Brainstem Correlates of Defensive States in Humans

Baas, Johanna M.P.; Milstein, Jean A.; Donlevy, Meghan; Grillon, Christian

doi:10.1016/j.biopsych.2005.09.009

Cited by 71 publications

(59 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, the startle reflex-a somatic marker of defensive motivation (Lang, Bradley, & Cuthbert, 1992)-is enhanced during the anticipation of unpredictable as compared to predictable shocks (Bradford, Shapiro, & Curtin, 2013;Grillon, Baas, Lissek, Smith, & Milstein, 2004;Hefner & Curtin, 2012;Shankman, Robison-Andrew, Nelson, Altman, & Campbell, 2011), and fMRI research involving similar contrasts has indicated sustained hyperactivity in attentional networks (Carlsson et al, 2006;Hasler et al, 2007). Consistently, unpredictable threat of shock facilitates early perceptual and attentional processing, even with uncertainty-independent neutral stimuli (Baas, Milstein, Donlevy, & Grillon, 2006;Cornwell et al, 2007;Nelson, Hajcak, & Shankman, 2015;Shackman, Maxwell, McMenamin, Greischar, & Davidson, 2011). Thus, uncertainty-related defensive motivation is strongly tied to enhanced attentive stimulus processing, possibly aiming at threat elimination.…”

mentioning

confidence: 70%

“…This elucidates important differences between the attentional dynamics to uncertainly cued targets, which we examined here, and stimuli encountered under conditions of unpredictable threat but otherwise noninformative about and unrelated to uncertainty. The latter stimuli tend to elicit an attentional response characterized by increased early and decreased later resource allocation (Baas et al, 2006;Cornwell et al, 2007;Nelson et al, 2015;Shackman et al, 2011), which has been interpreted as rapid stimulus discrimination-facilitating the resolution of uncertainty-but subsequent disengagement after categorizing a stimulus as irrelevant to impending threat. Contrarily, as we presently observed, the uncertainty-related LPP does not normalize during the presentation of uncertainly cued targets, reflecting a sustained attentional response that is unlikely to facilitate the resolution of uncertainty through valence discrimination.…”

Section: Discussionmentioning

confidence: 99%

“…Defensive emotional responding, as indicated by fMRI and autonomic measures (Grupe & Nitschke, 2011;Sarinopoulos et al, 2010;Williams et al, 2015), implies that uncertainly cued targets elicit sustained elaboration (Amrhein, Mühlberger, Pauli, & Wiedemann, 2004;Cuthbert, Schupp, Bradley, Birbaumer, & Lang, 2000;Liu, Huang, McGinnis-Deweese, Keil, & Ding, 2012), contrasting with the aforementioned early responses to uncertainty-independent neutral stimuli (Baas et al, 2006;Cornwell et al, 2007;Nelson et al, 2015;Shackman et al, 2011). Therefore, we utilized event-related potentials (ERPs), exploiting their excellent temporal resolution and sensitivity to attentional processes, to investigate the uncertainty-related dynamics in attentional allocation and sustained stimulus elaboration in a cued-picture paradigm (Grupe & Nitschke, 2011;Sarinopoulos et al, 2010).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Uncertainty is associated with increased selective attention and sustained stimulus processing

Dieterich

Endraß

Kathmann

2016

Cogn Affect Behav Neurosci

View full text Add to dashboard Cite

Uncertainty about future threat has been found to be associated with an overestimation of threat probability and is hypothesized to elicit additional allocation of attention. We used event-related potentials to examine uncertainty-related dynamics in attentional allocation, exploiting brain potentials' high temporal resolution and sensitivity to attention. Thirty participants performed a picture-viewing task in which cues indicated the subsequent picture valence. A certain-neutral and a certain-aversive cue accurately predicted subsequent picture valence, whereas an uncertain cue did not. Participants overestimated the effective frequency of aversive pictures following the uncertain cue, both during and after the task, signifying expectancy and covariation biases, and they tended to express lower subjective valences for aversive pictures presented after the uncertain cue. Pictures elicited increased P2 and LPP amplitudes when their valence could not be predicted from the cue. For the LPP, this effect was more pronounced in response to neutral pictures. Uncertainty appears to enhance the engagement of early phasic and sustained attention for uncertainly cued targets. Thus, defensive motivation related to uncertainty about future threat elicits specific attentional dynamics implicating prioritization at various processing stages, especially for nonthreatening stimuli that tend to violate expectations.

show abstract

mentioning

confidence: 70%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Uncertainty is associated with increased selective attention and sustained stimulus processing

Dieterich

Endraß

Kathmann

2016

Cogn Affect Behav Neurosci

View full text Add to dashboard Cite

show abstract

“…This same relationship was true for right auditory structures (BA 41) prior to 150 ms post-stimulus onset, suggesting that higher anxiety levels were associated with earlier engagement of right auditory processes under threat. A modulation of early auditory processes by threat of shock is not unprecedented as auditory brainstem potentials have been shown to be potentiated by a very similar manipulation of anticipatory anxiety (Baas et al, 2006). In the current study, participants reported, on average, a medium anxiety level to threat of shock.…”

Section: Discussionmentioning

confidence: 99%

Neural responses to auditory stimulus deviance under threat of electric shock revealed by spatially-filtered magnetoencephalography

et al. 2007

Self Cite

View full text Add to dashboard Cite

Stimulus novelty or deviance may be especially salient in anxiety-related states due to sensitization to environmental change, a key symptom of anxiety disorders such as posttraumatic stress disorder (PTSD). We aimed to identify human brain regions that show potentiated responses to stimulus deviance during anticipatory anxiety. Twenty participants (14 men) were presented a passive oddball auditory task in which they were exposed to uniform auditory stimulation of tones with occasional deviations in tone frequency, a procedure that elicits the mismatch negativity (MMN) and its magnetic counterpart (MMNm). These stimuli were presented during threat periods when participants anticipated unpleasant electric shocks, and safe periods when no shocks were anticipated. Neuromagnetic data were collected with a 275-channel whole-head MEG system and event-related beamformer analyses were conducted to estimate source power across the brain in response to stimulus deviance. Source analyses revealed greater right auditory and inferior parietal activity to stimulus deviance under threat relative to safe conditions, consistent with locations of MMN and MMNm sources identified in other studies. Structures related to evaluation of threat, left amygdala and right insula, also showed increased activity to stimulus deviance under threat. As anxiety level increased across participants, right and left auditory cortical as well as right amygdala activity increased to stimulus deviance. These findings fit with evidence of a potentiated MMN in PTSD relative to healthy controls, and warrant closer evaluation of how these structures might form a functional network mediating sensitization to stimulus deviance during anticipatory anxiety.During a state of behavioral inhibition, stimulus novelty or deviance may be especially salient, driving an organism into an extremely cautious stance and poised to activate fight-flight mechanisms based on further evaluation of the perceived danger (Blanchard et al., 2001;Gray, 1982;Gray and McNaughton, 2000). Heightened responses to stimulus novelty may be governed by mechanisms related to sensitization processes in clinical anxiety disorders such as post-traumatic stress disorder (PTSD, American Psychiatric Association, 2000;Siegmund and Wotjak, 2006). This study aimed to identify human brain regions that show enhanced responses to stimulus deviance during a state of anticipatory anxiety. We studied this contextspecific, increased salience of stimulus deviance in humans by using an instructed threat paradigm in which periods of potential threat (i.e., unpredictable electric shocks) and periods (Grillon, 2002;Grillon et al., 2004). To characterize the neural structures involved in sensitization to stimulus deviance, we used spatially-filtered magnetoencephalography (MEG) or adaptive beamformer analyses to estimate the volumetric distribution of source power across the brain (Hillebrand et al., 2005;Robinson and Vrba, 1999).Our procedure consisted of a passive oddball auditory task in which partici...

show abstract

“…These results suggest that an attentional stance focused toward an anticipated threat source is specific to situations in which the threat is relatively imminent and predictable. When the threat is relatively remote, sustained anxious arousal may lead to general attentional facilitation of sensory processes in all modalities (Baas, Milstein, Donlevy, & Grillon, 2006;Cornwell et al, 2007).…”

Section: Discussionmentioning

confidence: 99%

Modality-Specific Attention Under Imminent But Not Remote Threat of Shock

et al. 2008

Self Cite

View full text Add to dashboard Cite

Theories of animal defensive behavior postulate that imminent, predictable threat elicits highly focused attention toward the threat source, whereas remote, unpredictable threat elicits distributed attention to the overall environment. We used threat of shock combined with measurement of prepulse inhibition of the startle reflex to test these claims in humans. Twenty-seven participants experienced periods of threat and safety. Threat and safe periods were short or long, with the short threat periods conveying relatively predictable, imminent shocks and the long threat periods conveying unpredictable shocks. Startle reflexes were elicited with equal numbers of acoustic probes presented alone, preceded by a tactile prepulse, or preceded by an auditory prepulse. We observed enhanced tactile relative to auditory prepulse inhibition during short threat periods only. This finding supports the notion that imminent threat, but not remote threat, elicits attention focused toward the relevant modality, potentially reflecting preparatory activity to minimize the impact of the noxious stimulus.Whether aversive stimuli are predictable or unpredictable in time is a critical determinant of how an organism will adaptively respond to, and what neural structures will be activated by, threatening conditions. Studying rodents, Walker and Davis (1997) have distinguished between phasic fear, which is mediated by the amygdala in response to cues predicting imminent noxious stimulation, and sustained anxiety, which is mediated by the bed nucleus of the stria terminalis (see Davis, 1998Davis, , 2006. Along these lines, abundant evidence suggests that humans can be instructed or conditioned to fear discrete cues that predict aversive stimuli (e.g., shock) and to show anticipatory anxiety when aversive stimuli are presented unpredictably (i.e., without a discrete warning cue; Grillon, Ameli, Woods, Merikangas, & Davis, 1991;Grillon, Baas, Lissek, Smith, & Milstein, 2004). Recent studies of humans have demonstrated that these responses or states are dissociable pharmacologically Grillon, Cordova, Morgan, Charney, & Davis, 2004). In the present study, we intended to elaborate the distinction between fear and anxiety by demonstrating differences in cognitive processes under conditions of predictable versus unpredictable shock. In particular, we examined how attention is allocated under short (10 s) periods with relatively predictable timing of shock delivery and long (60 s) periods with more unpredictable timing of shock delivery.The concept of threat imminence has figured prominently in theories of animal defensive behaviors (Blanchard & Blanchard, 1989;Fanselow, 1994;Gray & McNaughton, 2000) and (Lang, Bradley, & Cuthbert, 1997;Öhman, Hamm, & Hugdahl, 2000). One common theme is that when potential threat exists but is not imminent, attention is heightened, but not necessarily directed toward specific aspects of the environment (Blanchard & Blanchard, 1989;Fanselow, 1994). An organism may show cautious approach and be highly sensit...

show abstract

Brainstem Correlates of Defensive States in Humans

Cited by 71 publications

References 26 publications

Uncertainty is associated with increased selective attention and sustained stimulus processing

Uncertainty is associated with increased selective attention and sustained stimulus processing

Neural responses to auditory stimulus deviance under threat of electric shock revealed by spatially-filtered magnetoencephalography

Modality-Specific Attention Under Imminent But Not Remote Threat of Shock

Contact Info

Product

Resources

About