2008 Sep 05;8(9):5516-5534 The carbon-fiber and reference electrodes were connected to a voltammetric amplifier mounted near the rat's head at the base of the tether. Right, The behavior counts from the associated left panels were pooled into before (Pre; white bars) and after (Post; gray bars) totals. Meditation DNA Repair Happiness Frequency 432 Hz. Calming music for a happy life. Comparisons of the frequency (number of transients per minute) of the dopamine concentration transients in different experimental conditions were made with a Poisson distribution regression model with repeated measures. Correspondence should be addressed to Dr. R. Mark Wightman, Department of Chemistry, University of North Carolina, Chapel Hill, NC 27599-3290. Overall, phasic dopamine activity appeared to be associated with input from multiple sensory modalities and was followed by a variety of approach and appetitive behaviors, consistent with electrophysiological observations of dopaminergic neuron burst-firing. Histogram of dopamine concentration transients during the brief conspecific interaction episodes. Gating of information flow within the limbic system and the pathophysiology of schizophrenia. Like burst firing (Overton and Clark, 1997), the dopamine transients observed in the presence of conspecifics were apparently triggered by stimuli communicated through various sensory modalities. This is shown by the overlap of the cyclic voltammograms with one recorded in this animal during the electrical stimulation of the dopaminergic pathway (dotted line, scaled to size). The [DA]max was 190 ± 20 nm (range, 90–330), and the average duration was 390 ± 30 msec (range, 300–600). A high-throughput algorithm within the LabVIEW collection and analysis program was used to target potential dopamine concentration transients for additional investigation. Indeed, the naturally occurring concentration transients reported here closely resemble dopamine release during high-frequency stimulation of dopaminergic neurons (Robinson et al., 2001). It is currently unclear whether STN neurons have a preference for beta-frequency input (12-35 Hz), rather than cortical input at other frequencies, and how such a preference would arise following dopamine depletion. Comparison of uptake of dopamine in rat striatal chopped tissue and synaptosomes. Although basal concentrations cannot be measured with this technique, transient concentration changes are readily discerned, as seen in the middle of the figure. The frequency of the transients was low during solitude and copulation and increased dramatically during brief conspecific interaction, particularly at the introduction of the conspecific to the test chamber. Predictive reward signal of dopamine neurons. ), and National Institute on Alcohol Abuse and Alcoholism Training Grant AA07573 (D.L.R.). To validate these targets as dopamine transients, the background-subtracted cyclic voltammograms at the targeted times were compared with those for dopamine. B, Cyclic voltammograms corresponding to the electrochemical signal at the times indicated by the arrows. Functional analysis of masculine copulatory behavior in the rat. Dynamic changes in nucleus accumbens dopamine efflux during the Coolidge effect in male rats. Dopamine concentration transients were continuously monitored throughout the solitary and conspecific episodes. Quantitative microdialysis of neurotransmitters. Although there was no significant interaction between the brain region and the presentation set, the main effect of the set was significant (z1 = 4.01; p < 0.0001), indicating that the frequency of transients decreased by 60% during the second presentation set. Thus, unlike previous reports of “dopamine-like signals,” the transients shown here are attributable to dopamine released into the extracellular space. Rebec et al. The guide cannula was positioned 1.2 mm anterior and 2 mm lateral to bregma and extended 2.5 mm below the skull surface; all recordings were made on the right side of the brain. The role of nucleus accumbens dopamine in motivated behavior: a unifying interpretation with special reference to reward-seeking. Behavioral correlates of dopaminergic unit activity in freely moving cats. A second transient occurred as the male made whisker contact with the female (Fig. Epub 2007 Dec 4. 2B) (main effect of episode, z1 = 3.87, p> 0.0001). Thus, although dopamine transients were seen in each brain region tested, they were most common in the NA and OT. USA.gov. In the NA, dopamine transients were observed as frequently with receptive as with nonreceptive females, but significantly less often with males (males vs receptive females,z1 = −2.38, p < 0.05; males vs nonreceptive females,z1 = −2.35, p < 0.05). Five of these transients were observed in the 2–5 sec before the intromission, whereas the remaining six occurred within 1 sec. S10A), and enhanced dopamine release by 2 pulses at 20 Hz but did not enhance dopamine release by 30 pulses at 20 Hz (fig. Transients from all striatal regions and all interaction episodes were pooled into 2 sec bins, with the introduction of the conspecific at time 0. Tonic dopamine results in low concentrations that are readily sampled by microdialysis and convey information through high-affinity receptors (Richfield et al., 1989). However, based on quantitative microdialysis calibrations (Justice, 1993), the concentration changes observed in those experiments were <100 nm and existed for a prolonged period (tens of minutes). The recording sites for the 17 male rats are illustrated in Figure1. The tether extended to a swivel at the top of the Faraday cage, allowing the rat full access to the test chamber. Left, Behaviors were scored for 5 sec before (white bars) and 5 sec after (gray bars) the start of each dopamine transient; the transient occurred at time 0. The electrochemical scans confirmed to be dopamine by the cyclic voltammograms are indicated byopen circles. Results and Conclusions: DAergic neuromodulation elicited frequency- and stimulus dependent power changes in the recorded LFPs. We recently measured phasic dopamine signals in the context of sexual behavior (Robinson et al., 2001) and observed transient, robust increases in extracellular dopamine in the NA core of male rats on initial exposure to receptive female rats and subsequent approach behaviors. Frequency (Hz) Normalized Ca influx 250 ms ROI 5 5% F/F X 500 ms 50 100 150 1.0 1.2 1.4 ROI 1 ROI 2 ROI 3 ROI 4 ROI 5 *** 250 ms ROI 3 10% F/F 40% F/F B C D F G Frequency (Hz… 1 Rabbit retinal pieces were incubated with [3H]‐dopamine and superfused with Krebs solution. Comparisons of transient duration and [DA]max were made with a gamma distribution regression model with repeated measures. This sequence was followed by the male initiating sniffing of the female. The compiled behavior of the test rats 5 sec before and after each dopamine transient during the copulation episode is shown in Figure7. NIH The rats that engaged in copulation during the copulation phase exhibited 5 ± 1 simple mounts with an 8 ± 2 sec latency to mount and 7 ± 1 intromissions with a 56 ± 37 sec latency to intromit and a 20 ± 2 sec inter-intromission interval. Anatomical and affinity state comparisons between dopamine D1 and D2 receptors in the rat central nervous system. In contrast, significant habituation did not occur within the first presentation set. National Center for Biotechnology Information, Unable to load your collection due to an error, Unable to load your delegates due to an error. Moreover, some dopamine transients were associated with sniffing the conspecific, providing olfactory or tactile input. 2019 Jul;236(7):2211-2222. doi: 10.1007/s00213-019-05215-1. Second, recordings were made in anatomical sites selected because they supported robust dopamine release during electrical stimulation of the ascending dopaminergic processes. As fast voltammetric measurements are made in a variety of situations, the nature of phasic dopamine activity in the striatum will be revealed. Histology. The frequency of dopamine concentration transients was sixfold greater during episodes with conspecifics compared with solitary episodes (Fig.2A). Behavioral functions of nucleus accumbens dopamine: empirical and conceptual problems with the anhedonia hypothesis. The x-axis shows seconds before and after the dopamine transient; the z-axis displays various behaviors. Differential actions of endogenous and iontophoretic dopamine in rat striatum. Two-thirds of the transients observed during copulation were related to sexual behaviors, and the majority of these preceded consummatory aspects. What is the role of dopamine in reward: hedonic impact, reward learning, or incentive salience? Adrenal - An organ located above the kidneys - it manufactures a natural steroid called cortisol, which is associated with stress.. Amygdala - This is a pair of structures that exist an inch or so in from the forehead - there's one on the right side and one on the left side - they supposedly have an impact on moods. These results establish for the first time that transient dopamine fluctuations occur throughout the dorsal and ventral striatum and demonstrate that they are more frequent with salient stimuli that elicit a response behavior. During these episodes, 125 dopamine concentration transients from 17 rats were detected with fast-scan cyclic voltammetry at carbon-fiber microelectrodes (peak amplitude, 210 ± 10 nm; duration, 530 ± 20 msec). Unfortunately, fast-scan cyclic voltammetry cannot monitor slow changes in dopamine, and thus cannot address tonic changes. Addiction, dopamine, and the molecular mechanisms of memory. The entire experiment was videotaped with a camera mounted in the Faraday cage. Applying that approach results in a frequency range of 151.5 Hz to 152.2 Hz. Efflux of dopamine from the synaptic cleft in the nucleus accumbens of the rat brain. On the time scale of minutes, dopamine concentrations increase during sexual behavior, as measured with microdialysis (Pfaus et al., 1990; Pleim et al., 1990; Fiorino et al., 1997; Lorrain et al., 1999). Introduction Studies have shown activity reflected in the low (< 20 Hz) and high-frequency oscillations (> 50 Hz) dissociates from the activity of the middle-frequency band (18-38 Hz). As the female entered the test chamber (Fig. 2019;19(16):1365-1380. doi: 10.2174/1568026619666190712210903. Nicotine (500 nM) induced a decrease in dopamine efflux at low frequency (single pulse or five pulses at 10 Hz) and an increase at high frequency (100 Hz) electrical field stimulation. Regina Carelli, Paul Garris, and Paul Phillips for helpful discussions. We thank Megan Austin, Jessica Cantley, Lori Durham, Lisa Gurdin, Collin McKinney, and Sophia Papadeas for technical assistance, and Drs. Subsequent pairwise comparisons showed that in the CP, the frequency of dopamine signals with a receptive female present were marginally higher than with a male (z1 = 1.90; p < 0.058) and significantly higher than with a nonreceptive female (z1 = 2.26; p < 0.05). The signals observed during solitude, which are presumably distinct from environmental cues, may arise from bursts similar to those observed in anesthetized animals (Grace and Bunney, 1980). On the second presentation set, the signal habituated, suggesting that novelty or expectation contributed to the incidence of dopamine transients.  |  All rats were well handled by the experimenter. Surgery. The electrochemical and behavioral data were synchronized with a video character generator (Chemistry Instrument Facility, University of North Carolina) that superimposed the episode and electrochemical scan numbers on the video record. The stimulating electrode was positioned at the medial forebrain bundle (4.1 mm posterior and 1.4 mm lateral to bregma; ∼8 mm ventral from the skull surface) or the substantia nigra/ventral tegmental area (5.6 mm posterior and 1 mm lateral to bregma; ∼9 mm ventral from the skull surface) to stimulate dopaminergic fibers. The proximity to dopamine terminals was confirmed by the detection of electrically evoked dopamine release (24 rectangular pulses, 60 Hz, 120 μA, 2 msec/phase, biphasic). 2012 Jul 12;75(1):58-64 NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. Habituation may also contribute to the lower frequency of dopamine signals during copulation. Thus, each male received six brief conspecific presentations, interspersed with solitary episodes. The role of dopamine, especially in reward, has received extensive theoretical consideration (Wise and Rompre, 1989; Salamone et al., 1997; Berridge and Robinson, 1998; Ikemoto and Panksepp, 1999; Berke and Hyman, 2000). Criteria included peaks at approximately +0.6 and −0.2 V versus Ag/AgCl, their relative amplitude, the absence of extraneous peaks, and a minimum of at least two consecutive scans. Although dopamine transients were more frequent in the ventral striatum, the overall characteristics of the signals were remarkably similar among striatal regions. Frequency of dopamine concentration transients during brief conspecific episodes: effects of presentation set and conspecific rat. (3) Results: DA concentration and striatal neuron spike firing rate showed a similar change as DBS frequency changed from 10 to 350 Hz. 2C), because transients observed during conspecific episodes were 50% larger than those observed during solitary episodes (main effect of episode,z1 = 2.73, p > 0.01). Find NCBI SARS-CoV-2 literature, sequence, and clinical content: https://www.ncbi.nlm.nih.gov/sars-cov-2/. “Dismount” was defined as the time from when the male's forelimbs splayed to the conclusion of the jump away from the female and lasted 100–200 msec. Experimental design. Doing a sweep of the range from 151.3 Hz to 152.3 Hz might then target all of the virus variants nicely. Thank you for sharing this Journal of Neuroscience article. Please enable it to take advantage of the complete set of features! This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Clipboard, Search History, and several other advanced features are temporarily unavailable. o Too little of the alpha wave can present itself as a person who is highly stressed, anxiety-ridden, suffers from insomnia or … A template of the subtracted cyclic voltammogram for dopamine for each particular animal was selected from the electrochemical response during the electrical stimulation of dopamine neurons. The number of transients observed in each rat ranged from 0 to 3, with a mean of 1.3 ± 0.3 and a median of 1. With FSCV, the potential is ramped up from a holding potential to a switching potential and back, usually at a 400 V s −1 scan rate and a frequency of 10 Hz. The carbon fiber was acutely inserted with a detachable micromanipulator (Chemistry Instrument Facility, University of North Carolina) that locked into the guide cannula and allowed ventral placement of the electrode into the CP, NA, or OT at <0.1 mm increments. Close. O'Neill C, Nolan BJ, Macari A, O'Boyle KM, O'Connor JJ. Chris Wiesen at the Odum Institute for Research in Social Science provided invaluable statistical guidance. However, the number of transients was fewer in the presence of males compared with females, suggesting that a difference in biological salience also contributes to these signals. 2018 Jan 15;336:145-150. doi: 10.1016/j.bbr.2017.08.026. 2018 Jul 18;38(29):6597-6607. doi: 10.1523/JNEUROSCI.0071-18.2018. We do not retain these email addresses. This placement allowed insertion of the carbon-fiber microelectrode into the CP (4–5.5 mm ventral from the skull surface), NA (6–8.4 mm ventral), or OT (8.8–9.2 mm ventral). These include the unexpected presentation of rewards (Romo and Schultz, 1990; Mirenowicz and Schultz, 1996), conditioned stimuli (Mirenowicz and Schultz, 1994), discriminative stimuli (Miller et al., 1981), and novelty (Steinfels et al., 1983; Freeman and Bunney, 1987; Ljungberg et al., 1992). Lateral hypothalamic serotonin inhibits nucleus accumbens dopamine: implications for sexual satiety. During spontaneous activity, we observed a remarkable increase specific to the middle-frequency (18 – 38 Hz) band power accompanied by a decrease of gamma (50 – 150 Hz… The power spectrum between 0.1 and 30 Hz was transformed using the “mtspecgramc” function in the MATLAB signal processing toolbox chronux_2_12 (MathWorks, USA). Dopamine D1 receptor; Dopamine release; Fast cyclic voltammetry; Nicotine; SCH-23390; SKF-38393. The dorsal and ventral striatum were divided into three broad regions: CP, NA, and OT. In theleft panels, the y-axis designates the counts of particular behaviors, with the maximum value as the number of dopamine transients observed in the respective striatal region; thus, it is readily apparent that no one behavior was associated with every transient. Transients in the NA were significantly associated with increases in general sniffing and orienting movements, as well as approach to and sniffing the conspecific; *p < 0.05, before versus after. The majority of transients occurred before the consummatory aspect of intromission (i.e., thrusting). (A1) Depth profile of the field response evoked by layer I–II stimulation, following Morris et al. Prolonged and extrasynaptic excitatory action of dopamine mediated by D1 receptors in the rat striatum. Ramps down to 7.5 Hz and remains until 15 minutes. In the NA, other behaviors were also increased after the dopamine transient. SfN does not assume any responsibility for any injury and/or damage to persons or property arising from or related to any use of any material contained in JNeurosci. Frequency: 9.0 Hz for 12 minutes, then ramps down slowly to 2.5 Hz and remains until 27 minutes. The present results are consistent with current theories of phasic dopamine function, but the precise causes and consequences of the extrasynaptic signals require additional exploration. Gómez-A A, Shnitko TA, Barefoot HM, Brightbill EL, Sombers LA, Nicola SM, Robinson DL. The effect of nicotine induced behavioral sensitization on dopamine D1 receptor pharmacology: An in vivo and ex vivo study in the rat. The frequency of dopamine transients was highest at the initial presentation of females. Importance of unpredictability for reward responses in primate dopamine neurons. Voltammetric measurements. Females were induced to behavioral estrus by the injection of 10 μg of estradiol benzoate 48 hr before and 500 μg of progesterone 4 hr before testing. 6, right). If left ear gets 82 hz frequency and right ear 92 Hz, then we have 10 Hz binaural beat ( alpha waves ). First, dopamine transients were identified by computer-matching of the voltammograms and verified subsequently by human inspection. Active dopamine neurons fire at approximately 5 Hz under normal conditions, but exhibit sub‐second duration bursts of high frequency firing at approximately 20 Hz (Clark and Chiodo 1988), which correlates with reward‐based events (Schultz and Romo 1990). Tonic and phasic dopamine neurotransmission, each causing different changes in dopamine extracellular concentrations, may play distinct functional roles that influence behavior. For statistical analysis, the total count for each behavior in the 5 sec before a transient was compared with the count 5 sec after the transient. A, Habituation of transients during the second presentation set, by brain region; *p < 0.0001. Abundance Meditation. The oxidative and reductive peaks of the dopamine transients are compared with those of dopamine obtained during the electrical stimulation of the dopamine fibers (dotted line, scaled to size). Transient, elevated concentrations of extracellular dopamine were characterized in the dorsal and ventral striatum of male rats during solitude, brief interaction with a conspecific, and copulation. Posted by 3 years ago. Considerable evidence indicates that dopamine systems in the forebrain contribute to various aspects of reinforced behavior (Wise and Rompre, 1989). However, the phasic dopamine activity habituated on the second presentation of the conspecifics. The present results characterize dopamine concentration transients in multiple brain regions of male rats during biologically relevant situations. The overall frequency of dopamine transients during copulation was 0.17 ± 0.05 per minute, which is 20% of that during the brief conspecific episodes and 120% of that during the solitary episodes. The first dopamine transient coincided with the entrance of the female to the test chamber and was followed by immediate orientation of the male toward the female. Interestingly, 26% of the transients occurred 5 sec before and after the introduction of the receptive female. In addition, copulatory behavior was evaluated by the construction of an event record of mounts (simple and ectopic), intromissions, ejaculations, genital grooming, and 22 kHz vocalizations (Sachs and Barfield, 1976). In this role, phasic dopamine participates not only in associative learning but more broadly in response facilitation (Oades, 1985; Salamone et al., 1997; Ikemoto and Panksepp, 1999). The role of noradrenaline in tuning and dopamine in switching between signals in the CNS. 2015 Aug 15;593(16):3513-32 Uptake of dopamine released by impulse flow in the rat mesolimbic and striatal systems in vivo. In summary, (1) dopamine concentration transients occur in awake rats during solitude, in the absence of overt external cues; (2) dopamine transients are significantly more frequent in the presence of a conspecific, although this effect habituates; and (3) dopamine transients are less frequent during copulation than during brief conspecific episodes. The exposed fiber was trimmed to 130–225 μm from the glass seal. Such firing patterns should cause discrete chemical surges of dopamine into the extrasynaptic space, lasting for 1 or 2 sec (Kawagoe et al., 1992; Suaud-Chagny et al., 1995). Instrumentation: Tuned to 528 Hz (the love frequency) to promote inner peace and awaken imagination. The frequency of dopamine transients within conspecific episodes was found to decrease during the second presentation set, indicating habituation of dopamine transients (Fig.5A). The phasic dopamine response to a conspecific habituated with a second encounter. The duration of dopamine transients was determined from the cyclic voltammograms examined on a scan-by-scan basis. After the conspecific and solitary episodes, the test rat was left undisturbed for 10 min before voltammetric data collection resumed. Representation of the carbon-fiber microelectrode recording sites in the dorsal and ventral striatum, as constructed from histological sections. (B) Three-Hz stimuli (15 min) induced LTD of the layer I–II response. Transient changes in mesolimbic dopamine and their association with “reward.”. Traditionally, nigrostriatal dopamine is viewed as necessary for sensorimotor coordination, and mesolimbic dopamine is viewed as necessary for appetitive and motivational aspects. The chemical signal was not observed in the NA core, nor was it observed on subsequent reentry. The frequencies of dopamine transients (per minute, pooled across striatal regions) during the individual conspecific episodes were: first, 1.1 ± 0.3; second, 1.4 ± 0.3; third, 1.1 ± 0.3; fourth, 0.6 ± 0.1; fifth, 0.4 ± 0.1; and sixth, 0.4 ± 0.1. Thus, we were surprised at the lack of variation in the amplitude and duration of the measured signals among regions. Before presentation, the male was sitting quietly on an absorbent pad in the chamber and the concentration changes stayed within the noise level (Fig. They reached concentrations similar to theKm for the dopamine transporter (∼200 nm) (Near et al., 1988), sufficient to interact with some low-affinity receptors (Richfield et al., 1989), and lasted for only ∼0.5 sec. General sniffing increased in 60% of the transients (z1 = 2.51;p < 0.05), orienting behaviors increased in 60% (z1 = 3.38; p < 0.001), and locomotion to the rat increased in 30% (z1 = 2.59; p < 0.01). Electrochemical data were collected throughout the copulation period and for 2–4 min after ejaculation. With 70% of the transients in the CP, 50% of those in the NA, and 40% of those in the OT, sniffing of the conspecific increased after the transient (CP,z1 = 2.28, p < 0.05; NA, z1 = 2.42, p < 0.05; OT, z1 = 1.94, p< 0.053). Conspecifics (receptive female, nonreceptive female, and male) were presented one at a time to the test male rat in random order and allowed to interact with the test rat for 30 sec. Interestingly similar results were obtained with the D1R antagonist SCH-23390. Mesencephalic dopaminergic unit activity in the behaviorally conditioned rat. Sign In to Email Alerts with your Email Address, Frequency of Dopamine Concentration Transients Increases in Dorsal and Ventral Striatum of Male Rats during Introduction of Conspecifics. Burst firing in midbrain dopaminergic neurons. A total of 15 dopamine concentration transients were detected in the 12 rats that copulated. Schultz (1998) proposed that phasic firing of dopaminergic neurons predicts reward in reinforcement learning from studies on firing during associative learning in primates. Happiness Frequency - Serotonin, Dopamine and Endorphin Release Music, Binaural Beats Relaxing Music. The frequency of the α-bicoherence peak was simultaneously shifted to the lower frequency; from 11.5 (11.0, 13.0) to 10.5 (10.0, 11.0) Hz (median [25th, 75th percentiles], P < 0.0001). Moreover, two-thirds of the dopamine transients were followed by increases in sexual behavior (z1 = 3.78; p < 0.001). Third, we demonstrated previously that the duration and the number of transients increase after pharmacological inhibition of dopamine uptake (Robinson et al., 2001). E-mail: rmw{at}unc.edu. Moreover, the habituation was not attributable to an altered response of the carbon-fiber electrode or to an inability of the surrounding tissue to support transients, because the amplitude of electrically evoked dopamine signals did not change across the experiment (paired t test; p > 0.05; data not shown). Goutier W, O'Connor JJ, Lowry JP, McCreary AC. Preferential activation of midbrain dopamine neurons by appetitive rather than aversive stimuli. Nicotine Tob Res. The D1R agonist SKF-38393, whilst having no effect on dopamine release on its own or on the effect of nicotine upon multiple pulse evoked dopamine release, did significantly prevent and reverse the effect of nicotine on single pulse dopamine release. We presented each conspecific (male, receptive female, and nonreceptive female) twice to evaluate whether the dopamine response habituated as predicted for the role of phasic dopamine as an alerting signal (Schultz, 1998; Redgrave et al., 1999). Sexual behavior enhances central dopamine transmission in the male rat. Right, The behavior counts from the associated left panels were pooled into before (Pre; white bars) and after (Post; gray bars) totals. Rats were allowed at least 3 hr to habituate to the cage and the tether on the experiment day. Conspecific rats were systematically presented to male rats and allowed to interact for 30 sec; the males were kept in solitude between each presentation. When males were allowed to copulate with receptive females, additional dopamine transients were observed at frequencies ∼20% of those during the previous interaction episodes. These changes may reflect a variation in the low-frequency tonic firing of dopaminergic neurons or glutamatergic actions at dopaminergic terminals (Grace, 2000). Rats were administered a lethal dose of urethane and perfused through the heart with saline and a 10% formalin solution. The durations of transients in this example are 0.8 sec (middle) and 0.4 sec (right); the electrochemical scans confirmed to be dopamine are shown by open circles. The conspecific rats were presented by gently pushing them over the lip of the test chamber and were manually removed after 30 sec. Publication of an advertisement or other product mention in JNeurosci should not be construed as an endorsement of the manufacturer’s claims. 2019 Apr 17;10(4):1935-1940. doi: 10.1021/acschemneuro.8b00437. (In my research of reported frequencies used for the Coronavirus SARS outbreak of a few years ago, a frequency of 152.2 Hz … Two dopamine concentration transients in the OT of a male rat associated with the introduction of a receptive female to the test chamber and subsequent contact. o The frequency range of alpha waves are 9 Hz to 13 Hz. We purposely used this design because the occurrence of dopamine transients was previously uncharacterized. Each scan took 9.3 msec to complete, and the electrode was held at −0.4 V between scans. The test animal was left undisturbed for an additional 190 sec between presentations; these periods were termed solitary episodes. Dopaminergic neurons periodically burst fire, and these bursts have been hypothesized to generate dopamine transients (Schultz, 1998). Voltammetric parameters, stimulation parameters, and data acquisition were controlled by a computer using LabVIEW computer instrumentation (National Instruments, Austin, TX) (Michael et al., 1999). Keywords: Similar results were seen when the data were pooled across brain regions and separated according to the type of conspecific rat presented (data not shown). S10B). GABAergic imbalance is normalized by dopamine D. Adenosine A1 receptor-mediated inhibition of dopamine release from rat striatal slices is modulated by D1 dopamine receptors. Conspecific episodes were defined as the 30 sec interaction time plus the 10 sec before and after presentation to account for any alerting stimuli (sounds, olfactory stimuli) associated with the introduction and removal of the conspecific. Seven of the males performed at least one intromission and one male ejaculated during the brief conspecific episodes. The x-axis displays time, with the end of intromission at 0 sec. Six recordings were made in the CP (rectangles), seven in the NA (circles) and four in the OT (triangles). For statistical analysis, the sum of the scores for each behavior in the 5 sec interval after the dopamine transient was compared with the sum of the scores for the 5 sec before (Fig.