Effects of Aroma Massage on Home Blood Pressure, Ambulatory Blood Pressure, and Sleep Quality in Middle-Aged Women with Hypertension

The purpose of this study was to evaluate the effects of aroma massage applied to middle-aged women with hypertension. The research study had a nonequivalent control group, nonsynchronized design to investigate the effect on home blood pressure (BP), ambulatory BP, and sleep. The hypertensive patients were allocated into the aroma massage group (n=28), the placebo group (n=28), and the no-treatment control group (n=27). To evaluate the effects of aroma massage, the experimental group received a massage with essential oils prescribed by an aromatherapist once a week and body cream once a day. The placebo group received a massage using artificial fragrance oil once a week and body cream once a day. BP, pulse rate, sleep conditions, and 24-hour ambulatory BP were monitored before and after the experiment. There was a significant difference in home systolic blood pressure (SBP) (F=6.71, P=0.002) between groups after intervention. There was also a significant difference in SBP (F=13.34, P=0.001) and diastolic blood pressure (DBP) (F=8.46, P=0.005) in the laboratory between aroma massage and placebo groups. In sleep quality, there was a significant difference between groups (F=6.75, P=0.002). In conclusion, aroma massage may help improve patient quality of life and maintain health as a nursing intervention in daily life

P3-9: Roles of Subthreshold LFP Induced by Receptive Field Surround for Response Modulation in Monkey V1

A focal stimulus outside the receptive field robustly induces LFP change, while the same stimulus evokes no spike activity. We determined how this subthreshold LFP change interacted with spike response to the RF stimulus. Specifically, we sequentially presented two identical Gabor stimuli with a variable stimulus onset asynchrony (SOA); the first one (S1) was presented outside RF inducing a subthreshold LFP change, and the second one (S2) was subsequently presented within RF generating a spiking response. This enabled us to manipulate the temporal relation between subthreshold LFP and evoked spike activity and to determine whether subthreshold LFP contributed to modulation of spike activity in a SOA-dependent manner. We found that the subthreshold LFP propagated a considerably long distance, estimated to be more than 10 mm of cortical distance. The cross-correlation between the time course of subthreshold LFP and the pattern of SOA-dependency of spike activity was significant. These results indicate that signal integration is farther beyond the RF than previously estimated based on spike-triggered average, and suggest that subthreshold LFP modulate spike activity in a SOA-dependent manner

Covariation between Spike and LFP Modulations Revealed with Focal and Asynchronous Stimulation of Receptive Field Surround in Monkey Primary Visual Cortex.

A focal visual stimulus outside the classical receptive field (RF) of a V1 neuron does not evoke a spike response by itself, and yet evokes robust changes in the local field potential (LFP). This subthreshold LFP provides a unique opportunity to investigate how changes induced by surround stimulation leads to modulation of spike activity. In the current study, two identical Gabor stimuli were sequentially presented with a variable stimulus onset asynchrony (SOA) ranging from 0 to 100 ms: the first (S1) outside the RF and the second (S2) over the RF of primary visual cortex neurons, while trained monkeys performed a fixation task. This focal and asynchronous stimulation of the RF surround enabled us to analyze the modulation of S2-evoked spike activity and covariation between spike and LFP modulation across SOA. In this condition, the modulation of S2-evoked spike response was dominantly facilitative and was correlated with the change in LFP amplitude, which was pronounced for the cells recorded in the upper cortical layers. The time course of covariation between the SOA-dependent spike modulation and LFP amplitude suggested that the subthreshold LFP evoked by the S1 can predict the magnitude of upcoming spike modulation

Modulation of V1 spike response by temporal interval of spatiotemporal stimulus sequence.

The spike activity of single neurons of the primary visual cortex (V1) becomes more selective and reliable in response to wide-field natural scenes compared to smaller stimuli confined to the classical receptive field (RF). However, it is largely unknown what aspects of natural scenes increase the selectivity of V1 neurons. One hypothesis is that modulation by surround interaction is highly sensitive to small changes in spatiotemporal aspects of RF surround. Such a fine-tuned modulation would enable single neurons to hold information about spatiotemporal sequences of oriented stimuli, which extends the role of V1 neurons as a simple spatiotemporal filter confined to the RF. In the current study, we examined the hypothesis in the V1 of awake behaving monkeys, by testing whether the spike response of single V1 neurons is modulated by temporal interval of spatiotemporal stimulus sequence encompassing inside and outside the RF. We used two identical Gabor stimuli that were sequentially presented with a variable stimulus onset asynchrony (SOA): the preceding one (S1) outside the RF and the following one (S2) in the RF. This stimulus configuration enabled us to examine the spatiotemporal selectivity of response modulation from a focal surround region. Although S1 alone did not evoke spike responses, visual response to S2 was modulated for SOA in the range of tens of milliseconds. These results suggest that V1 neurons participate in processing spatiotemporal sequences of oriented stimuli extending outside the RF

Response Modulation of V1 Neurons by Spatiotemporal Sequence of Oriented Stimuli

Spike activity of V1 neurons in response to natural scene (Vinje and Gallant, 2002; Montemurro et al., 2008; Haider et al., 2010) is surprisingly consistent across repeated trials. While it is clear that these responses are not explained by classical receptive field (cRF) properties, it is not known how surround interaction increases the selectivity of V1 response. Put more generally, we do not completely understand the mapping rules between elementary features of visual scene and V1 activity. In the current study we examined the possibility that V1 neurons are selective for spatiotemporal sequence of oriented stimuli. We will describe a novel response property of monkey V1 neurons that visual response was modulated depending on the stimulus onset asynchrony (SOA) in the range of tens of milliseconds between two sequentially presented Gabor stimuli. The preceding stimulus (S1) was presented outside cRF and the following one (S2) inside cRF. S1 alone did not evoke spike response but modulated cell's response to S2. Spike response to S2 was not constant across SOA, and the SOA associated with maximal response modulation varied with the position of S1. These results suggest that V1 neurons are selective for spatiotemporal sequence of oriented stimuli based on surround interaction

Deviation of LFP from linear sum in the representative cell of Fig 3.

<p><b>A.</b> Shown are LFP traces in an arbitrary unit for each SOA condition derived by the mean LFP traces observed during S1-S2 sequence stimulation minus the SOA-adjusted linear sum of S1-evoked LFP and S2-evoked LFP. <b>B.</b> Deviation of LFP in RMS power. Each colored symbol represents the mean deviation across SOA conditions for each of 30 cells shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0144929#pone.0144929.g005" target="_blank">Fig 5</a>. Black symbols represent their mean values with 1SEs.</p

Spike and LFP activity of a representative cell.

<p><b>A</b>. Spatial layout of stimulus configuration: the cross marks the fixation target; the dashed white circle(invisible to the animal) shows the boundary of the RF; the calibration bar indicates 1°. The RF was centered 3.3° right and 4.2° down. Two Gabor stimuli, one at the RF (S2), and the other in the RF surround (S1) are shown. <b>B, C</b>. Raster and spike density plots (B) and mean LFP traces (C) in response to S2 alone (upper) and S1 alone (lower), aligned at their onset times (dashed vertical line). Shadings in C indicate ±2 SE. Y-axis indicates spike density in spikes/s in B, and LFP amplitude in mV in C. Note that a robust LFP change was recorded in response to S1 alone, while the cell did not discharge spikes. <b>D</b>. SOA time plot for response modulation during trials with S1-S2 sequence stimuli, showing spike activity as a function of SOA and time, aligned at S2 onset. Activity is coded by color, as indicated by the calibration bar at top. White dots indicate the time of S1 onset for each SOA condition. The spike density for the S2-alone condition is given in a separate color map at bottom for comparison. Note that depending on SOA, spike density varied considerably in terms of magnitude and time course. Spike density for an SOA of 70 ms is indicated by the blue horizontal line, whereas the reference density for S2 alone (at bottom) is indicated by the horizontal black line; the time courses of both are shown in the upper panel of E with the same color coding. <b>E, F.</b> Upper: Spike (E) and LFP activity (F) in response to S1-S2 sequence stimuli with an SOA of 70 ms (blue), aligned at the time of S2 onset (dashed vertical lines). In each panel, a black trace indicates the reference of the S2-alone condition. Shadings indicate ±2 SE. Lower: The magnitude of modulation (S1-S2 sequence minus S2-alone) in firing rate (E) or LFP (F) is plotted for the SOA of 70 ms.</p

Effects of S1 on spike (A) and LFP (B) response across 11 SOA conditions.

<p>Each colored symbol represents the mean magnitude of spike (A) or LFP (B) response in percentage with respect to S2-alone condition for corresponding SOA condition of each of 30 cells for which nearest S1 was tested. Black symbols represent median values of those means with 1SEs. Percent modulations less than 100 indicate suppression and those larger than 100 indicate facilitation by addition of S1.</p