The relative role of the left anterior temporal lobe in semantic and language networks has been a matter of active debate in cognitive neuroscience and behavioural neurology. In classic aphasiology, consistent with the distribution of lesions in stroke aphasia, the language network comprises left perisylvian regions (Hillis, 2007; Price, 2012). In such context, lesions of the posterior temporal and inferior parietal regions were associated with word comprehension and retrieval deficits. The description of the severe word and object knowledge deficits in svPPA have challenged this view and supported a cognitive-anatomical model in which the anterior temporal lobe is a fundamental region within the language network, functioning as a semantic hub that links linguistic and perceptual features into a coherent mental representation (Patterson et al., 2007). However, the effect of anterior temporal lobe atrophy on the rest of the language network is still a matter of debate. Recent functional MRI studies provide evidence for altered connectivity related to modality-specific associations between anterior temporal lobe and the rest of the temporal cortex in svPPA, suggesting that anterior temporal lobe atrophy may cause widespread alteration in a distributed semantic network (Goll et al., 2012; Hurley et al., 2015). The current study expands these findings and identifies the left posterior superior temporal and adjacent inferior parietal cortex to be the region with most severely disrupted alpha-beta synchrony in svPPA, likely in relation to its connectivity to the damaged left anterior temporal lobe. Collectively these results indicate that the structural loss of neurons and synapses in the left anterior temporal lobe is strongly associated with the functional disruption of left posteriori perisylvian language cortices. The current results therefore provide a unitary framework between classic neurological models of aphasia and modern cognitive neuroscience approaches by showing that svPPA is characterized by anterior temporal lobe structural damage and left perisylvian functional damage.
A complete discussion of techniques of drafting appropriate and effective claims is beyond the scope of the present work.0.1 The following sections consider selected common problems that arise with claim drafting and Patent and Trademark Office policy toward particular kinds of claim language.
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