Bruce I Turetsky

..It is unclear, however, whether these behavioral abnormalities reflect basic olfactory sensory processing deficits or nonspecific disruptions of attention and cognition...

..Patients with schizophrenia exhibit olfactory deficits, but it is unclear whether these represent a specific abnormality. The link between olfactory impairments and regional brain abnormalities has yet to be established...

..We conclude with a discussion of the few studies thus far that have employed a multivariate approach with these candidates...

..It unambiguously demonstrates that neurophysiological disturbances in schizophrenia are not limited to cortical and subcortical structures, but rather include even the most peripheral sensory neurons...

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..This study examined olfactory bulbs in patients' relatives to determine whether low bulb volume represents an endophenotypic marker of genetic vulnerability...

..Our results offer a possible link between these two sets of findings, suggesting that some patients with schizophrenia may have dysfunctional noradrenergic systems...

..Unimpaired patients had fewer negative symptoms and dorsal medial prefrontal hypermetabolism. The authors conclude that categorizing patients on the basis of memory deficits may yield neurobiologically meaningful disease subtypes...

..We report initial results from the COGS dataset of auditory N100 amplitude and gating as candidate endophenotypes...

..The neural correlates of this dysfunction are unclear. Prior study has suggested that schizophrenia vocal affect perception deficits stem from an inability to use acoustic cues, notably pitch, in decoding emotion...

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..Cerebral activity underlying abnormal attention can be examined with event-related functional magnetic resonance imaging...

..Such multidimensional profiling of ERP abnormalities may help to clarify the clinical and genetic heterogeneity of schizophrenia...

..This could help to clarify underlying brain mechanisms and facilitate identification of clinically relevant biomarkers...

..Phenotypic variation in PTC sensitivity is thought to be genetic in origin and suggests greater illness risk for those subjects with recessive taster alleles...

..In schizophrenia, reduced modulation of OFC/VLPFC by context coupled with reduced behavioural efficiency suggests impaired ventral prefrontal control mechanisms that optimize affective appraisal...

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..Odor-detection thresholds to two odorants that differ in the degree to which they activate intracellular cAMP were assessed in clinical risk and low-risk participants...

..Neuropsychological studies have demonstrated verbal episodic memory deficits in schizophrenia during word encoding and retrieval. This study examined neural substrates of memory in an analysis that controlled for successful retrieval...

..This study examined intensity and hedonic judgments in patients with schizophrenia to determine whether these functions were differentially impaired...

..No significant associations between ApoE status and olfaction were observed in either diagnostic group. The authors concluded that olfactory deficits in schizophrenia do not appear to be mediated by the ApoE allele...

..Exploration of the genetic architecture of specific endophenotypes may be a powerful strategy for understanding the genetic basis of schizophrenia...

..This study suggests that olanzapine may help improve N100 impairments seen in schizophrenia, while haloperidol does not...

..Genetic studies now often employ multiple, geographically dispersed test sites to accommodate the need for large and complex study samples. Here, we assessed the feasibility of using PPI in multi-site studies...

..Frontotemporal abnormalities have been documented by using predetermined region-of-interest approaches, but deformation-based morphometry permits examination of the entire brain...

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..Future studies could use transcription profiling to clarify such interactions between genetic background, specific neuronal circuits, and transmitter systems...

..Age was associated with reduced peak HRF in left frontal region. Thus, indices of the HRF can be used to better understand the relationship between hemodynamic changes and performance and can be sensitive to individual differences...

..The correlations with symptom severity suggest that neuroanatomic abnormalities in OAR reflect compensatory brain changes...

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..Olfactory and emotion recognition abilities appear significantly linked in schizophrenia...

..The results of this study suggest that older adults may rely on different cortical networks to perceive emotional facial expressions than do their younger counterparts...

..Understanding the nature of these physiologic olfactory impairments could offer clues to the basic neuropathology of this disorder...

..The authors evaluated cerebral blood flow response in schizophrenia patients during facial emotion processing to test the hypothesis of diminished limbic activation related to emotional relevance of facial stimuli...

..The purpose of this article is to provide a description of the COGS structure and methods, including participant recruitment and assessment...

..Olfactory and orbital sulcal depths were correlated in controls, but not in patients. Olfactory sulcal depth may therefore be a biomarker denoting an early embryonic disruption in individuals at risk for schizophrenia...

..This study was designed to test this hypothesis by determining odor detection threshold sensitivities to two odorants that differ in their relative activations of this intracellular cAMP signaling cascade...

..This study examined event-related potential (ERP) responses to emotional faces in schizophrenia patients and controls to determine when, in the temporal processing stream, patient abnormalities occur...

..Findings are discussed in the context of existing literature regarding gender differences, hemispheric specialization, and the role of stimulus characteristics...

..Future studies will attempt to determine the cause of these differences in sensory and sensorimotor processing between these two closely related inbred mouse strains...

..Thus, the study provides impetus for future work in this area...

..The authors examined PTC sensitivity in schizophrenia patients and their non-ill relatives to determine whether this represented a vulnerability marker...

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..The PTC nontaster haplotype is a genetic marker that may be used to identify subsets of schizophrenia patients who potentially harbor vulnerability genes in this region of chromosome 7q...

..Future studies that examine the olfactory processing deficit in schizophrenia with respect to other olfactory measures and COMT haplotypes is warranted...

..This is manifest at a relatively early stage of visual processing and might relate to physiological disturbances in areas V3/V3a of the extrastriate cortex...

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..Impaired P50 gating is a putative index of genetically mediated nicotinic dysfunction in schizophrenia. However, assessment is confounded, in patients, by differential effects of smoking, symptoms, and treatment...

..These findings highlight the importance of accounting for intrinsic motivation and reward when studying cognitive tasks, and add to growing evidence of reward circuit dysfunction in schizophrenia that may impact cognition and function...

..These results support the central role of the amygdala in emotion processing, and indicate its sensitivity to the task relevance of the emotional display...

..We also examine odor valence processing unirhinally, rather than birhinally, to probe possible lateralized differences in patients' hedonic processing deficits...

..Because the olfactory system continuously regenerates throughout life, it allows for a unique view of an ongoing neurodevelopmental process...

..Results support fractal n-back validity and indicate substantial overlap in working memory functions of dorsal and ventral PFC...

..Nicotine alters auditory event-related potentials (ERPs) in rodents and humans and is an effective treatment for smoking cessation. Less is known about the effects of the partial nicotine agonist varenicline on ERPs...

..The ability to model novelty detection deficits in mice will aid in identifying genetic contributions to abnormal neuronal organization in people with schizophrenia...

..Thus, the biological changes commonly attributed to "aging" do, in fact, begin much earlier in the life-cycle...

..No relationship was observed between olfactory and semantic task performance in patients. These data suggest that odor identification deficits may not be primarily due to semantic processing deficits in schizophrenia...

..It highlights the importance, especially in patients with an incomplete medical history, of ruling out all organic causes of psychosis to avoid inappropriately labeling someone as having a psychiatric illness...

..These results confirm previous findings of antisaccade deficits in schizophrenia subjects and support the use of the antisaccade task as a potential schizophrenia endophenotype in multi-site genetic studies...

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