Positive Incentive Motivation Research Articles

Repeated Cocaine Exposure Attenuates the Desire to Actively Avoid: A Novel Active Avoidance Runway Task.

Drug addiction is a disorder in which drug seeking persists despite aversive consequences. While it is well documented in animal models of drug sensitization that repeated drug exposure enhances positive incentive motivation for drug and natural reinforcers, its effect on negative incentive motivation, defined here as the motivation to avoid a cued aversive outcome, remains an open question. In the present study, we designed a novel active avoidance (AA) runway paradigm to assess the effects of repeated cocaine exposure on the motivation to avoid an aversive outcome. Cocaine and saline pre-exposed rats were first trained to perform a conditioned AA lever press response to prevent the occurrence of foot shock administrations. The rats were subsequently tested in a runway apparatus, wherein they were required to traverse the length of a straight alley maze to reach the lever and emit a conditioned AA response. Run times were measured as an indication of negative incentive motivation. Cocaine pre-exposed rats demonstrated longer latencies to emit the conditioned AA response but showed no differences in latency to initiate runway behavior, nor in their acquisition of the AA response compared to the saline pre-exposed controls. Subsequent testing in an elevated plus maze revealed no differences in the expression of anxiety in cocaine pre-exposed rats compared to saline pre-exposed controls. Our results indicate that prior repeated cocaine exposure attenuated cued negative incentive motivation, which suggests that drug addiction may be attributable to a decrease in motivation to avoid aversive consequences associated with drug use.

Distinct Roles of Opioid and Dopamine Systems in Lateral Hypothalamic Intracranial Self-Stimulation.

Background:Opioid and dopamine systems play crucial roles in reward. Similarities and differences in the neural mechanisms of reward that are mediated by these 2 systems have remained largely unknown. Thus, in the present study, we investigated the differences in reward function in both µ-opioid receptor knockout mice and dopamine transporter knockout mice, important molecules in the opioid and dopamine systems.Methods:Mice were implanted with electrodes into the right lateral hypothalamus (l hour). Mice were then trained to put their muzzle into the hole in the head-dipping chamber for intracranial electrical stimulation, and the influences of gene knockout were assessed.Results:Significant differences are observed between opioid and dopamine systems in reward function. µ-Opioid receptor knockout mice exhibited enhanced intracranial electrical stimulation, which induced dopamine release. They also exhibited greater motility under conditions of “despair” in both the tail suspension test and water wheel test. In contrast, dopamine transporter knockout mice maintained intracranial electrical stimulation responding even when more active efforts were required to obtain the reward.Conclusions:The absence of µ-opioid receptor or dopamine transporter did not lead to the absence of intracranial electrical stimulation responsiveness but rather differentially altered it. The present results in µ-opioid receptor knockout mice are consistent with the suppressive involvement of µ-opioid receptors in both positive incentive motivation associated with intracranial electrical stimulation and negative incentive motivation associated with depressive states. In contrast, the results in dopamine transporter knockout mice are consistent with the involvement of dopamine transporters in positive incentive motivation, especially its persistence. Differences in intracranial electrical stimulation in µ-opioid receptor and dopamine transporter knockout mice underscore the multidimensional nature of reward.

Repeated cocaine exposure induces sensitization of ultrasonic vocalization in rats

Ultrasonic vocalization at 55 kHz (55 kHz-USVs) by rodents has been proposed to be a behavioral manifestation of affectively positive incentive motivation. To examine the extent to which 55 kHz-USV emissions correlate with cocaine-induced locomotor activity, we measured cocaine-induced 55 kHz-USVs and their relationship to cocaine-induced locomotor sensitization in rats. We demonstrate that similar to locomotor responses, 55 kHz-USVs are also sensitized by exposure to cocaine. Furthermore, we show that the magnitude of cocaine-induced 55 kHz-USV sensitization is positively correlated with that of locomotor sensitization. Moreover, we demonstrate that rats selectively bred for high rates of 55 kHz-USVs exhibit higher levels of cocaine-induced 55 kHz-USV sensitization than animals selectively bred for low levels of 55 kHz USVs. These results suggest that the neural circuits underlying 55 kHz-USV, which may directly reflect affective experience/motivation, can be sensitized by cocaine in a way that resembles locomotor sensitization.

Incentive motivation is associated with striatal dopamine asymmetry

Dopamine plays an important role in modulating incentive motivation, expressed behaviorally as approach behavior. EEG studies report association between approach behavior and asymmetric pattern of activation in anterior cortical regions (as measured by the inverse of EEG alpha power). Therefore, individual differences in incentive motivation may reflect asymmetries in dopaminergic systems. We examined this hypothesis by studying the relationship between self-reported degree of incentive motivation, and asymmetry of D2 receptor availability in healthy volunteers. Nineteen healthy participants were studied with positron emission tomography (PET) and [11C]raclopride to assess the availability of dopamine D2 receptors in left and right striatum. Incentive motivation was assessed by the Achievement scale of the Multidimensional Personality Questionnaire. The Achievement score was negatively correlated with the Asymmetry Index ([R − L]/[R + L]) of D2 receptor availability ( r = −.721, p = .001), suggesting that greater positive incentive motivation is associated with higher receptor availability in the left relative to the right hemisphere.

Personality Correlates of Prepulse Inhibition of the Startle Reflex at Three Lead Intervals

Abstract The acoustic startle reflex (ASR) is modulated by a number of experimental factors, the most important of which in the field of psychopathology is weak prestimulation: The ASR is reliably reduced if preceded briefly by a weaker stimulus (i. e., the prepulse), an effect known as prepulse inhibition (PPI). PPI is thought to reflect centrally-mediated sensorimotor gating of stimuli, preventing cognitive overload and behavioural confusion. PPI is impaired in a variety of psychiatric disorders, notably schizophrenia, as well as in individuals who score high on psychometric measures of psychosis proneness. Two experiments examined the association of personality (trait emotionality) and PPI at three prepulse-to-pulse intervals (30, 60 and 120 ms). Consistent with previous reports, findings from both experiments showed highly significant PPI (defined as percentage reduction in the amplitude of the ASR), which increased with prepulse-to-pulse interval (30 < 60 < 120 ms). A novel finding was that, in both experiments 1 (N = 36) and 2 (N = 63), the trait of neuroticism was negatively correlated with PPI; in addition, a measure of positive incentive motivation (i. e., Behavioural Activation System, Drive subscale; BAS-Drive) was also negatively correlated with PPI. These trait emotionality associations were independent of gender. Possible causal explanations of these personality associations are outlined. It is concluded that, in order to clarify the aetiological role of sensorimotor gating in psychopathological conditions (e. g., schizophrenia, often entailing emotional activation), trait emotionality variance should be routinely examined in future PPI studies.

The effects of oral selegiline hydrochloride on learning and training in the dog: a psychobiological interpretation

1. Twenty two healthy, non-problem dogs were assessed for their acquisition of three different learning tasks on consecutive days and on the extinction of the response in the third. In Task 1, dogs were trained to walk in a circle on command. In Task 2, dogs were trained to retreat and sit on a mat. In Task 3, dogs were assessed for the acquisition and extinction of an operant response (pawing a panel). 2. Dogs were orally administered a placebo or selegiline hydrochloride at a dose of 0.5mg/kg for a period of three weeks prior to testing and during the test period. 3. Dog's treated with selegiline tended to perform better at tasks which were clearly lured with a motivationally significant cue, performing a first correct response sooner and requiring fewer reinforcements to reach the success criterion. They were also significantly more likely to walk over a novel object placed on the floor of the test arena. In the absence of a significant lure, the selegiline treated dogs took significantly longer to reach the required performance criterion for the operant task. These dogs also extinguished their response more rapidly than the control group 4. In the third task, selegiline treated dogs were significantly less likely to look away and throughout all tasks these dogs tended to be less distracted than the placebo group. 5. These findings and other reports associated with the effects of selegiline on learning may be explained by reference to the effects of selegiline on dopaminergic structures associated with positive incentive motivation.

Film-induced incentive motivation and positive activation in relation to agentic and affiliative components of extraversion

Abstract Recently we argued that a core process underlying the trait of extraversion is positive incentive motivation, an association that particularly characterizes the agentic as opposed to the affiliative component of extraversion (Depue & Collins, Behavioral and Brain Sciences, 22 , 1–79, 1999). Due to a paucity of methods that specifically induce incentive motivation–positive activation (as opposed to solely amusement and pleasantness), this study developed dynamic film material that activates such subjective experience. Moreover, the films represent three levels of magnitude of induced incentive motivation–positive activation, ranging from minimal to moderate to strong. Therefore, individual differences in film-induced positive activation could be expressed as a stimulus intensity–response function via the slope of positive activation ratings across the range of incentive magnitudes. Film-induced reactivity in positive activation, as opposed to pre-film basal positive activation, was preferentially related to extraversion. Moreover, the slope of post-film positive activation across films, reflecting a stimulus intensity–response function, was more robustly related to overall estimates of extraversion ( r =0.34, p r =0.32, p r =0.18, p =0.09) component of extraversion. The findings suggest that a unitary concept of extraversion may be incorrect, and that further research is necessary to characterize the nature of agentic and affiliative components of the trait. The film method reported herein provides one means of investigating the incentive motivation–positive activation nature of extraversion.

But the schizophrenia connection . . .

As well as data indicating relationships (emphasised in the target article) (1) between dopaminergic transmission in the nucleus accumbens and positive incentive motivation, and (2) between dopaminergic transmission and extraversion, other data (not accounted for by the hypotheses developed in the target article) indicate relationships (3) between accumbens dopaminergic transmission and cognitive, especially perceptual, processes that are disrupted in schizophrenia, and (4) between dopaminergic transmission and psychoticism. The tension between relationships 1 + 2 and 3 + 4 is discussed and a tentative resolution proposed.

Functions of the dopaminergic innervation of the nucleus accumbens

Two different current views hold that the mesolimbic dopaminergic projection to the nucleus accumbens mediates (1) the behavioral effects of reward or positive incentive motivation and (2) the cognitive functions that go awry in acute schizophrenia. These two views are difficult to integrate with each other. The former view fits better with the established role that the nucleus accumbens plays in the motor programming circuitry of the basal ganglia; but it fits poorly with evidence that dopamine release is provoked in the nucleus accumbens not only by rewarding, but also by aversive, stimuli. We review evidence, especially from experiments using the prepulse and latent inhibition paradigms, consistent with a role for the mesolimbic dopaminergic pathway in the cognitive dysfunctions of schizophrenia. We also propose a new model for the functions of this pathway which draws on recent evidence that the nucleus accumbens has outputs to perceptual as well as motor systems. The model is able in principle to account for the data sets that support both major current views of the functions of the mesolimbic dopaminergic system. It has not yet received support, however, from direct experimental tests.

Incentive motivation: Just extraversion?

Is a generalized positive incentive motivation a construct appropriate to the human level of behavior or would sensation or novelty seeking be a more appropriate one? Is positive incentive motivation, or susceptibility to signals of reward, a mechanism related only to extraversion traits including sociability, activation, social potency, and positive affect? Research shows that susceptibility to reward is related to impulsive sensation seeking and aggression as well as sociability and an aroused type of positive affect. Comparative and indirect human correlates suggest an involvement of dopaminergic reactivity in sensation seeking and sociability.

Does extraversion predict positive incentive motivation?

I focus on a number of issues arising from Depue & Collins's target article that require further consideration: (1) data that fail to confirm extraversion effects in positive incentive experiments; (2) the role of personality factors, other than extraversion, in dopamine agonism on positive mood states; (3) the role of extraversion in nonspecific arousal, indicating that extraversion may not be an homogeneous trait; and (4) the problem of identifying neurobiologically important traits from existing structural models of personality. I applaud the heuristic value of the model presented and suggest ways in which aspects of the model may be used to identify the personality traits associated with positive incentive motivation.

Temperament and Response Processing: Facilitatory and Inhibitory Consequences of Positive and Negative Motivational States

Individual differences in response facilitation and inhibition were assessed through a modified go/no go task presented in alternating positive (where points could be gained) and negative (where points could be lost) incentive blocks. Neurotic extraverts showed enhanced facilitation on positive blocks following positive feedback. Neurotic introverts and individuals high in STAI trait anxiety showed enhanced inhibition on negative blocks. Individuals high in I 7 impulsiveness showed generally low inhibition. These results support models proposing that positive incentive motivation and its facilitatory response consequences peak in neurotic extraverts, whereas negative incentive motivation and its inhibitory effects peak in neurotic introverts. However, neurotic introverts were also relatively fast in responding following negative feedback, which confirms recent reports of "anxious impulsivity."

A neural theory of punishment and avoidance, II: quantitative theory

Quantitative neural networks are derived from psychological postulates about punishment and avoidance. The classical notion that derive reduction is reinforcing is replaced by a precise physiological alternative akin to Miller's “Go” mechanism and Estes's “amplifier” elements. Cell clusters A + f and A - f are introduced which supply negative and positive incentive motivation, respectively, for classical conditioning sc sensory-motor acts. The A + f cells are persistently turned on by shock (on-cells). The A - f cells are transiently turned on by shock termination (scf-cells). The rebound from A + f cell activation to A - f cell activation replaces drive reduction in the case sc shock. Classical conditioning from sensory cells L to the pattern sc activity playing on arousal cells A f = ( A + f , A - f ) can occur. Sufficiently positive net feedback from A f to L can release sampling, and subsequent learning, by prescribed cells in L sc motor output controls. Once sampled, these controls can be reactivated by L on recall trials. This concept avoids some difficulties sc two-factor theories sc punishment and avoidance. Recent psychophysiological data and concepts are analyzed in terms sc network analogs, and some predictions are made. The rebound from A + f cell activation to A - f cell activation at shock termination is interpreted to be a consequence sc different rates sc transmitter accumulation — depletion in the parallel neural channels associated with A + f and A - f . This interpretation culminates in an analogy with adrenergic and cholinergic interactions at lateral and ventromedial hypothalamic sites, dependent on phasic sensory input and tonic reticular formation input. Mechanisms are suggested for such phenomena as: the greater rewarding effect sc reducing J units sc shock to J/2 units than sc reducing J/2 units to 0 units; a relationship between the rewarding effect sc reducing J units sc shock to J/2 units and the possibility sc releasing a conditioned avoidance response in the presence sc fearful cues; two kinds sc depressed emotional affect, one due to overarousal, that can also be associated with massive associational confusions and poor paying attention, and one due to underarousal, that can also be associated with overreactive fear and relief responses; persistent nonspecific fear that biases interpretation sc specific cues, and can “resist” new learning or “repress” old learning; different effects sc gradual and abrupt shock on response suppression; response generalization from one shock level to another; reduction sc pain in the presence sc loud noise (analgesia); influences sc drugs, such as carbachol, atropine, and scopolamine on conditioned emotional and avoidance responses, and on self-stimulation via implanted hypothalamic electrodes; sensory-drive heterarchy that allows changes in situational cues to release responses compatible with any sc several nonprepotent drives; feedback inhibition sc adrenergic transmitter production; potentiation sc adrenergic production by presynaptic spiking, and by postsynaptic spiking via a feedback loop that controls higher-order instrumental conditioning; learning at cholinergic synapses.

A neural theory of punishment and avoidance, I: Qualitative theory

Neural networks are derived from psychological postulates about punishment and avoidance. The classical notion that drive reduction is reinforcing is replaced by a precise physiological alternative akin to Miller's ’Go” mechanism and Estes's ’amplifier” elements. Cell clusters A + ƒ and A − ƒ are introduced which supply negative and positive incentive motivation, respectively, for classical conditioning of sensory-motor acts. The A + ƒ cells are persistently turned on by shock (on-cells). The A + ƒ cells are transiently turned on by shock termination (off-cells). The rebound from A + ƒ cell activation to A − ƒ cell activation replaces drive reduction in the case of shock. Classical conditioning from sensory cells L to the pattern of activity playing on arousal cells A ƒ=( A + ƒ, A − ƒ) can occur. Sufficiently positive net feedback from A ƒ to L can release sampling, and subsequent learning, by prescribed cells in L of motor output controls. Once sampled, these controls can be reactivated by L on recall trials. This concept avoids some difficulties of two-factor theories of punishment and avoidance. Estes' stimulus sampling theory of punishment is neurally interpreted. Recent psychophysiological data and concepts are qualitatively analyzed in terms of network analogs. These concepts include aspects of relaxation, or elicitation, theory, which claims that an unconditioned response of relief precedes reinforcement; the concept of ’effective reinforcement,” which notes that shock offset and fear of situational cues can influence reward in opposite ways, as is illustrated by one-way and two-way avoidance tasks; classical and instrumental properties of a CS+ paired with shock, a CS— paired with no-shock, and feedback stimuli contingent on the avoidance response, including transfer of their effects from classical to instrumental conditioning experiments; autonomically nonchalant asymptotic avoidance performance originally motivated by fear; forced extinction of the conditioned avoidance response (CAR) without fear extinction; response suppression without an avoidance response; relief without an avoidance response; opposite effects of contingent and noncontingent punishment on fear and suppression of consummatory responding; punishment hypothesis of avoidance learning, describing rewarding effects of terminating proprioceptive cues that correspond to nonavoidance responses; response (or no-response) generalization from one shock level to a different level; rewarding effect of response-contingent reduction in frequency of shock.