Amygdala Neurons Differentially Encode Motivation and Reinforcement

“Numbers on the left indicate the anteroposterior coordinates caudal to bregma (Paxinos and Watson, 1998).”

“incentive and a reinforcer for different behavioral or environmental contingencies (Everitt and Robbins, 2005).”

“In contrast, a conditioned incentive is defined as a neutral stimulus that acquires motivating properties when associated with primary reinforcement, measured by behaviors such as conditioned approach (Berridge and Robinson, 2003).”

“For example, the BLA has robust reciprocal projections with the medial prefrontal cortex (mPFC) (Vertes, 2004).”

“…cocaine addicts produces intense drug craving (O’Brien et al., 1998), physiological arousal, including increased heart rate and skin conductance (Childress et al. 1988; Ehrman et al. 1992), and amygdala activation (Childress et al. 1999), all of which may lead to a relapse of drug-seeking behavior.”

“Because there is evidence that distinct populations of BLA neurons encode appetitive and aversive stimuli (Paton et al., 2006), it is likely that these neurons have different projections and that the function of the BLA lies in the absolute valence of the outcomes predicted by sensory stimuli, and…”

“In addition, the BLA sends inputs to the nucleus accumbens core (Kelley et al., 1982; Wright et al., 1996), and it has been reported that these connections are important for performing second-order conditioned responses (Setlow et al., 2002).”

“DOI:10.1523/JNEUROSCI.5281-06.2007 Copyright © 2007 Society for Neuroscience 0270-6474/07/273937-09$15.00/0 spond to sensory stimuli paired with positive or negative outcomes (Quirk et al., 1995; Uwano et al., 1995).”

“In agreement with a role for the BLA in conditioned reinforcement (Cador et al., 1989), the second population of cueresponsive neurons maintained their cue response while instrumental responding continued, perhaps reflecting the conditioned-reinforcing properties of the reward-paired cue that can motivate continued no…”

“This phenomenon is called cue-induced reinstatement and is an animal model for relapse to rewardseeking behavior (Epstein et al., 2006).”

“The nucleus accumbens has been suggested as a “final common pathway” for all types of reinstatement (cue-induced, drug-induced, stressinduced) (Kalivas and McFarland, 2003).”

“Lesion studies show that the BLA is important for outcome-specific incentive processes (Balleine et al., 2003; Corbit and Balleine, 2005).”

“…orbitofrontal cortex (OFC), which is reciprocally connected to the BLA (Kita and Kitai, 1990; Shi and Cassell, 1998), is thought to work in coordination with the BLA to use incentive information to guide behavior (Gallagher and Schoenbaum, 1999; Schoenbaum et al., 1999, 2003; Baxter et al., 2000).”

“…orbitofrontal cortex (OFC), which is reciprocally connected to the BLA (Kita and Kitai, 1990; Shi and Cassell, 1998), is thought to work in coordination with the BLA to use incentive information to guide behavior (Gallagher and Schoenbaum, 1999; Schoenbaum et al., 1999, 2003; Baxter et al., 2000).”

“The basolateral amygdala complex (BLA) is critically involved in the formation and expression of associations between sensory cues and rewarding or aversive stimuli (Davis, 1992; LeDoux, 1996; Gallagher, 2000; McGaugh, 2002).”

“It has been shown that lesions of either the BLA or OFC alter the neural encoding of information about expected outcomes and acquired value (Schoenbaum et al., 2003; Saddoris et al., 2005).”

“…cocaine addicts produces intense drug craving (O’Brien et al., 1998), physiological arousal, including increased heart rate and skin conductance (Childress et al. 1988; Ehrman et al. 1992), and amygdala activation (Childress et al. 1999), all of which may lead to a relapse of drug-seeking behavior.”

“BLA lesions attenuate responding to a cue associated with sexual reinforcement but do not alter sexual behavior itself (Everitt et al. 1989).”

“8) is reminiscent of studies done with extinction of cue-shock associations (Repa et al., 2001).”

“The mPFC is also important for cue-induced reinstatement of reward-seeking behavior (McLaughlin and See, 2003).”

“The basolateral amygdala complex (BLA) is critically involved in the formation and expression of associations between sensory cues and rewarding or aversive stimuli (Davis, 1992; LeDoux, 1996; Gallagher, 2000; McGaugh, 2002).”

“This evidence suggests that BLA function is specific to reinforcing properties of the reward-associated cue and does not affect reinforcing properties of the reward itself (Balleine et al., 2003).”

“The orbitofrontal cortex (OFC), which is reciprocally connected to the BLA (Kita and Kitai, 1990; Shi and Cassell, 1998), is thought to work in coordination with the BLA to use incentive information to guide behavior (Gallagher and Schoenbaum, 1999; Schoenbaum et al., 1999, 2003; Baxter et al.,…”

“Evidence suggests that the mPFC regulates the responsiveness of BLA neurons to odor cues previously associated with footshock (Rosenkranz et al., 2003).”

“…that the BLA is a site for the neural representation of reward-associated cues that induce reinstatement to reward-seeking behavior, consistent with studies showing that the BLA is critically involved in cue-induced reinstatement (Meil and See, 1997; Fuchs and See, 2002; Yun and Fields, 2003).”

“Importantly, it has been shown that varying with- drawal periods can affect extinction behavior and the degree to which cueinduced reinstatement is expressed (Grimm et al., 2002; Myers et al., 2006).”

“In addition, the BLA sends inputs to the nucleus accumbens core (Kelley et al., 1982; Wright et al., 1996), and it has been reported that these connections are important for performing second-order conditioned responses (Setlow et al., 2002).”

“…stimulus that acquires reinforcing properties when associated with primary reinforcement, and conditioned reinforcement can be measured by the ability of the cue to support instrumental responding in the absence of the primary reinforcer (Arroyo et al., 1998; Everitt and Robbins, 2000, 2005).”

“Studies have shown that pyramidal neurons and interneurons can be differentiated by both morphological and electrophysiological characteristics (Washburn and Moises, 1992; Rainnie et al., 1993).”

“…stimulus that acquires reinforcing properties when associated with primary reinforcement, and conditioned reinforcement can be measured by the ability of the cue to support instrumental responding in the absence of the primary reinforcer (Arroyo et al., 1998; Everitt and Robbins, 2000, 2005).”

“Rats readily lever press to self-administer primary reinforcers, such as sucrose, cocaine, or alcohol, and subsequently to obtain reward-paired cues in the absence of reward (Davis and Smith 1976; Meil and See 1997; Grimm et al. 2002; Nie and Janak, 2003).”

“…bursts per second, and percentage of total spikes that occur in bursts in the BLA neurons of the paired group as compared with the unpaired group (Table 2) suggest that the reward-paired cue may induce bursting of BLA neurons and are consistent with the study done by Laviolette et al. (2005).”

“It has been shown that lesions of either the BLA or OFC alter the neural encoding of information about expected outcomes and acquired value (Schoenbaum et al., 2003; Saddoris et al., 2005).”

“…that the BLA is a site for the neural representation of reward-associated cues that induce reinstatement to reward-seeking behavior, consistent with studies showing that the BLA is critically involved in cue-induced reinstatement (Meil and See, 1997; Fuchs and See, 2002; Yun and Fields, 2003).”

“Studies have shown that pyramidal neurons and interneurons can be differentiated by both morphological and electrophysiological characteristics (Washburn and Moises, 1992; Rainnie et al., 1993).”

“DOI:10.1523/JNEUROSCI.5281-06.2007 Copyright © 2007 Society for Neuroscience 0270-6474/07/273937-09$15.00/0 spond to sensory stimuli paired with positive or negative outcomes (Quirk et al., 1995; Uwano et al., 1995).”

“Electrophysiological characterization of neuronal response types Pyramidal projection neurons compose 95% of the neurons in the BLA, the remainder being interneurons (McDonald 1982, 1984).”

“In addition, the BLA sends inputs to the nucleus accumbens core (Kelley et al., 1982; Wright et al., 1996), and it has been reported that these connections are important for performing second-order conditioned responses (Setlow et al., 2002).”

“Rats readily lever press to self-administer primary reinforcers, such as sucrose, cocaine, or alcohol, and subsequently to obtain reward-paired cues in the absence of reward (Davis and Smith 1976; Meil and See 1997; Grimm et al. 2002; Nie and Janak, 2003).”

“Rats readily lever press to self-administer primary reinforcers, such as sucrose, cocaine, or alcohol, and subsequently to obtain reward-paired cues in the absence of reward (Davis and Smith 1976; Meil and See 1997; Grimm et al. 2002; Nie and Janak, 2003).”

“…that the BLA is a site for the neural representation of reward-associated cues that induce reinstatement to reward-seeking behavior, consistent with studies showing that the BLA is critically involved in cue-induced reinstatement (Meil and See, 1997; Fuchs and See, 2002; Yun and Fields, 2003).”

“…orbitofrontal cortex (OFC), which is reciprocally connected to the BLA (Kita and Kitai, 1990; Shi and Cassell, 1998), is thought to work in coordination with the BLA to use incentive information to guide behavior (Gallagher and Schoenbaum, 1999; Schoenbaum et al., 1999, 2003; Baxter et al., 2000).”

“from the present meta-analysis provide strong evidence that the amygdala is equally sensitive to rewarding stimuli, as confirmed by a wealth of animal studies (Sugase-Miyamoto and Richmond, 2005; Tye and Janak, 2007; Bermudez et al., 2012).”