, and a parietal reach region (PRR) medial and posterior to LIP, code the intention to make visually guided eye and arm movements, respectively. We studied the effect of changing the motor plan, without changing the locus of attention, on single neurons in these two areas. A central target was fixated while one or two sequential flashes occurred in the periphery. The first appeared either within the response field of the neuron being recorded or else on the opposite side of the fixation point. Animals planned a saccade (red flash) or reach (green flash) to the flash location. In some trials, a second flash 750 ms later could change the motor plan but never shifted attention: second flashes always occurred at the same location as the preceding first flash. Responses in LIP were larger when a saccade was instructed ( n = 20 cells), whereas responses in PRR were larger when a reach was instructed ( n = 17). This motor preference was observed for both first flashes and second flashes. In addition, the response to a second flash depended on whether it affirmed or countermanded the first flash; second flash responses were diminished only in the former case. Control experiments indicated that this differential effect was not due to stimulus novelty. These findings support a role for posterior parietal cortex in coding specific motor intention and are consistent with a possible role in the nonspatial shifting of motor intention.

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Functional organization of human posterior parietal cortex: grasping- and reaching-related activations relative to topographically organized cortex

Journal of Neurophysiology ◽

10.1152/jn.00657.2012 ◽

2013 ◽

Vol 109 (12) ◽

pp. 2897-2908 ◽

Cited By ~ 74

Author(s):

Christina S. Konen ◽

Ryan E. B. Mruczek ◽

Jessica L. Montoya ◽

Sabine Kastner

Keyword(s):

Neural Networks ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Functional Organization ◽

Macaque Monkey ◽

Superior Parietal Lobule ◽

Movement Type ◽

The Neural Networks ◽

Posterior Parietal ◽

The Relationship

The act of reaching to grasp an object requires the coordination between transporting the arm and shaping the hand. Neurophysiological, neuroimaging, neuroanatomic, and neuropsychological studies in macaque monkeys and humans suggest that the neural networks underlying grasping and reaching acts are at least partially separable within the posterior parietal cortex (PPC). To better understand how these neural networks have evolved in primates, we characterized the relationship between grasping- and reaching-related responses and topographically organized areas of the human intraparietal sulcus (IPS) using functional MRI. Grasping-specific activation was localized to the left anterior IPS, partially overlapping with the most anterior topographic regions and extending into the postcentral sulcus. Reaching-specific activation was localized to the left precuneus and superior parietal lobule, partially overlapping with the medial aspects of the more posterior topographic regions. Although the majority of activity within the topographic regions of the IPS was nonspecific with respect to movement type, we found evidence for a functional gradient of specificity for reaching and grasping movements spanning posterior-medial to anterior-lateral PPC. In contrast to the macaque monkey, grasp- and reach-specific activations were largely located outside of the human IPS.

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Neurophysiology of Prehension. III. Representation of Object Features in Posterior Parietal Cortex of the Macaque Monkey

Journal of Neurophysiology ◽

10.1152/jn.00609.2007 ◽

2007 ◽

Vol 98 (6) ◽

pp. 3708-3730 ◽

Cited By ~ 28

Author(s):

Esther P. Gardner ◽

K. Srinivasa Babu ◽

Soumya Ghosh ◽

Adam Sherwood ◽

Jessie Chen

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Macaque Monkey ◽

Firing Rates ◽

Video Recordings ◽

Object Properties ◽

Area 5 ◽

Somatosensory Input ◽

Posterior Parietal ◽

Object Features

Neurons in posterior parietal cortex (PPC) may serve both proprioceptive and exteroceptive functions during prehension, signaling hand actions and object properties. To assess these roles, we used digital video recordings to analyze responses of 83 hand-manipulation neurons in area 5 as monkeys grasped and lifted objects that differed in shape (round and rectangular), size (large and small spheres), and location (identical rectangular blocks placed lateral and medial to the shoulder). The task contained seven stages—approach, contact, grasp, lift, hold, lower, relax—plus a pretrial interval. The four test objects evoked similar spike trains and mean rate profiles that rose significantly above baseline from approach through lift, with peak activity at contact. Although representation by the spike train of specific hand actions was stronger than distinctions between grasped objects, 34% of these neurons showed statistically significant effects of object properties or hand postures on firing rates. Somatosensory input from the hand played an important role as firing rates diverged most prominently on contact as grasp was secured. The small sphere—grasped with the most flexed hand posture—evoked the highest firing rates in 43% of the population. Twenty-one percent distinguished spheres that differed in size and weight, and 14% discriminated spheres from rectangular blocks. Location in the workspace modulated response amplitude as objects placed across the midline evoked higher firing rates than positions lateral to the shoulder. We conclude that area 5 neurons, like those in area AIP, integrate object features, hand actions, and grasp postures during prehension.

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THE IN VIVO METABOLISM OF CORTISOL AND CORTICOSTERONE BY THE MACAQUE MONKEY (Macaca fascicularis)

Acta Endocrinologica ◽

10.1530/acta.0.0780091 ◽

1975 ◽

Vol 78 (1) ◽

pp. 91-109 ◽

Cited By ~ 6

Author(s):

K. D. R. Setchell ◽

C. H. L. Shackleton

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Adult Female ◽

Human Urine ◽

Macaca Fascicularis ◽

Macaque Monkey ◽

The Other ◽

Gas Chromatography Mass Spectrometry ◽

In Vivo Metabolism

ABSTRACT [4-14C] Cortisol was administered intramuscularly to one adult female macaque monkey, MF3 (Macaca fascicularis). To adult female macaque monkey, MF4, [4-14C]corticosterone was administered intramuscularly. Urine samples were collected and the metabolites excreted identified using gas chromatography, radio-gas chromatography and gas chromatography-mass spectrometry. The principal metabolites of cortisol were identified as glucuronide conjugates of 11-oxygenated-17-oxosteroids. The excretion of tetrahydrocortisol and tetrahydrocortisone relative to the other corticosteroid metabolites was low compared with that of man. Two compounds, 3β-cortol and 3β-cortolone not normally present in human urine were identified in the urine from this species. The principal metabolites of corticosterone were glucuronide conjugates of hexahydroCompound A and hexahydrocorticosterone. Two unidentified radioactive compounds were also present.

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Gustatory responses of single neurons in the insula of the macaque monkey

Journal of Neurophysiology ◽

10.1152/jn.1990.63.4.689 ◽

1990 ◽

Vol 63 (4) ◽

pp. 689-700 ◽

Cited By ~ 173

Author(s):

S. Yaxley ◽

E. T. Rolls ◽

Z. J. Sienkiewicz

Keyword(s):

Macaca Fascicularis ◽

Cynomolgus Macaque ◽

Macaque Monkey ◽

Solitary Tract ◽

Single Neurons ◽

Black Currant ◽

Taste System ◽

Basic Taste ◽

Intensity Response ◽

The Mean

1. In recordings made from 2,925 single neurons, a region of primary taste cortex was localized to the rostral and dorsal part of the insula of the cynomolgus macaque monkey, Macaca fascicularis. The area is part of the dysgranular field of the insula and is bordered laterally by the frontal opercular taste cortex. 2. The responses of 65 single neurons with gustatory responses were analyzed in awake macaques with the use of the taste stimuli glucose, NaCl, HCl, quinine HCl (QHCl), water, and black currant juice. 3. Intensity-response functions showed that the lowest concentration in the dynamic part of the range conformed well to human thresholds for the basic taste stimuli. 4. A breadth-of-tuning coefficient was calculated for each neuron. This is a metric that can range from 0.0 for a neuron that responds specifically to only one of the four basic taste stimuli to 1.0 for one that responds equally to all four stimuli. The mean coefficient for 65 cells in the taste insula was 0.56. This tuning is sharper than that of neurons in the nucleus of the solitary tract of the monkey, and similar to that of neurons in the primary frontal opercular taste cortex. 5. A cluster analysis showed that at least six different groups of neurons were present. For each of the taste stimuli, glucose, NaCl, HCl, QHCl, water, and black currant juice, there was one group of neurons that responded much more to that tastant than to the other tastants. Other subgroups of these neurons responded to two or more of these tastants, such as glucose and black currant juice, or NaCl and QHCl. 6. On the basis of this and other evidence, it is concluded that the primary insular taste cortex, in common with the primary frontal opercular taste cortex, represents a stage of information processing in the taste system of the primate at which the tuning of neurons has become sharper than that of neurons in the nucleus of the solitary tract, and is moving toward the fineness achieved in the secondary taste cortex in the caudolateral orbitofrontal taste cortex, where motivation-dependence first becomes manifest in the taste system.

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