Parieto-occipital Sulcus

VBM comparison between SLD and FD groups demonstrated more gray matter tissue loss in the FD group in the medial occipitoparietal areas, especially in the precuneus, the lingual gyrus, the cuneus, and the surrounding cortex of the parieto-occipital sulcus bilaterally.  

Brain MRI revealed an ischemic lesion in the right medial occipital lobe and the corpus callosum in case 1 and in the right parieto-occipital sulcus (POS) in case 2.  

It is now becoming possible to construct a mechanistic neural-level model of at least some aspects of spatial memory and imagery, with the hippocampus and medial temporal lobe providing allocentric environmental representations, the parietal lobe egocentric representations, and the retrosplenial cortex and parieto-occipital sulcus allowing both types of representation to interact.  

The dominant sources modulating visual perception were localized around the parieto-occipital sulcus.  

Occipital spikes were classified into two subgroups, located at the calcarine sulcus and parieto-occipital sulcus.  

Source localization of cueing differences indicated activation centered around the parieto-occipital sulcus during reaching of the immediate action goal, followed by enhanced activation in the anterior prefrontal cortex during transport to the final action goal.  

Six months after the ictus, when he had recovered from his directional disorientation, a functional magnetic resonance imaging (fMRI) study of mental navigation demonstrated prominent activation in the retrosplenial area along the right parieto-occipital sulcus and the circumference of the injured area on the left side. The present study, together with previous investigations including clinical case reports, functional neuroimaging, and anatomical and physiological studies on monkeys, suggests that the 'sense of direction' in a large-scale locomotor environment is subserved by the visual area along the parieto-occipital sulcus, and that bilateral deterioration of this function causes directional disorientation..  

Although activation in pVIP showed no preference for any particular spatial range, the dorsal parieto-occipital sulcus (dPOS) demonstrated a near-space preference, with activation highest for near viewing, moderate for arm's length viewing, and lowest for far viewing.  

The analysis revealed stronger alpha power around the parieto-occipital sulcus during retention of face identities (ventral stream) compared with the retention of face orientations (dorsal stream).  

The distributed MRI-constrained MEG source estimates demonstrated decreased alpha (10 Hz) activity in and around the parieto-occipital sulcus and in the calcarine sulcus of the occipital lobe, following from increased GABA(A)-inhibition by lorazepam.  

The primary sources of the memory-dependent alpha activity were in the vicinity of the parieto-occipital sulcus.  

The rCBF contrast weighted by the amplitude of the SSVERs first harmonics showed activation of a swath of cortex perpendicular to V1, including mostly the inferior half of the parieto-occipital sulcus.  

RESULTS: The points studied were the anterior sylvian point, the inferior rolandic point, the intersection of the inferior frontal sulcus with the precentral sulcus, the intersection of the superior frontal sulcus with the precentral sulcus, the superior rolandic point, the intersection of the intraparietal sulcus with the postcentral sulcus, the superior point of the parieto-occipital sulcus, the euryon (the craniometric point that corresponds to the center of the parietal tuberosity), the posterior point of the superior temporal sulcus, and the opisthocranion, which corresponds to the most prominent point of the occipital bossa.  

The retinotopic organization of a newly identified visual area near the midline in the dorsalmost part of the human parieto-occipital sulcus was mapped using high-field functional magnetic resonance imaging, cortical surface-based analysis, and wide-field retinotopic stimulation.  

Contrasting trials with reported ventriloquism-effect versus the no-binding condition revealed activation in the insula, superior temporal sulcus and parieto-occipital sulcus.  

However, even when controlling for the effects of hippocampal volume, higher recall across months was associated with thicker cortex of distinct areas including parts of the gyrus rectus, the middle frontal gyrus, the parieto-occipital sulcus and the lingual gyrus of both hemispheres.  

We bilaterally measured the distance between the superoanterior gyrus and the cranium as the frontal subarachnoid space (FSS) and the distance between the cortex in the parieto-occipital sulcus and the cranium as the parietal subarachnoid space (PSS).  

We found that the emotional expectancy cue specifically produced activation in the supracallosal anterior cingulate, cingulate motor area, and parieto-occipital sulcus.  

In contrast, there was an additional increase in activity in the posterior part of rostral PMd, superior parietal lobule and parieto-occipital sulcus bilaterally as well as in the right anterior intraparietal sulcus, when the visuospatial cue imposed specific constraints on response selection.  

His pattern of dysfunction suggests damage only to the medio-dorsal pathway, an inference that is consistent with structural imaging data, which revealed a lesion encompassing the right parieto-occipital sulcus..  

The anterior wall of the parieto-occipital sulcus (POs) of the macaque monkey, classically considered as part of Brodmann's area 19, contains two functionally distinct areas: a ventral, purely visual area, V6, and a dorsal area, V6A, containing visual neurons and neurons related to the control of arm movements.  

AD patients had predominant lower alpha band sources in the temporal regions, whereas in the controls, robust alpha sources were found near the parieto-occipital sulcus.  

Results show that area V6 occupies the ventral part and fundus of the parieto-occipital sulcus, as well as the ventral part of the precuneate cortex. We therefore suggest that the term V6 is a more appropriate designation of the visuotopically-organized area located on the anterior wall of the parieto-occipital sulcus..  

The temporal crescent syndrome or half-moon syndrome is a rare mono ocular retrochiasmatic visual field defect that can be correlated to a lesion along the contralateral parieto-occipital sulcus.  

For two observers, ICA revealed a second component near the parieto-occipital sulcus.  

Magnetoencephalography of a visual area along the human parieto-occipital sulcus suggested that this region represents the human homologue of the monkey visual area V6 complex (visual area V6/visuomotor area V6A) involved in the integration of visual and somatomotor information. We used functional magnetic resonance imaging at 2.0 T and 2 x 2 x 3 mm3 resolution (16 sections) to characterize visual areas along the parieto-occipital sulcus in five healthy human subjects. Along the parieto-occipital sulcus, and in contrast to primary visual areas, luminance stimulation evoked much larger activation volumes than checkerboard stimulation. Moreover, based on anatomic landmarks, luminance stimulation identified two functionally distinct regions of parieto-occipital sulcus activations: an inferior part (supposedly visual area V6) and a superior portion (supposedly visuomotor area V6A).  

We sought to rectify these problems with a new coordinate system, the Sydney system, in which the fundamental axis runs in the medial sagittal plane from the anterior edge of the corpus callosum to the posterior end of the parieto-occipital sulcus.  

There was one discrete area that was active bilaterally; the posterior intraparietal sulcus close to the parieto-occipital sulcus.  

In order to study the involvement of area V6A in visually guided behavior, restricted lesions to the anterior bank of the parieto-occipital sulcus (POs) were made in two adult Cercopithecus aethiops monkeys, trained in visuomotor tests.  

The cortical area V6A, located in the dorsal part of the anterior bank of the parieto-occipital sulcus, contains retino- and craniocentric visual neurones together with neurones sensitive to gaze direction and/or saccadic eye movements, somatosensory stimulation and arm movements.  

We further show that transient activity occurs in the parieto-occipital sulcus as early as 100-400 ms after flicker onset, which is negatively correlated with the later occipital activity.  

Comparing conditions where a target object that can appear at an unpredictable location with conditions where the target object appears at a predictable location revealed activations in the left superior parietal lobule, the left parieto-occipital sulcus and the right intraparietal sulcus.  

In order to assess the role played by area V6A in visuomotor control, two adult green monkeys ( Cercopithecus aethiops) were subjected to small, bilateral lesions in the anterior bank of the parieto-occipital sulcus.  

It was also determined the mean distance between the parieto-occipital sulcus and the lambdoid suture. In the imaging studies, especially magnetic resonance, it was possible to identify the preoccipital notch and/or a protuberance in the cranial vault related to this notch, besides the parieto-occipital sulcus and lambdoid suture, making possible, therefore, the definition of the anterolateral limit of the occipital lobe..  

The anterior bank of the parieto-occipital sulcus (APO) was strongly activated in all 16 subjects examined.  

Directing the right-hand index finger toward one target dot in an array of five was related to activations distributed over dorsal extrastriate visual cortex (putative area V3A), along the parieto-occipital sulcus (putative V6/V6A) and the posterior intraparietal sulcus (IPS).  

A network of areas was identified consisting of a temporoparietal pathway running between the precuneus and parahippocampi via retrosplenial cortex and the parieto-occipital sulcus, left hippocampus, bilateral posterior parietal, dorsolateral, ventrolateral and anterior prefrontal cortices, and the anterior cingulate.  

Statistical parametric mapping (SPM) revealed a decreased occipital FDG uptake in the patient, particularly at the posterior bank of the parieto-occipital sulcus (putative visual area PO/V6), in the region ventrally bordering V5, and anterolaterally in the calcarine sulcus.  

In the group analysis from 11 subjects, the area with contralateral eye dominance was found in the most anterior part of primary visual cortex where the calcarine fissure merged with the parieto-occipital sulcus.  

It occupies a 'C'-shaped belt of cortex whose upper branch is in the depth of the parieto-occipital sulcus (POS) and lower one is in the depth of the medial parieto-occipital sulcus (POM), with the medial surface of the brain as a zone of junction between the two branches.  

The ipsilateral association connections of the cortex of the dorsal part of the rostral bank of the parieto-occipital sulcus and of the adjoining posterior part of the superior parietal lobule were studied by using different retrograde fluorescent tracers.  

The equivalent sources of the parietal signals clustered within 1 cm3 in the medial parieto-occipital sulcus and did not differ significantly between the stimuli. The strength of the parietal activation remained practically constant with increasing stimulus eccentricity, suggesting that the visual areas in the parieto-occipital sulcus lack the enhanced foveal representation typical of most other visual areas. This result strengthens our previous suggestion that the medial parieto-occipital sulcus is the human homologue of the monkey V6 complex, characterized by, for example, lack of retinotopy and the absence of relative foveal magnification..  

Dynamic representation of eye position in the parieto-occipital sulcus. Area V6A, on the anterior bank of the parieto-occipital sulcus of the monkey brain, contains neurons sensitive both to visual stimulation and to the position and movement of the eyes.  

The calcarine fissure, the parieto-occipital sulcus and the surrounding occipital and parieto-occipital areas were identified as cortical sites of the brain where the alpha rhythm may originate. For four subjects, the majority of the sources were located near or in the calcarine fissure, while for five subjects, they were located near or in the parieto-occipital sulcus and for the remaining subject they were equally divided between the two generation sites..  

It extends from the medial surface of the brain, through the anterior bank of the parieto-occipital sulcus, up to the most lateral part of the fundus of the same sulcus.  

Additionally, activation was found in the cunei in the posterior bank of the parieto-occipital sulcus.  

This report addresses the connectivity of the cortex occupying middle to dorsal levels of the anterior bank of the parieto-occipital sulcus in the macaque monkey.  

Although displaying no difference in average rCBF across tasks, the right MTL showed domain-specific qualitative differences in interactions with posterior dorsal (parieto-occipital sulcus, supramarginal gyrus) and ventral regions (fusiform gyrus, superior temporal sulcus) but not with a prefrontal region.  

Responses to hemifield luminance stimuli also had an occipital component, but they were dominated by activation of the medial parieto-occipital sulcus (POS) 60-70 ms later.  

Subtraction of the static random dot pattern condition from the single-axis motion reversal condition, both contrast-modulated, revealed three significant activations: the anterior parieto-occipital sulcus, the lateral sulcus and the anterior claustrum.  

RESULT: A dilated parieto-occipital sulcus could be seen on computed tomography, and magnetic resonance imaging showed changes consistent with atrophy and gliosis in the cuneus, precuneus, and anterior calcarine cortex surrounding the parieto-occipital sulcus. The temporal crescent syndrome is a rare monocular retrochiasmatic visual field defect that can be correlated to a lesion along the parieto-occipital sulcus..  

The reactive alpha rhythm was generated in the parieto-occipital sulcus, which in several primate species includes areas belonging to the dorsal visual pathway.  

Sources of the posterior 10-Hz (alpha) rhythm clustered mainly around the parieto-occipital sulcus and, to a lesser extent, around the calcarine sulci, with several generators.  

The gestational ages at which the structures were first imaged were: the callosal sulcus, from 14 weeks; the lateral sulcus, from 18 weeks; the parieto-occipital sulcus and calcarine fissure, from 18 weeks; and the cingulate gyrus, from 26 weeks.  

The parieto-occipital sulcus, the anterior and posterior rami of the calcarine sulcus, the cingulate and marginal sulci, and the supracallosal sulcus were delineated manually on sagittally resampled sections.  

Connected systems of parametric meshes were used to model the internal course of the following structures in both hemispheres: the parieto-occipital sulcus, the anterior and posterior rami of the calcarine sulcus, the cingulate and marginal sulci, and the supracallosal sulcus.  

The occupy almost the entire extent of the anterior bank of the parieto-occipital sulcus, V6A being the more dorsal.  

The strongest suppression of the activity occurred near the parieto-occipital sulcus..  

The results showed that when subjects perceived motion, a change in rCBF occurs in areas V5, V1/2, V3 and the parieto-occipital sulcus but not V4, even though the moving stimulus was defined by hue.  

Extracellular recordings were made in the anterior bank of the parieto-occipital sulcus of two waking monkeys trained to perform fixation tasks in normal illumination or in complete darkness. Whether they had a resolvable receptive field or not, the discharge rate of many neurons in the anterior bank of the parieto-occipital sulcus was influenced by oculomotor activity. Neurosci., 9, 1112-1125)-and its output to the visuomotor centres involved in the generation of saccades (frontal eye fields and superior colliculus), we infer that the cortex of the anterior bank of the parieto-occipital sulcus might be part of the network involved in the control of gaze in order to locate objects in visual space..  

An additional right frontal infarct and a cortical microinfarct in a deep left lateral parieto-occipital sulcus were both old lesions and had passed unnoticed clinically.  

The sylvian fissure (21 w.g.a.), the callosal sulcus (21 w.g.a.), the parieto-occipital sulcus (25 w.g.a.), the calcarine fissure (25 w.g.a.), the cingulate sulcus (26 w.g.a.) and the collateral sulcus (25-27 w.g.a.) are visualized rather late with in-utero U.S.  

We have examined the origin and topography of cortical projections to area PO, an extrastriate visual area located in the parieto-occipital sulcus of the macaque.  

In the prestriate-STs projections originating from areas around the parieto-occipital sulcus, a topographic correlation is present; area 19 located anterior to the sulcus projects to the dorsal wall, whereas area 18 situated posterior to the sulcus projects to the ventral wall.  

After injection into the striate cortex of the interhemispheric surface, or into the depth of the calcarine fissure, a second projection was found in the prestriate belt situated in the cortex near the parieto-occipital sulcus.  

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