Ann Psychiatr Clin Neurosci | Volume 2, Issue 1 | Review Article | Open Access
Aziz VM*
Department of Psychiatrist, Devon Partnership NHS Trust, UK
Fulltext PDFAlzheimer’s disease a heterogeneous disorder and genetic factors play an important role in its pathogenesis. Deficits in attention and information processing have been recognised as early features of AD. The Pre Pulse Inhibition of the startle reflex (PPI) is a measure of attention; sensorimotor gating and information processing that are deficient in AD.
Method: The performance of twenty subjects with mild AD, twenty first-degree siblings and thirty healthy controls on the PPI paradigm was examined as well as we provided the first report of PPI performance in first-degree siblings and linked this to APOEԑ4.
Results: Reactivity, onset and peak latencies and PPI 120 were impaired in patients with AD. Siblings showed similar reactivity, slow processing and onset latency to AD cases. The PPI showed a significant difference in PPI 120 between cases and controls. Siblings behaved half-way between cases and controls. In the cases group, subjects without APOEԑ4 variant seemed to be more reactive than those with APOEԑ4 variant. The presence of APOEԑ4 variant has significantly affected onset and peak latency at ISI-120ms.
Conclusion: The effect of PPI confirmed that sensorimotor gating is deficient in early AD. First degree siblings of AD cases have shown some failure of inhibition compared to healthy controls. PPI may be used as a part of battery of biomarkers in aiding clinical diagnosis and early detection of subjects at risk of developing AD such as first-degree siblings.
Aziz VM. Deficit in Sensorimotor Gating in Alzheimer’s Disease (AD): Measuring Pre Pulse Inhibition (PPI) as a Measure of Liability to AD. Ann Psychiatr Clin Neurosci. 2019;2(1):1008.