Atrophy and decreased activation of fronto-parietal attention areas contribute to higher visual dysfunction in posterior cortical atrophy

Posterior cortical atrophy and Alzheimer’s disease: a meta-analytic review of neuropsychological and brain morphometry studies

“…For example, studies of cortical density and thickness that directly compare PCA and tAD have reported significantly more atrophy of the visual association areas (e.g., the right parietal, bilateral posterior parietal regions and the occipital lobe) in PCA. Additionally, tAD patients were found to have greater volume decreases in the hippocampi and the left medial temporal lobe (Feldmann et al 2008;Lehmann et al 2011;Whitwell et al 2007). Consistent with these findings, several functional imaging studies provide evidence for decreased activation in visual attention areas and the occipital lobes, as well as increased hypometabolism in the inferior occipitotemporal cortex in PCA (Feldmann et al 2008;Kas et al 2011).…”

“…Specifically, atrophy of occipital and parietal regions may result in the visuospatial deficits that have been previously described in PCA (Crutch et al 2012). In addition, functional neuroimaging studies have shown a pattern of hypometabolism and functional underactivation Feldmann et al 2008) in posterior areas (the parietal and/or occipital lobes). This could potentially be related to the increased deposition of senile plaques in these areas observed in PCA (Crutch et al 2012).…”

“…Additionally, tAD patients were found to have greater volume decreases in the hippocampi and the left medial temporal lobe (Feldmann et al 2008;Lehmann et al 2011;Whitwell et al 2007). Consistent with these findings, several functional imaging studies provide evidence for decreased activation in visual attention areas and the occipital lobes, as well as increased hypometabolism in the inferior occipitotemporal cortex in PCA (Feldmann et al 2008;Kas et al 2011). Similarly, when compared to tAD patients in structural imaging studies, PCA patients were found to have a greater global amyloid load in occipital and parietal regions as well as reduced white matter (WM) integrity in posterior regions and severe WM occipital atrophy (Crutch et al 2012;Formaglio et al 2011;Migliaccio et al 2012a, b).…”

“…Four neuroimaging (Feldmann et al 2008;Lehmann et al 2011;Migliaccio et al 2009;Whitwell et al 2007) and eight neuropsychological (Aresi and Giovagnoli 2009;Caprile et al 2009;Charles and Hillis 2005;Croisile et al 2010;Kas et al 2011;McMonagle et al 2006;Migliaccio et al 2009;Nestor et al 2003;) studies met inclusion criteria (See Online Fig. 1 for the detailed flow diagram).…”

Posterior Cortical Atrophy: A Case Study of Benson's Syndrome That Initially Presented as Anxiety Disorder

“…Multiple regions of brain activity are correlated with the subjective experience of anxiety including portions of the parietal and ventral temporal lobe (Engels et al, 2007;Heller, Nitchke, & Miller, 1997). The white-matter involvement reported by Duning et al (2009) and the involvement of the ACC and frontal areas reported by Feldmann et al (2008) both provide some evidence that parietal or frontal disconnection, as well as cingulate involvement, may be implicated in the simultaneous presentation of psychiatric symptoms. It is possible that the atrophy within these regions as well as subsequent loss of input to frontal regions serves to create a cascade of events that lead to autonomic changes, worry, and the automatic thinking that are observed with anxiety.…”