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Annual Review of Vision Science Sep 2019Humans are remarkably adept at perceiving and understanding complex real-world scenes. Uncovering the neural basis of this ability is an important goal of vision... (Review)
Review
Humans are remarkably adept at perceiving and understanding complex real-world scenes. Uncovering the neural basis of this ability is an important goal of vision science. Neuroimaging studies have identified three cortical regions that respond selectively to scenes: parahippocampal place area, retrosplenial complex/medial place area, and occipital place area. Here, we review what is known about the visual and functional properties of these brain areas. Scene-selective regions exhibit retinotopic properties and sensitivity to low-level visual features that are characteristic of scenes. They also mediate higher-level representations of layout, objects, and surface properties that allow individual scenes to be recognized and their spatial structure ascertained. Challenges for the future include developing computational models of information processing in scene regions, investigating how these regions support scene perception under ecologically realistic conditions, and understanding how they operate in the context of larger brain networks.
Topics: Animals; Brain; Brain Mapping; Humans; Magnetic Resonance Imaging; Occipital Lobe; Parahippocampal Gyrus; Spatial Navigation; Visual Cortex; Visual Perception
PubMed: 31226012
DOI: 10.1146/annurev-vision-091718-014809 -
Neurosciences (Riyadh, Saudi Arabia) Jul 2015The relationship of the occipital lobe of the brain with schizophrenia is not commonly studied; however, this topic is considered an essential subject matter among... (Review)
Review
The relationship of the occipital lobe of the brain with schizophrenia is not commonly studied; however, this topic is considered an essential subject matter among clinicians and scientists. We conducted this systematic review to elaborate the relationship in depth. We found that most schizophrenic patients show normal occipital anatomy and physiology, a minority showed dwindled values, and some demonstrated augmented function and structure. The findings are laborious to incorporate within single disease models that present the involvement of the occipital lobe in schizophrenia. Schizophrenia progresses clinically in the mid-twenties and thirties and its prognosis is inadequate. Changes in the volume, the gray matter, and the white matter in the occipital lobe are quite evident; however, the mechanism behind this involvement is not yet fully understood. Therefore, we recommend further research to explore the occipital lobe functions and volumes across the different stages of schizophrenia.
Topics: Humans; Magnetic Resonance Imaging; Occipital Lobe; Schizophrenia
PubMed: 26166588
DOI: 10.17712/nsj.2015.3.20140757 -
The Australian and New Zealand Journal... Jan 2017To investigate the prevalence of occipital bending (an occipital lobe crossing or twisting across the midline) in subjects with schizophrenia and matched healthy...
OBJECTIVE
To investigate the prevalence of occipital bending (an occipital lobe crossing or twisting across the midline) in subjects with schizophrenia and matched healthy controls.
METHOD
Occipital bending prevalence was investigated in 37 patients with schizophrenia and 44 healthy controls.
RESULTS
Ratings showed that prevalence was nearly three times higher among schizophrenia patients (13/37 [35.1%]) than in control subjects (6/44 [13.6%]). Furthermore, those with schizophrenia had greater normalized gray matter volume but less white matter volume and had larger brain-to-cranial ratio.
CONCLUSION
The results suggest that occipital bending is more prevalent among schizophrenia patients than healthy subjects and that schizophrenia patients have different gray matter-white matter proportions. Although the cause and clinical ramifications of occipital bending are unclear, the results infer that occipital bending may be a marker of psychiatric illness.
Topics: Adult; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Schizophrenia; Young Adult
PubMed: 27066817
DOI: 10.1177/0004867416642023 -
Visual Neuroscience Jan 2015The ventral surface of the human occipital lobe contains multiple retinotopic maps. The most posterior of these maps is considered a potential homolog of macaque V4, and... (Review)
Review
The ventral surface of the human occipital lobe contains multiple retinotopic maps. The most posterior of these maps is considered a potential homolog of macaque V4, and referred to as human V4 ("hV4"). The location of the hV4 map, its retinotopic organization, its role in visual encoding, and the cortical areas it borders have been the subject of considerable investigation and debate over the last 25 years. We review the history of this map and adjacent maps in ventral occipital cortex, and consider the different hypotheses for how these ventral occipital maps are organized. Advances in neuroimaging, computational modeling, and characterization of the nearby anatomical landmarks and functional brain areas have improved our understanding of where human V4 is and what kind of visual representations it contains.
Topics: Animals; Brain Mapping; Humans; Occipital Lobe; Retina; Visual Pathways
PubMed: 26241699
DOI: 10.1017/S0952523815000176 -
Trends in Cognitive Sciences Nov 2022For centuries, anecdotal evidence such as the perfect pitch of the blind piano tuner or blind musician has supported the notion that individuals who have lost their... (Review)
Review
For centuries, anecdotal evidence such as the perfect pitch of the blind piano tuner or blind musician has supported the notion that individuals who have lost their sight early in life have superior hearing abilities compared with sighted people. Recently, auditory psychophysical and functional imaging studies have identified that specific auditory enhancements in the early blind can be linked to activation in extrastriate visual cortex, suggesting crossmodal plasticity. Furthermore, the nature of the sensory reorganization in occipital cortex supports the concept of a task-based functional cartography for the cerebral cortex rather than a sensory-based organization. In total, studies of early-blind individuals provide valuable insights into mechanisms of cortical plasticity and principles of cerebral organization.
Topics: Auditory Perception; Blindness; Hearing; Humans; Magnetic Resonance Imaging; Occipital Lobe; Visual Cortex
PubMed: 36207258
DOI: 10.1016/j.tics.2022.08.016 -
Nature Communications Nov 2022The cerebral cortex is spontaneously active during sleep, yet it is unclear how this global cortical activity is spatiotemporally organized, and whether such activity...
The cerebral cortex is spontaneously active during sleep, yet it is unclear how this global cortical activity is spatiotemporally organized, and whether such activity not only reflects sleep states but also contributes to sleep state switching. Here we report that cortex-wide calcium imaging in mice revealed distinct sleep stage-dependent spatiotemporal patterns of global cortical activity, and modulation of such patterns could regulate sleep state switching. In particular, elevated activation in the occipital cortical regions (including the retrosplenial cortex and visual areas) became dominant during rapid-eye-movement (REM) sleep. Furthermore, such pontogeniculooccipital (PGO) wave-like activity was associated with transitions to REM sleep, and optogenetic inhibition of occipital activity strongly promoted deep sleep by suppressing the NREM-to-REM transition. Thus, whereas subcortical networks are critical for initiating and maintaining sleep and wakefulness states, distinct global cortical activity also plays an active role in controlling sleep states.
Topics: Mice; Animals; Sleep, REM; Occipital Lobe; Cerebral Cortex; Wakefulness; Sleep; Electroencephalography
PubMed: 36371399
DOI: 10.1038/s41467-022-34720-9 -
Investigative Ophthalmology & Visual... May 2022The purpose of this study was to investigate the cortical electrical activity and electroencephalography (EEG) features of the frontal lobe evoked by dynamic random dot...
PURPOSE
The purpose of this study was to investigate the cortical electrical activity and electroencephalography (EEG) features of the frontal lobe evoked by dynamic random dot stereogram (DRDS) and to probe the functional connectivity (FC) between the frontal lobe and occipital lobe when processing 3D perception based on the binocular disparity.
METHODS
The EEG experiment involved 14 healthy adults with normal stereopsis (<60″) and normal corrected visual acuity (20/20). The Neuroscan system and 32-channel EEG cap were used to record EEG signals based on the DRDS stimuli. The maximum energies of 3 frequency bands (theta-/alpha- /beta-wave) from 13 interesting channels (FP1, FP2, F7, F3, FZ, F4, F8, FC3, FCZ, FC4, O1, OZ, and O2) located in the frontal and occipital lobes were calculated and analyzed. The FC between any two electrodes from the frontal and occipital lobes was calculated based on the Phase lag index (PLI).
RESULTS
The maximum powers of theta- and alpha-waves in most channels of the frontal and occipital lobes were significantly increased (P < 0.05) when the depth perception was evoked by DRDS above the threshold, compared with that without stereo vision. The changes in the maximum powers of both theta- and alpha-waves were significantly different among the 13 electrodes (P = 0.0004 and 0.0015, respectively). Tukey's multiple comparisons showed that the changes in the maximum powers of theta-wave were significantly different in F8 vs. O1, F8 vs. OZ, and F4 vs. O1 (P = 0.0186, 0.0444, and 0.0412, respectively). Moreover, the changes in the maximum powers of alpha-waves were significantly different in FP1 vs. O1 (P = 0.0182). The FCs of theta-waves between the frontal channels and the occipital channels were significantly enhanced when processing the depth perception, compared with those without stereopsis. There was no significant change in the FCs of the alpha-waves when having 3D perception except for FC between F8 and O1 and FC between F8 and OZ.
CONCLUSIONS
The cortical electrical activity in the frontal lobe and the functional connectivity between the frontal lobe and the occipital lobe increase when participating in the processing binocular disparity and obtaining 3D perception. Theta-waves in the frontal lobe may be crucial in the stereo vision.
Topics: Adult; Electroencephalography; Frontal Lobe; Humans; Occipital Lobe; Vision, Ocular
PubMed: 35522304
DOI: 10.1167/iovs.63.5.7 -
Journal of Alzheimer's Disease : JAD 2021D. Frank Benson and colleagues first described the clinical and neuropathological features of posterior cortical atrophy (PCA) from patients in the UCLA Neurobehavior... (Review)
Review
BACKGROUND
D. Frank Benson and colleagues first described the clinical and neuropathological features of posterior cortical atrophy (PCA) from patients in the UCLA Neurobehavior Program.
OBJECTIVE
We reviewed the Program's subsequent clinical experience with PCA, and its potential for clarifying this relatively rare syndrome in comparison to the accumulated literature on PCA.
METHODS
Using the original criteria derived from this clinic, 65 patients with neuroimaging-supported PCA were diagnosed between 1995 and 2020.
RESULTS
On presentation, most had visual localization complaints and related visuospatial symptoms, but nearly half had memory complaints followed by symptoms of depression. Neurobehavioral testing showed predominant difficulty with visuospatial constructions, Gerstmann's syndrome, and Balint's syndrome, but also impaired memory and naming. On retrospective application of the current Consensus Criteria for PCA, 59 (91%) met PCA criteria with a modification allowing for "significantly greater visuospatial over memory and naming deficits." There were 37 deaths (56.9%) with the median overall survival of 10.3 years (95% CI: 9.6-13.6 years), consistent with a slow neurodegenerative disorder in most patients.
CONCLUSION
Together, these findings recommend modifying the PCA criteria for "relatively spared" memory, language, and behavior to include secondary memory and naming difficulty and depression, with increased emphasis on the presence of Gerstmann's and Balint's syndromes.
Topics: Agnosia; Alzheimer Disease; Atrophy; Biomarkers; Diagnosis, Differential; Female; Gerstmann Syndrome; Humans; Male; Middle Aged; Neuroimaging; Neuropsychological Tests; Occipital Lobe; Parietal Lobe
PubMed: 34057092
DOI: 10.3233/JAD-210368 -
Acta Neurologica Taiwanica Dec 2022A 56-year-old, right-handed man with no known past medical history presented with sudden onset of inability to recognize familiar individuals in person, including his...
A 56-year-old, right-handed man with no known past medical history presented with sudden onset of inability to recognize familiar individuals in person, including his wife and his mother. He also couldn't recognize himself in the mirror. There was no weakness, numbness, visual disturbances, or speech difficulty. Face recognition test, using Warrington Recognition Memory Test (1), showed the presence of complete prosopagnosia. The rest of the neurological and cranial nerves examinations were normal. Magnetic resonance imaging (MRI) of the brain showed restricted diffusion at the right temporal and occipital lobes (the fusiform gyrus) [Figure 1]. Magnetic resonance angiogram (MRA) of the brain was unremarkable. The 24-hours Holter monitoring showed paroxysmal atrial fibrillation. The transthoracic echocardiogram and carotid doppler ultrasound scan were normal. He was then treated with rivaroxaban 20mg daily for secondary stroke prevention in non-valvular atrial fibrillation. Face recognition skill training was started in the ward, which includes compensatory strategies to achieve person recognition by circumventing the face processing impairment, and remediation to enhance mnemonic function for face recognition. His prosopagnosia resolved completely after one week. Prosopagnosia, also known as face blindness, is an impairment in recognizing faces. The core defects are the loss of familiarity with previously known faces and the inability to recognize new faces. Patients with prosopagnosia may present with poor recognition of familiar individuals in person or in the photograph, confusion with plotlines in movies or plays with numerous characters, and difficulty distinguishing individuals wearing a uniform or similar clothing. Stroke is the most common cause of acquired prosopagnosia (2). Other less common aetiologies include traumatic brain injury, carbon monoxide poisoning, temporal lobectomy, and encephalitis. Literature has shown that areas involved in acquired prosopagnosia are the right fusiform gyrus or anterior temporal cortex, or both (3). The fusiform gyrus is part of the lateral temporal lobe and occipital lobe in 'Brodmann area 37' (4). The fusiform gyrus is considered a key structure for functionally specialized computations of high-level vision such as face perception, object recognition, and reading. Individuals with fusiform lesions are more likely to have apperceptive prosopagnosia, while those with anterior temporal lesions have an amnestic variant (5). In summary, prosopagnosia can be the sole presentation for the right fusiform gyrus stroke. It is important to recognize prosopagnosia for early stroke diagnosis and avoid misdiagnosing it as a psychiatric or ocular disorder. Keywords: prosopagnosia, fusiform gyrus, stroke.
Topics: Humans; Infarction; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Prosopagnosia; Stroke; Temporal Lobe
PubMed: 35470413
DOI: No ID Found -
PloS One 2018Lack of insight is a core feature of non-affective psychosis and has been associated with poorer outcomes. Brain abnormalities underlying lack of insight have been...
Lack of insight is a core feature of non-affective psychosis and has been associated with poorer outcomes. Brain abnormalities underlying lack of insight have been suggested, mostly in the frontal lobe, although previous research showed mixed results. We used a voxel-based morphometry (VBM) analysis in 108 first-episode non-affective psychosis patients to investigate the pattern of brain structural abnormalities related to lack of insight. In addition, 77 healthy volunteers were compared with the patients classified as having poor and good insight. The shortened version of the Scale to Assess Unawareness of Mental Disorder was used to evaluate insight. Patients with poor insight (n = 68) compared with patients with good insight (n = 40) showed a single significant cluster (kc = 5834; PcFWE = 0.001) of reduced grey matter volume (GMV) in the right occipital lobe extending to its lateral and medial surfaces, the cuneus, and the middle temporal gyrus. In addition, GMV at this cluster showed a negative correlation with the score of the SUMD (r = -0.305; p = 0.001). When comparing patients with poor insight with healthy subjects overall reductions of GMV were found, mainly in frontal and occipital lobes. Hence, poor insight in non-affective psychosis seems to be associated with specific brain abnormalities in the right occipital and temporal cortical regions. Dysfunction in any combination of these areas may contribute to lack of insight in non-affective psychosis. Specifically, the 'right' hemisphere dysfunction underlying impaired insight in our sample is consistent with previously reported similarities between lack of insight in psychosis and anosognosia in neurological disorders.
Topics: Adult; Central Nervous System; Cerebral Cortex; Female; Frontal Lobe; Gray Matter; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Middle Aged; Occipital Lobe; Organ Size; Psychotic Disorders; Schizophrenia; Temporal Lobe
PubMed: 29856773
DOI: 10.1371/journal.pone.0197715