No association between prepulse inhibition of the startle reflex and neuropsychological deficit in chronic schizophrenia

Abstract

Sensorimotor gating deficits are relevant in schizophrenia and can be measured using prepulse inhibition (PPI) of the startle reflex. It is conceivable that such deficits may hinder the cognitive functions in schizophrenia patients. In this study, using PPI and a neuropsychological battery, we studied this possibility in a group of 23 acute, neuroleptic-free schizophrenia patients and 16 controls. A non-significant decrease in PPI was found in the patients as compared to the controls, as well as significant differences in the performance of Trail A and B in Wisconsin Card Sorting and Digit/Symbol Tests. No statistically significant correlations between PPI and neuropsychological performance were found after the correction for multiple comparisons in any group. Our results suggest that PPI deficits in schizophrenia patients may not contribute to the cognitive deficits typical of that illness, at least in patients with a non-significant PPI decrease.

Prepulse Inhibition in HIV-Associated Neurocognitive Disorders

“…In individuals with schizophrenia however, where PPI has been proposed as an endophenotype of the disease, some studies show relationships between sensorimotor inhibition deficits and impaired cognition (Butler, Jenkins, Sprock, & Braff, 1992; Rabin, Sacco, & George, 2009), while others do not (Hasenkamp et al, 2011; Kishi et al, 2012; Molina et al, in press; N. R. Swerdlow et al, 2006).…”

“…It is not surprising that PPI deficits would be associated with impaired neurocognitive function (Geyer, 2006), and in healthy subjects higher sensorimotor inhibition has been related to better performance on neurocognitive tests of executive function (Bitsios et al, 2006; Giakoumaki et al, 2006) and working memory (Csomor et al, 2008). In individuals with schizophrenia, however, where PPI has been proposed as an endophenotype of the disease, some studies show relationships between sensorimotor inhibition deficits and impaired cognition (Butler, Jenkins, Sprock, & Braff, 1992; Rabin, Sacco, & George, 2009), while others do not (Hasenkamp et al, 2011; Kishi et al, 2012; Molina et al, 2010; Swerdlow et al, 2006). For example, in a well-powered study using multiple statistical methods, Swerdlow and colleagues found that schizophrenia patients with low PPI were not the same subjects that exhibited poor neuropsychological performance.…”

Prepulse Inhibition of the Auditory Startle Reflex Assessment as a Hallmark of Brainstem Sensorimotor Gating Mechanisms

“…Modifications of the PPI are very diverse and may be caused by neurological [ 59 ] or psychiatric diseases characterized by anxiety symptoms [ 60 , 61 ], behavioral states (such as emotional context or a stressor) [ 62 , 63 , 64 ], hormonal levels [ 37 , 65 , 66 ], and even adaptations derived from particularities of some professions, as occurs in the case of athletes [ 67 ]. All reflect various processes of neural plasticity, and it is striking that their sensitivity to sensory events happen a few milliseconds before the startle-eliciting stimulus.…”

Presidential Address 2014: The more‐or‐less interrupting effects of the startle response

“…PPI deficits have been observed across the schizophrenia spectrum in some (but not all) medicated and unmedicated patients (Anokhin, Heath, Myers, Ralano, & Wood, ; Braff et al, ; Greenwood et al, ), in relatives of patients, and in patients diagnosed with schizotypy (Cadenhead, Swerdlow, Shafer, Diaz, & Braff, ; Kumari, Das, Zachariah, Ettinger, & Sharma, ). Although hundreds of studies have looked at PPI and its deficiency in clinical conditions, PPI deficits are generally only weakly correlated with schizophrenic symptomatology (Hasenkamp et al, ; Molina et al, ; Swerdlow et al, ). This may be due to a heterogeneous patient population, or to variations in methodology across studies.…”