Direct Activation of the Ventral Striatum in Anticipation of Aversive Stimuli

Abstract

The brain "reward" system, centered on the limbic ventral striatum, plays a critical role in the response to pleasure and pain. The ventral striatum is activated in animal and human studies during anticipation of appetitive/pleasurable events, but its role in aversive/painful events is less clear. Here we present data from three human fMRI studies based on aversive conditioning using unpleasant cutaneous electrical stimulation and show that the ventral striatum is reliably activated. This activation is observed during anticipation and is not a consequence of relief after the aversive event. Further, the ventral striatum is activated in anticipation regardless of whether there is an opportunity to avoid the aversive stimulus or not. Our data suggest that the ventral striatum, a crucial element of the brain "reward" system, is directly activated in anticipation of aversive stimuli.

The Formation of Abnormal Associations in Schizophrenia: Neural and Behavioral Evidence

“…Two-sample t-tests were used to test for differences in brain activations for the CS + vs the CSÀ between the patients with schizophrenia and the healthy controls. Searching a small volume centered at previously reported coordinates (Jensen et al, 2003), an activation in the ventral striatum (peak at coordinate À6, 12, 3; Z ¼ 3.08; po0.05) for the healthy controls as compared to the patients were obtained (Figure 3). An examination of the b values (Figure 3) showed that this difference was driven by a much larger response to the CSÀ among the patients while both patients and controls had similar responses to CS + .…”

“…The ventral striatum plays a central role in reward processing and it has been suggested that activations of the ventral striatum normally mediate the incentive or motivational salience of environmental stimuli (Jensen et al, 2003(Jensen et al, , 2007Zink et al, 2003Zink et al, , 2004Zink et al, , 2006. The stronger responses to the neutral stimulus among patients may reflect an aberrant attribution of motivational salience to neutral stimuli (Kapur, 2003).…”

“…For the healthy controls, we also made a within-group analysis to establish that the contrast [CS + vs CSÀ] yielded activations in the ventral striatum similar to previous studies (Jensen et al, 2003). The data were thresholded at FDRo0.05 except for the CS + vs CSÀ comparisons where small volume correction for regions of interest (ventral striatum) were used based on coordinates from a previous study (Jensen et al, 2003). We used spheres with a radius of 9 mm centered on MNI coordinates À8, 10, À2 for the left ventral striatum and 12, 6, À4 for the right ventral striatum.…”

“…The between group random effects models investigated the effects of CS + , CSÀ and CS + vs CSÀ respectively. For the healthy controls, we also made a within-group analysis to establish that the contrast [CS + vs CSÀ] yielded activations in the ventral striatum similar to previous studies (Jensen et al, 2003). The data were thresholded at FDRo0.05 except for the CS + vs CSÀ comparisons where small volume correction for regions of interest (ventral striatum) were used based on coordinates from a previous study (Jensen et al, 2003).…”

Valence and salience contribute to nucleus accumbens activation

“…Cue salience might increase with absolute incentive magnitude (good or bad), incentive uncertainty, or the contingency of the response (i.e., how important an organism's response is to the outcome). The salience account references evidence that NAcc activation increases with behavioral demands or interference (Tricomi et al, 2004;Zink et al, 2004;Zink et al, 2006), in response to novel nonrewarded events (Zink et al, 2003), or in anticipation of painful stimulation (Berridge and Robinson, 1998;Jensen et al, 2003). At least two studies have reported NAcc activation correlated with salience prediction error models of conditioning for painful stimuli that included decreases during unpredicted avoidance of painful stimuli (Jensen et al, 2007;Seymour et al, 2004).…”