, 2008), it appears unlikely that the cognitive changes are simply a consequence or byproduct of other vestibular symptoms (such as ocular motor or postural symptoms). Rather, it is has been suggested that the strong

anatomical links between the vestibular system and hippocampus underpin the behavioural link between the vestibular system and memory (reviewed by Smith et al., 2005b). The central role of the hippocampus in spatial memory has been well documented (Epstein and Kanwisher, 1998 and Maguire et al., 1997). Vestibular input to the hippocampus appears critical for spatial navigation and for updating brain representations of spatial information (Smith et al., 2005b and Stackman et al., 2002). There is considerable neuroanatomical and neurophysiological support for vestibular–hippocampal interactions (see Hufner et al., 2007, Lopez and Blanke, 2011 and Smith, 1997); Epigenetics inhibitor however the anatomical pathways connecting the vestibular system to the hippocampus are less clear and various vestibular–hippocampal pathways have been proposed, which are likely to involve the thalamus (see Lopez and Blanke, 2011 and Smith, 1997). A neuroimaging study in 10

patients who had received bilateral vestibular nerve section 5–10 years before the test and subsequently had a complete acquired chronic bilateral vestibular loss exhibited a significant, selective INCB024360 supplier bilateral atrophy of the hippocampus (16.9% decrease relative to controls), that was correlated

with spatial memory deficits (Brandt et al., 2005). In contrast, patients with unilateral vestibular neurectomy did not demonstrate such hippocampal atrophy (Hufner et al., 2007), suggesting the vestibular input from one intact labyrinth appears to be sufficient to maintain the gross volume of the hippocampus in humans. In sum, evidence derived from animal and human studies suggest that vestibular loss can lead to spatial memory Metalloexopeptidase and spatial navigational impairments which appear to be attributed to the anatomical links between the vestibular system and the hippocampus. Links between anxiety/panic and dizziness/vertigo have been described in medical literature since ancient times (see Balaban and Jacob, 2001 for a historical review). The link appears to be a complex, two-way interaction whereby people with anxiety, depression and other psychiatric symptoms commonly report vestibular symptoms (such as dizziness), conversely, people with vestibular dysfunction can experience a range of psychiatric/affective symptoms, predominantly anxiety, agoraphobia and depression (e.g. Balaban and Jacob, 2001, Balaban and Thayer, 2001, Eckhardt-Henn et al., 2008, Godemann et al., 2004 and Pollak et al., 2003).