Wife batterers: A synesthesia subtype for domestic violence perpetrators?

Perhaps not surprisingly, wife batterers, according to a recent report by Lee et al, have a neural profile making them hyper-responsive to anything other than unqualified approval from women, particularly their female mates, to draw an overly dramatic conclusion.*  (* I’m over stating the conclusion as well as rrelying uncritically on fmri information).

What is surprising, to me at least, is that the hyper-responsive neurons are in the areas associated with perception, rather than emotion or fear.  When viewing images of aggression, wife batterers have hyper-responsive “hippocampus, fusiform gyrus, posterior cingulate gyrus, thalamus, and occipital cortex.” Huh. I would have though wife batterers have a hair trigger amygdala.

The fusiform gyrus, one of the hyper-reactive areas, also is a brain area associated with recognizing people’s faces. Spouse faces weren’t used in the Lee et al paper, but it would be interesting to run that one under the brain scanner.

The other totally surprising thing, again at least to me, is what lights up when a wife batterer see an image of aggression against women:  his precuneus . (The link is to an excellent post on precunei (precuneuses?) by Neurocritic).

Briefly (and oversimplifying) the precuneus is central in “default mode” network” of consciousness, and plays a central role in imagery. For example, the precuneus is important in integrating visual stimuli so you see one big picture, instead of several individual items in an overall image (simultanagnosia). It is also interesting that the precuneus is activated when looking at your own face and your spouse’s face, but not acquaintance faces.

So, a picture emerges: wife batterers seem to parse selective images out of images of aggression against women, and have a hyper-reactive neural response to those selctive images, rather than the image as a whole.

This is consistent with an earlier report, here, and described in an interview by Dr. David George, MD, Section Chief of Clinical and Translational Studies at the National Institute on Alcohol Abuse and Alcoholism in Bethesda, Maryland  (via Impact News,  here):

. . .Dr. George devised a basic model for understanding the psychopathology of perpetrators of domestic violence. “Perpetrators frequently misinterpret environmental stimuli, which gives rise to a perceived sense of threat,” he explained. “Sensory stimuli enter the thalamus, and from there are processed by both the cortex and the amygdala. The processing of the sensory stimuli in the amygdala is extremely fast and serves as an early warning system. The processing of the sensory stimuli in the cortex is going to be much slower and much more detailed than in the amygdala…. The cortex and the amygdala talk to each other. In certain situations, these sensory stimuli give rise to defensive behavior, autonomic arousal, and hypoalgesia…. If you talk to these people and ask them what it is like when they are hitting someone, they will tell you, ‘It feels like my hands and arms are like feathers. I have no feeling in my hands. I don’t feel as though I’m doing anything.’”

In formulating a theory for the etiology of domestic violence, Dr. George reasoned that threats trigger a conditioned fear response in perpetrators that is out of proportion to the stimulus, which may result in fear-induced aggression. ‘This misinterpretation arises from the abnormality in structures and pathways that mediate fear-induced aggression,’ he said.

As Dr. George repeports, wife batterers incorrectly process environmental stimuli, and have an involuntary response which, seemingly, is not cognitively understood and has an air of unreality. Hm. Any other conditions where there’s an involuntary response that has no cognitive explanation?

Synesthesia.

Synesthesia is one of the more highly publicized conditions where neural cross-talk results in “cross-sensory percepts; an involuntary association of, say,  colors to letters, or smells to sounds. (I’m always a bit wistful in reading about the magic lands of the synesthetes, where sounds taste like chocolate, and numbers can be girlish).

The hallmark of synesthesia is that the sensory percepts have a connection that is involuntary and consistent.  Moreover, the connections are based on information already acquired: there is no delusion or confabulation. Circuits are connected to existing sockets of neurally-encoded information.

If wife batterers have a synesthesia whereby the visual stimuli of a woman (or maybe just the spouse) results in an involuntary emotion, this sounds like synesthesia.

But can sensory cross-talk connect a visual percept and an emotion? There is one report of  affect-related cross-talk here, “denim, wax, sandpaper, and silk, evoked equally distinct emotions depression, embarrassment, relief, and contentment, respectively”.

Ok. Stay with me here: if  feeling sandpaper (say) can involuntarily evoke an emotion, can seeing an image of your spouse (say) involuntarily evoke an defensive aggression?

Perhaps for batterers, the visual stimulus of a spouse, (or women in general) is that of a visual stimulus of any object.  This makes sense if the precuneus insufficiently integrates the visual image with any emotional significance, so all that is seen is “woman with unkempt hair” rather than “woman who tended to me last time I wiped out showing off my new motorcycle.” The emotional feelings due to historical source memory are totally bypassed, except when considered cognitively — different neural pathway from precuneus to amygdala. Apparently lacking any access to source memory, the visual image shoots singularly through to the amygdala, or whatever else is involved with defensive aggression.  Why defensive aggression? Who knows, but why do synesthetes associate anything with anything?  (Although probably there is a much better explanation, based on fear pathways or something).

Another kind of synesthesia — “ordinal linguistic personification” – is instructive.  Ordinal linguistic personification is the involuntary association of animate qualities –like, gender or personality  — to linguistic units,  such as letters or numbers or day of the week.

There is, for example, a  report of one synesthete that “February is ‘an introverted female’, while F is a ‘[male] dodgy geezer’. Similarly, May is reported to be ‘soft-spoken’ and ‘girly’ while M is an ‘old lady [who] natter[s] a lot’, and while August is ‘a boy among girls’, A is a female ‘mother type’.”

Is “wife batterer” synesthesia also associating a visual stimuli of a woman (or the spouse) with a neurally encoded personality — giving rise to hostile attributional bias ? Wife batterers report that their wives, when objectively ambiguous, are hostile and attempting to harm them.  Is hostile attributional bias a form of synesthesia involving selectively ignoring the historical personality of the wife (which is unreachable in source memory pathways) and involuntarily replacing that with a neurally-encoded personality?  That neurally encoded personality would be threatening, giving immediate rise to defensive aggression observed by Dr. George’s batterers. Given the “involuntariness” that is otherwise inexplicable, no wonder there is hostile attributional bias. (Was that clear? What I mean is involuntarily giving the spouse another personality).

Ok, to wrap up this theory with the weasily disclaimer of anonymous blogger’s privilege in total speculative leaps of faith: Maybe spouse abuse is the behavior resulting from a form of synesthesia hereby dubbed, “Spouse abuse” synesthesia. Using this framework, spousal abuse is really behavior resulting from a neural wiring cross-talk problem. The visual perception of a woman (i.e., spouse) results in (a) an involuntary connection with the emotion of defensive aggression directly, or, (b) an involuntary connection ascribing a threatening personality to the visual percept, indirectly giving rise to defensive aggression and hostile attributional bias. Or, heaven forbid, both (a) and (b).

This also points to a new direction for tax-payer funded batterer intervention programs. Batterers would need less empathy-training, and more cognitive counseling explaining how their wiring works, and showing them how to recognize when they’ve slipped into their involuntary aggression/hostility attributional bias. (I don’t know how the law would handle that, but perhaps it could be like dogs who get one free bite: after the batterer is given this information, if they choose to ignore it, then they are criminalized the next time.)

Note to synesthetes: I certainly don’t mean to say synesthetes are disturbed or violent in any way;  I’m really using the term “synesthesia” as a framework to connote neural cross-talk that is both involuntary and consistent between sensory percepts.

From, Tatia M. C. Lee, Ph.D.; Siu-Ching Chan, Ph.D.; and Adrian Raine, D.Phil., “Hyperresponsivity to Threat Stimuli in Domestic Violence Offenders: A Functional Magnetic Resonance Imaging Study,”J Clin Psychiatry 70:36-45. Online Ahead of Print January 13, 2009:

Objective: While spouse abuse research has almost exclusively adopted a social perspective, an increasing body of imaging research is documenting neural contributions to violence.

Method: To test the hypothesis that wife batterers are hyperresponsive to threatening stimuli, echo-planar functional magnetic resonance imaging was employed to assess brain function of 10 male batterers and 13 male matched controls during viewing of 4 types of visual stimuli: neutral, positive affect, aggressive-threat, and aggression against women. The study was conducted from September 2005 to August 2006.

Results: Compared to controls, batterers showed significantly higher neural hyperresponsivity to the threat stimuli in the hippocampus, fusiform gyrus, posterior cingulate gyrus, thalamus, and occipital cortex (p<.001). To a lesser extent, they also showed increased activation to the aggression against women stimuli, particularly in the precuneus bilaterally (p<.001), and also increased activation to positive affect stimuli in right hemisphere orbitofrontal, anterior cingulate, and inferior parietal cortical regions (p<.001).

Conclusion: Findings indicate an affect-processing abnormality in wife batterers and suggest that hypersensitivity to mildly threatening affective provocations by their spouses may represent a neurobiological predisposition to spouse abuse in some men.

As the authors note, because spouse abuse has been a “societal” issue, no one has put a spouse abuser in an fmri before and seen what’s disconnected.

It’s about time, particularly given these appalling statistics:  33% of women murdered are murdered by their ex, and 81 percent of women, who are stalked by an intimate partner, are also physically assaulted by that partner, and 76 percent of women, who are killed by an intimate partner, were also stalked by that intimate partner.

By way of backgound, I’ve blogged about it here, here, here, here, and here.

Every time some spouse abuser offs his spouse, kids, and optionally himself, this blog gets loads of hits. When your kids go to school and there’s an empty seat, the entire community is affected. So it’s not just a “womens issue”. I think this may be one of the last frontiers of civil rights in our country.

Tags: abuse, batterer, domestic violence, family anihillation, power and control, spouse abuse, synesthesia, why do husbands kill their wives