When top-down meets bottom-up: auditory training enhances verbal memory in schizophrenia.
ABSTRACT A critical research priority for our field is to develop treatments that enhance cognitive functioning in schizophrenia and thereby attenuate the functional losses associated with the illness. In this article, we describe such a treatment method that is grounded in emerging research on the widespread sensory processing impairments of schizophrenia, as described elsewhere in this special issue. We first present the rationale for this treatment approach, which consists of cognitive training exercises that make use of principles derived from the past 2 decades of basic science research in learning-induced neuroplasticity; these exercises explicitly target not only the higher order or "top-down" processes of cognition but also the content building blocks of accurate and efficient sensory representations to simultaneously achieve "bottom-up" remediation. We then summarize our experience to date and briefly review our behavioral and serum biomarker findings from a randomized controlled trial of this method in outpatients with long-term symptoms of schizophrenia. Finally, we present promising early psychophysiological evidence that supports the hypothesis that this cognitive training method induces changes in aspects of impaired bottom-up sensory processing in schizophrenia. We conclude with the observation that neuroplasticity-based cognitive training brings patients closer to physiological patterns seen in healthy participants, suggesting that it changes the brain in an adaptive manner in schizophrenia.
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ABSTRACT: This study aimed to compare the effects of a non-linguistic auditory intervention approach with a phonological intervention approach on the phonological skills of children with speech sound disorder (SSD). A total of 17 children, aged 7-12 years, with SSD were randomly allocated to either the non-linguistic auditory temporal intervention group (n = 10, average age 7.7 ± 1.2) or phonological intervention group (n = 7, average age 8.6 ± 1.2). The intervention outcomes included auditory-sensory measures (auditory temporal processing skills) and cognitive measures (attention, short-term memory, speech production, and phonological awareness skills). The auditory approach focused on non-linguistic auditory training (e.g., backward masking and frequency discrimination), whereas the phonological approach focused on speech sound training (e.g., phonological organization and awareness). Both interventions consisted of 12 45-min sessions delivered twice per week, for a total of 9 h. Intra-group analysis demonstrated that the auditory intervention group showed significant gains in both auditory and cognitive measures, whereas no significant gain was observed in the phonological intervention group. No significant improvement on phonological skills was observed in any of the groups. Inter-group analysis demonstrated significant differences between the improvement following training for both groups, with a more pronounced gain for the non-linguistic auditory temporal intervention in one of the visual attention measures and both auditory measures. Therefore, both analyses suggest that although the non-linguistic auditory intervention approach appeared to be the most effective intervention approach, it was not sufficient to promote the enhancement of phonological skills.Frontiers in Psychology 01/2015; 6:64. DOI:10.3389/fpsyg.2015.00064 · 2.80 Impact Factor
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ABSTRACT: In schizophrenia, perceptual inundation related to sensory gating deficit can be evaluated "off-line" with the sensory gating inventory (SGI) and "on-line" during listening tests. However, no study investigated the relation between "off-line evaluation" and "on-line evaluation". The present study investigates this relationship. A sound corpus of 36 realistic environmental auditory scenes was obtained from a 3D immersive synthesizer. Twenty schizophrenic patients and twenty healthy subjects completed the SGI and evaluated the feeling of "inundation" from 1 ("null") to 5 ("maximum") for each auditory scene. Sensory gating deficit was evaluated in half of each population group with P50 suppression electrophysiological measure. Evaluation of inundation during sound listening was significantly higher in schizophrenia (3.25) compared to the control group (2.40, P<.001). The evaluation of inundation during the listening test correlated significantly with the perceptual modulation (n=20, rho=.52, P=.029) and the over-inclusion dimensions (n=20, rho=.59, P=.01) of the SGI in schizophrenic patients and with the P50 suppression for the entire group of controls and patients who performed ERP recordings (n=20, rho=-.49, P=.027). An evaluation of the external validity of the SGI was obtained through listening tests. The ability to control acoustic parameters of each of the realistic immersive environmental auditory scenes might in future research make it possible to identify acoustic triggers related to perceptual inundation in schizophrenia. Copyright © 2015. Published by Elsevier Masson SAS.European Psychiatry 02/2015; DOI:10.1016/j.eurpsy.2015.01.005 · 3.21 Impact Factor
Article: Nicotinic receptors and attention.[Show abstract] [Hide abstract]
ABSTRACT: Facilitation of different attentional functions by nicotinic acetylcholine receptor (nAChR) agonists may be of therapeutic potential in disease conditions such as Alzheimer's disease or schizophrenia. For this reason, the neuronal mechanisms underlying these effects have been the focus of research in humans and in preclinical models. Attention-enhancing effects of the nonselective nAChR agonist nicotine can be observed in human nonsmokers and in laboratory animals, suggesting that benefits go beyond a reversal of withdrawal deficits in smokers. The ultimate aim is to develop compounds acting with greater selectivity than nicotine at a subset of nAChRs, with an effects profile narrowly matching the targeted cognitive deficits and minimizing unwanted effects. To date, compounds tested clinically target the nAChR subtypes most abundant in the brain. To help pinpoint more selectively expressed subtypes critical for attention, studies have aimed at identifying the secondary neurotransmitter systems whose stimulation mediates the attention-enhancing properties of nicotine. Evidence indicates that noradrenaline and glutamate, but not dopamine release, are critical mediators. Thus, attentionAttention -enhancing nAChR agents could spare the system central to nicotine dependence. Neuroimaging studies suggest that nAChR agonists act on a variety of brain systems by enhancing activation, reducing activation, and enhancing deactivation by attention tasks. This supports the notion that effects on different attentional functions may be mediated by distinct central mechanisms, consistent with the fact that nAChRs interact with a multitude of brain sites and neurotransmitter systems. The challenge will be to achieve the optimal tone at the right subset of nAChR subtypes to modulate specific attentional functions, employing not just direct agonist properties, but also positive allosteric modulation and low-dose antagonism.