Studies of saccadic suppression and induced motion have suggested separate representations of visual space for perception and visually guided behavior. Because these methods required stimulus motion, subjects might have confounded motion and position. We separated cognitive and sensorimotor maps without motion of target, background, or eye, with an "induced Roelofs effect": a target inside an off-center frame appears biased opposite the direction of the frame. A frame displayed to the left of a subject's center line, for example, will make a target inside the frame appear farther to the right than its actual position. The effect always influences perception, but in half of our subjects it did not influence pointing. Cognitive and sensorimotor maps interacted when the motor response was delayed; all subjects now showed a Roelofs effect for pointing, suggesting that the motor system was being fed from the biased cognitive map. A second experiment showed similar results when subjects made an open-ended cognitive response instead of a five-alternative forced choice. Experiment 3 showed that the results were not due to shifts in subjects' perception of the felt straight-ahead position. In Experiment 4, subjects pointed to the target and judged its location on the same trial. Both measures showed a Roelofs effect, indicating that each trial was treated as a single event and that the cognitive representation was accessed to localize this event in both response modes.Several topographic maps represent the visual world in the cortex (Felleman & Van Essen, 1991). This characteristic of the visual system raises a question for visual physiology: do all of these maps work together to create a single representation of visual space, or are they functionally distinct? If they are distinct, how many functional maps are there and how do they communicate with one another? This paper presents psychophysical evidence for at least two functionally distinct representations of the visual world in normal humans; under some conditions, the two representations can simultaneously hold different spatial values. The paper also demonstrates some of the ways in which the representations communicate with one another.An early hint that cognitive and sensorimotor systems are separable in normal humans came from studies of eye movements. On the one hand, subjects are unaware ofsizable displacements of the visual world if they occur during saccadic eye movements, implying that information about spatial location is degraded during saccades (Bridgeman,

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A study was conducted in Santa Cruz County to estimate the prevalence and distribution of the agents of Lyme disease, human granulocytic (HGE), and human monocytic (HME) ehrlichiosis in 1,187 adult ixodid ticks collected from eight public-use recreation areas over a 2-yr period. Borrelia burgdorferi, the causative agent of Lyme disease, was detected by a polymerase chain reaction (PCR) in 44 of 776 (5.67%) Ixodes pacificus ticks and in 3 of 58 (5.17%) Dermacentor variabilis ticks. Anaplasma phagocytophilum, the causative agent of HGE, was detected by PCR in 48 (6.19%) I. pacificus ticks and 5 (8.62%) D. variabilis ticks. Ehrlichia chaffeensis, the causative agent of HME, was detected by nested PCR in just five (0.64%) I. pacificus ticks and four (6.9%) D. variabilis ticks. Interestingly, eight (1.03%) I. pacificus ticks were co-infected with B. burgdorferi and A. phagocytophilum, and just one (0.12%) tick was co-infected with B. burgdorferi and E. chaffeensis. Less than 1% of 353 Dermacentor occidentalis ticks showed evidence of infection with any of the agents tested. To our knowledge, this is the first reported identification of A. phagocytophilum and E. chaffeensis in D. occidentalis ticks from California This study represents the first extensive survey of Lyme and the ehrlichial diseases across multiple areas of Santa Cruz County, and suggests that prevalence of B. burgdorferi in Santa Cruz County may be higher than other areas of the state.

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A comprehensive understanding of spaceflight factors involved in immune dysfunction and the evaluation of biomarkers to assess in-flight astronaut health are essential goals for NASA. An elevated neutrophil-to-lymphocyte ratio (NLR) is a potential biomarker candidate, as leukocyte differentials are altered during spaceflight. In the reduced gravity environment of space, rodents and astronauts displayed elevated NLR and granulocyte-tolymphocyte ratios (GLR), respectively. To simulate microgravity using two well-established ground-based models, we cultured human whole blood-leukocytes in high-aspect rotating wall vessels (HARV-RWV) and used hindlimb unloaded (HU) mice. Both HARV-RWV simulation of leukocytes and HU-exposed mice showed elevated NLR profiles comparable to spaceflight exposed samples. To assess mechanisms involved, we found the simulated microgravity HARV-RWV model resulted in an imbalance of redox processes and activation of myeloperoxidase-producing inflammatory neutrophils, while antioxidant treatment reversed these effects. In the simulated microgravity HU model, mitochondrial catalase-transgenic mice that have reduced oxidative stress responses showed reduced neutrophil counts, NLR, and a dampened release of selective inflammatory cytokines compared to wildtype HU mice, suggesting simulated microgravity induced oxidative stress responses that triggered inflammation. In brief, both spaceflight and simulated microgravity models caused elevated NLR, indicating this as a potential biomarker for future in-flight immune health monitoring.

Murine immune profiles from simulated deep spaceflight conditions were analyzed Immune profiling revealed unique immune diversity with each experimental condition Plasma microRNA sequence analysis revealed involvement in immune system dysregulation Astronaut data showed elevated inflammation during low-Earth orbit missions

In human visual analysis, the initial processing of motion and chromatic signals may be mediated by feed-forward pathways from striate cortex to segregated areas of extrastriate cortex. The time-course of occipital to temporo-parieto-occipital motion processing was unknown, as was the selectivity of the effect of transcranial magnetic stimulation (TMS) on motion processing. TMS delivered over occipital cortex degraded the discrimination of motion-defined form (MDF) in a discrete time window beginning 100-120 ms from the onset of the visual stimulus. Bilateral focal TMS delivered over the temporo-parieto-occipital junction (TPO) disrupted the discrimination of MDF in a time window beginning 20-40 ms later than the effect of TMS delivered over occipital cortex. Bilateral focal TMS delivered over TPO also degraded the discrimination of CDF, motion direction, and color.