Understanding how the structure of cognition arises from topographical organization cortex is a primary goal in neuroscience. Previous work has described local functional gradients extending perceptual and motor regions to cortical areas representing more abstract functions, but an overarching framework for association between function still lacking. Here, we show that principal gradient revealed by decomposition connectivity data humans macaque monkey anchored by, at one end, serving...

Abstract The projections to the frontal cortex from various subdivisions of posterior parietal region in rhesus monkey were studied by means autoradiographic technique. rostral superior lobule (area PE) projects dorsal areas 4 and 6 on lateral surface lobe as well supplementary motor area (MII) its medial surface. caudal PE sends connections MII. media (areas PEc PGm) are similar those but they tend concentrate more part 6, MII, cingulate gyrus 24). most also 8. anteriormost inferior PF)...

Abstract The cytoarchitecture of the human and macaque monkey dorsolateral prefrontal cortex has been examined in a strictly comparative manner order to resolve major discrepancies between available segmentations this cortical region brain. In addition, connections areas were re‐examined monkey. present analysis showed that only restricted portion what had previously labelled as area 46 same characteristics brain; remaining part middle frontal gyrus brain included 9. We have 9/46 both...

Evidence from macaque monkey tracing studies suggests connectivity-based subdivisions within the precuneus, offering predictions for similar in human. Here we present functional connectivity analyses of this region using resting-state MRI data collected both humans and monkeys. Three distinct patterns were demonstrated precuneus species, with each subdivision suggesting a discrete role: ( i ) anterior functionally connected superior parietal cortex, paracentral lobule, motor sensorimotor...

The Wisconsin Card Sorting Task (WCST) has been used to assess dysfunction of the prefrontal cortex and basal ganglia. Previous brain imaging studies have focused on identifying activity related set-shifting requirement WCST. present study event-related functional magnetic resonance (fMRI) pattern activation during four distinct stages in performance this task. Eleven subjects were scanned while performing WCST a control task involving matching two identical cards. results demonstrated...

Regional cerebral blood flow was measured with positron emission tomography during the performance of verbal working memory tasks. The same type response (i.e., reciting numbers) required in control and two experimental In task, subjects were to count aloud. tasks, maintain within numbers they generated (self-ordered task) or by experimenter (externally ordered task). Examination difference activation between these conditions revealed strong bilateral mid-dorsolateral frontal cortex both...

A rhesus monkey was trained to move its arm in a direction that perpendicular and counterclockwise from the of target light changed position trial trial. Solution this problem hypothesized involve creation mental rotation an imagined movement vector movement. This hypothesis tested directly by recording activity cells motor cortex during performance task computing neuronal population successive time intervals reaction time. The rotated gradually at average rate 732° per second. These results...

Abstract A comparison of the cytoarchitecture human and macaque monkey ventrolateral prefrontal cortex demonstrated a region in that exhibits architectonic characteristic area 45 brain. This occupies dorsal part convexity just below 9/46v. Rostroventral to brain lies large cortical labelled as 47 by Brodmann. The component this extending far lateral orbital sulcus has characteristics similar those Walker 12 monkey. We designated both 47/12. Thus, 47/12 designates specific zone previously...

1. Two experiments were aimed at investigating the functional organization of human anterior cingulate cortex (ACC) in relation to higher-order motor control. 2. The 15O-labeled H2O bolus method was used measure relative changes regional cerebral blood flow (rCBF) 18 healthy subjects as they performed oculomotor, manual, or speech tasks. 3. Task-specific rCBF obtained distinct subregions ACC, depending on output system employed. oculomotor and manual task-related foci found rostral caudal...

The human brain activity related to strategies for navigating in space and how it changes with practice was investigated functional magnetic resonance imaging. Subjects used two different solve a place-learning task computer-generated virtual environment. One-half of the subjects spatial landmarks navigate early phase training, these showed increased activation right hippocampus. other half nonspatial strategy showed, practice, sustained within caudate nucleus during navigation. Activation...

Previous work in nonhuman primates and patients with frontal lobe damage has suggested that the cortex plays a critical rolein performance of both spatial nonspatial working memory tasks. The present study used positron emission tomography magnetic resonance imaging to demonstrate existence, within human brain, two functionally distinct subdivisions lateral cortex, which may subserve different aspects memory. Five tasks were used, varied terms extent they required executive processes. When...

To explore the extent to which functional systems within human posterior parietal cortex and superior temporal sulcus are involved in perception of action, we measured cerebral metabolic activity subjects by positron emission tomography during simulations biological motion with point-light displays. The experimental design comparisons goal-directed hand whole body motion, object random motion. results demonstrated that scripts action implicates intraparietal caudal part sulcus, both left...

Work with non-human primates had previously demonstrated that the mid-dorsolateral frontal cortex, which comprises cytoarchitectonic areas 46 and 9, plays a critical role in performance of non-spatial self-ordered working memory tasks, whereas immediately adjacent posterior dorsolateral cortex (area 8) is for learning visual conditional associative tasks. The present study used positron emission tomography magnetic resonance imaging to demonstrate existence, within human brain, these two...

Abstract The projections to the frontal cortex that originate from various areas of superior temporal region rhesus monkey were investigated with autoradiographic technique. results demonstrated rostral part gyrus (areas Pro, Ts1, and Ts2) projects proisocortical orbital medial cortex, as well nearby 13, 12, 11, 9, 10, 14. These fibers travel lobe uncinate fascicle. middle Ts3 paAlt) predominantly lateral upper 46, 9) dorsal aspect 9 10). Only a small number these terminated within...

Abstract Vigilance behavior, or watch keeping, involves the focusing of attention on detection subtle changes in environment that occur over a long period time. We investigated time course brain activity during continuous performance 60-min auditory vigilance task. The task required an intensity drop occurred 5% stimuli. Six 1-min samples cerebral blood flow (CBF) and electroencephalographic (EEG) were obtained at l0-min intervals performance. Changes CBF measured by means positron emission...

Monkeys with lesions of the mid-dorsal part lateral frontal cortex, which extends above sulcus principalis as far midline (MDL lesions), were shown to exhibit severe and long-lasting impairments on certain nonspatial working memory tasks: self- ordered externally tasks (experiments 1, 2, 3, 5, 6, 8). These tasks, modeled similar ones previously used patients, measure capacity monitor, within memory, self-generated choices occurrence stimuli. adjacent posterior dorsolateral surrounds arcuate...

Abstract Previous work with both neurosurgical and neurodegenerative patient groups has suggested that high level planning is mediated by neural circuitry which includes the prefrontal cortex striatum. In this study, functional anatomy of cognitive was investigated further, using positron emission tomography (PET). Regional cerebral blood flow (rCBF) measured in 12 normal volunteers while performing easy difficult versions (i) a modified Tower London task; (ii) mnemonic variant task required...