Barker, DJ (2018). Ultrasonic Vocalizations as an Index of Positive Emotional State. Handbook of Behavioral Neuroscience25, 253-260.

Simmons, SJ, Barker, DJ, & West, MO (2018). Ultrasonic Vocalizations Capture Opposing Affective States During Drug Self-Administration: Revisiting the Opponent-Process Model of Addiction. Handbook of Behavioral Neuroscience25, 389-399.

Lo, M, Wang S, Singh S, Damodaran VB, Coffey K, Barker DJ, Saste K, Kals, K, Kaplan HM, Kohn J, Shreiber DI, Zahn JD. (2018) Evaluating the in vivo glial response to miniaturized parylene cortical probes coated with an ultra-fast degrading polymer to aid insertion. Journal of neural engineering15(3), 036002. [Download]

Simmons SJ, Gregg RA, Tran FH, Mo L, vonWeltin E, Barker DJ, Gentile TA, Watterson LR, Rawls SM, Muschamp JW. (2018) Comparison of the rewarding and reinforcing effects of ‘bath salt’ 3,4-methylenedioxypyrovalerone (MDPV) and cocaine using ultrasonic vocalizations in rats. Addiction Biology, doi: 10.1111/adb.12479. [Download]

Gentile TA, Simmons SJ, Barker DJ, Shaw JK, España RA, Muschamp JW (2018). Suvorexant, an orexin/hypocretin receptor antagonist, attenuates motivational and hedonic properties of cocaine. Addiction biology23(1), 247-255. [Download]


Barker DJ, Root DH, Zhang S, Miranda-Barrientos J, Wang HL, Morales M. (2017) Lateral preoptic control of the lateral habenula through convergent glutamate and GABA transmission. Cell reports, 21(7), 1757-1769. [Download]

Barker, DJ, & Johnson, AM (2017). Automated acoustic analysis of 50-kHz ultrasonic vocalizations using template matching and contour analysis. The Journal of the Acoustical Society of America, 141(3), EL281-EL286. [Download]

Campbell EJ, Barker DJ, Nasser HM, Kaganovsky K, Dayas CV, Marchant NJ. (2017)  Cue-induced food seeking after punishment is associated with increased Fos expression in the lateral hypothalamus, basolateral and medial amygdala. Behav. Neurosci, doi: 10.1037/bne0000185. [Download]


Barker DJ, Root DH, Zhang S, Morales M. (2016). Multiplexed neurochemical signaling by neurons of the ventral tegmental area. pii: S0891-0618(16)00002-8. doi: 10.1016/j.jchemneu.2015.12.016. [Download]
*2016 Neuroscience highly-cited collection

Root DH, Wang HL, Liu B, Barker DJ, Silva AC, Magloczky Z, Morales M. (2016) Dopamine neurons in the midbrain of nonhuman primates and humans are intermingled with glutamatergic and dual glutamatergic-dopaminergic neurons. Scientific Reports, Article 30615, doi:10.1038/srep30615. [Download]

Qi J, Zhang S ,Wang HL, Barker DJ, Miranda-Barrientos J, Morales M. (2016) VTA glutamatergic inputs to nucleus accumbens drive aversion by acting on GABAergic interneurons. Nature Neuroscience, 19(5): 725-33, doi: 10.1038/nn.4281. [Download]


Barker DJ, Simmons SJ, West MO (2015). Ultrasonic vocalizations as a measure of affect in preclinical models of drug abuse: A review of current findings. Current Neuropharmacology, 13(2):193-210. [Download]

Coffey K*, Barker DJ*, Gayliard N, Kulik J, Pawlak AP, West MO (2015). Electrophysiological evidence of alterations to the nucleus accumbens and dorsolateral striatum during chronic cocaine self-administration. Eur J. Neurosci, 41(12):1538-52. doi: 10.1111/ejn.12904. [Download] * Co-First Authors.

Barker DJ, Striano BM, Pawlak AP, Kim O, Root DH, Fabbricatore AT, West MO. (2015) Sensitivity to self-administered cocaine within the lateral preoptic-rostral lateral hypothalamic continuum. Brain Struct Funct, 220(3):1841-54. doi: 10.1007/s00429-014-0736-6. [Download]

Ma S, Barker DJ. (2015). Predicting spiking activities in DLS neurons with linear-nonlinear-poisson model. JMLR: Workshop and Conference Proceedings, 11:85-92. [Download]


Barker DJ, Herrera C, West MO. (2014) Automated detection of 50-kHz ultrasonic vocalizations using template matching in XBAT. J. Neurosci Methods, 236:68-75 doi: 10.1016/j.jneumeth.2014.08.007. [Download]

Barker DJ, Bercovicz D, Servilio LC, Simmons SJ, Ma A, Root DH, Pawlak AP, West MO (2014). Rat Ultrasonic Vocalizations Demonstrate that the Motivation to Contextually Reinstate Drug-Seeking Behavior does not Necessarily Involve a Hedonic Response. Addiction biology, 19(5), 781-790 doi: 10.1111/adb.12044. [Download]

Striano, BM, Barker DJ, Pawlak AP, Root DH, Coffey KR, Fabbricatore AT, West MO.  (2014) Olfactory Tubercle neurons exhibit slow-phasic firing patterns during cocaine self-administration. Synapse, 68 (7): 321-3. [Download]

Barker DJ, Simmons SJ, Servilio LC,  Bercovicz D, Root DH, Ma S, West MO (2014). Ultrasonic vocalizations: evidence for an affective opponent process during cocaine self-administration. Psychopharmacology,231(5):909-918. [Download]

Barker DJ. (2014). Making WAAVES in the vocalization community, but how big is the splash? J. Neuroscience Methods, 221:-228-229. [Download]

Barker DJ, Coffey KR, Ma S, Root DH, West MO. (2014). A procedure for implanting  organized arrays of microwires for single-unit recordings in the awake behaving animal. J Vis Exp, (84):e51004. [Download]


Coffey KR, Barker DJ, Ma S, West MO. (2013). Building an open-source robotic stereotaxic instrument. J Vis. Exp, (80), e51006, doi:10.3791/51006. [Download]

Ma S, Cho J, Root DH, Barker DJ, Pawlak AP, West MO. (2013) Amphetamine’s Dose-   dependent effects on dorsolateral striatum sensorimotor neuron firing. Behav. Brain Res, 244: 152-61[Download]

Coffey KR, Barker DJ, Ma S, Root DH, Martinez L, Horvitz JC, West MO (2013) Effect of varying reinforcement probability on Pavlovian approach behavior and ultrasonic vocalizations in rats. Behav. Brain Res, 237: 256-262. [Download]

Root DH, Ma S, Barker DJ, Megehee L, Striano BM, Ralston CM, Fabbricatore AT, West MO (2013). Differential roles of ventral pallidum subregions during cocaine self-administration behaviors. J Comp. Neurol 521(3): 558-88. [Download]


Root DH, Fabricatore AT, Pawlak AP, Barker DJ, Ma S, West MO (2012). Slow Phasic and tonic activity of ventral pallidal neurons during cocaine self-administration. Synapse, 66(2):106-127. [Download]


Root DH, Barker DJ, Ma S, Coffey KR, Fabbricatore AT, West MO (2011). Evidence for learned skill during cocaine self-administration in rats. Psychopharmacology 217(1):91-100. [Download]


Barker DJ, Root DH, Ma S, Jha S, Megehee L, Pawlak AP, West MO. (2010). Dose dependent differences in short ultrasonic vocalizations emitted by rats during cocaine self-administration. Psychopharmacology 211(4): 435-442. [Download]

Barker DJ, Sanabria F, Lasswell A, Thrailkill EA, Pawlak AP, Killeen PR. (2010). Brief light as a practical aversive stimulus for the albino rat. Behav. Brain Res 214(2): 402-408. [Download]

Root DH, Fabbricatore AT, Ma S, Barker DJ, West MO. (2010) Rapid phasic activity of ventral pallidal neurons during cocaine self-administration. Synapse 64(9): 704-713. [Download]


Tang CC,  Root DH,  Duke DC, Zhu Y, Teixeria K, Ma S, Barker DJ, West MO. (2009). Decreasing firing of striatal neurons related to licking during acquisition and overtraining of a licking task. J. Neurosci 29(44): 13952-13961. [Download]

Root DH, Fabbricatore AT, Barker DJ, Ma S, Pawlak AP, West MO. (2009). Evidence for habitual and goal directed behavior following devaluation of cocaine: a multifaceted interpretation of relapse. PloS One 4: e7170. [Download]

Root DH, Barker DJ, Ma S. (2009). Duality of salience in dopamine neurons. PNAS 106(31): E84. [Download]