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Topographical Disorientation
Published in Alexander R. Toftness, Incredible Consequences of Brain Injury, 2023
Those first two types were problems with spatial processing: where am I? This next one is a recognition problem: what am I looking at? Damage to the lingual gyrus can lead to landmark agnosia, which is the inability to recognize places. It is also sometimes called topographagnosia or topographic agnosia, and it is similar to other agnosias (see Visual Object Agnosia). Of the four, this is the type of topographical disorientation that appears to be most common and has been studied the most (Aguirre, 2003).
Self-regulation skills training for adults, including relaxation
Published in Harald Breivik, William I Campbell, Michael K Nicholas, Clinical Pain Management, 2008
Recent research indicates cortical effects of hypnotic analgesia exercises, including reduced early receptor potential (ERP) amplitude in response to somatosensory stimuli47 and increased frontal and parietal blood flow.48 A positron emission tomography (PET) study indicated reduced activation of the anterior cingulate gyrus during hypnotic analgesia when the hypnotic instruction was that the pain would bother subjects less.49 However, different wording during hypnosis involving a suggestion of reduced pain perception resulted in analgesia mediated by reduced activity in somatosensory cortex.50 Thus, hypnotic alteration of nociception seems to involve cortical modulation of pain perception. A recent PET study of hypnotic alteration of color vision provides further evidence of changes in primary association cortex function.51 When highly hypnotizable subjects were instructed to perceive a gray-tone grid as filled with color, there was a significant increase in blood flow in the lingual gyrus, the primary brain site for color processing. Conversely, when a colored image was “drained” of color hypnotically, blood flow in that region decreased. Thus, with hypnosis, “believing is seeing,” and hypnotic changes in sensation are accompanied by changes in brain function that indicate an actual change in perception, not merely an altered response to perception.
Neuro-Ophthalmological Findings in Patients with Posterior Circulation Stroke
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Patients with bilateral (and sometimes unilateral) lesions involving the calcarine cortex or surrounding cortical zones (V2 and parastriate and peristriate cortex) show deficits in discerning motion and in detecting the nature, shape, color, and size of objects, bilaterally or within the hemianopic field (Table 23.1). One way of describing abnormalities that are located either above (upper bank) or below (lower bank) the calcarine cortex refers to aspects of visual and visual-spatial functions. The lower bank is specialized in aspects that tell what an object is and the upper bank relates more to the where aspects and visual-spatial relationships.5,6 In area V4, including the caudal portion of the lingual and fusiform gyri (areas 18,19,37) on the lower bank of the calcarine fissure, neurons are sensitive to color patterns. Areas within the lower bank of the calcarine cortex (fusiform and lingual gyri) are specialized for detecting the nature of objects (their color, size, shape, and name) and their movements. An example of difficulty in recognizing the nature and details of an object is prosopagnosia, defective facial recognition. Prosopagnosia is caused by lesions in the lingual and fusiform gyri, most often in the medial portion of the fusiform gyrus, often bilaterally but occasionally unilaterally. Occasionally prosopagnosia patients have lesions in anterior temporal cortex indicating more a difficulty in remembering faces than in facial recognition. Despite severe defects in object recognition and revisualization, patients with lower bank lesions usually do not get lost, can localize objects in space, and may retain normal visual-spatial abilities. Emboli most often cause inferior calcarine bank or full PCA territory infarcts.1
Influence of the hypothalamus–pituitary–gonadal axis reactivation and pubertal hormones on gray matter volume in early pubertal girls
Published in International Journal of Neuroscience, 2021
Lu Zhou, Tao Chen, Yu Wang, Yuchuan Fu, Xiaoling Xie, Xiaozheng Liu, Wei Chen, Zhihan Yan, Peining Liu
Present study showed that girls in the HPG+ group had significantly higher GMV in the bilateral lingual gyrus compare to the HPG − group. The lingual gyrus is important to vision processing and semantic processing [45], including visual memory [46], vivid visual imagery [47] and identification and recognition of words [48]. Visual memory dysfunction and visuo-limbic disconnection have been shown in cases where the lingual gyrus has been damaged (due to stroke or other traumatic brain injuries). Since selective neuroanatomical properties might mature in conjunction with the secretion of distinct HPG axis hormones [6] and previous studies highlight the important role of the lingual gyrus in visual cognitive development. The GMV changes within the lingual gyrus in our study may be related to the comprehensive effects of HPG axis related hormones. Our data provide further evidence supporting the notion that pubertal hormone-related brain structural changes are crucial for cognitive development during early puberty.
Cortical Alterations by the Abnormal Visual Experience beyond the Critical Period: A Resting-state fMRI Study on Constant Exotropia
Published in Current Eye Research, 2019
Hongmei Shi, Yanming Wang, Xuemei Liu, Lin Xia, Yao Chen, Qinlin Lu, Benedictor Alexander Nguchu, Huijuan Wang, Bensheng Qiu, Xiaoxiao Wang, Lixia Feng
The lingual gyrus, located in Brodmann area 18 (BA18), is the major component of cortical visual area V2 and thus plays a prominent role in visual memory,26 vivid visual imagery,27 and different functions of vision. These functions include color motion,28 identification of facial expressions of emotions,29 and recognition of words.30 Being a primary component of the early visual cortex, V2 appears to be essential for conscious visual awareness.31 Besides, previous studies have already presented that right BA18, BA19, and BA732 are responsible for processing stereopsis. V2 is highly activated in patients with infantile exotropia, providing evidence that it is potentially involved in optical fusion.33 Huang et al.34 observed that patients with concomitant strabismus show increased ReHo values in the V2, which may compensate for the dysfunction of optical fusion. Moreover, Qian et al. found obvious activation in V2 in IXT35 and speculated that more activation was needed to keep the fixation on fusion images during performance in visual tasks. In the present study, we also found higher ReHo values in patients with XT than in HCs. Here, we speculate that the increased ReHo values in the V2 may reflect a functional compensation for binocular fusion dysfunction in XT, which is consistent with previous research results. Meanwhile, in our study, XT presents with severe stereopsis impairment; thus, we believe this is probably associated with the abnormalities of the right V2.
Objective and biological markers in bipolar spectrum presentations
Published in Expert Review of Neurotherapeutics, 2019
Trisha Chakrabarty, Lakshmi N. Yatham
Two studies associated cyclothymic temperament scores in non-clinical samples with decreased lingual gyrus activation during a task involving esthetic judgment of paintings, and increased activation during a working memory task [86,87]. Lingual gyrus activity was previously found to be increased while completing a cognitive task in unaffected BD relatives and decreased in meta-analyses of BD patients completing cognitive tasks [71,88]. Cyclothymic temperament was also associated with greater glucose metabolism in the right superior parietal lobule in the resting state, and hyperthymic temperament with changes in left inferior orbitofrontal cortex activation (both increased and decreased activation reported in two studies) in response to a brightness judgment task [69,89,90].