New study into gender and anxiety

Women suffer from anxiety, including specific phobia, at about twice the rate of men.  Mohamed Kabbaj (Florida State University) has won a $1.8 million grant from the National Institute of Mental Health to look into these sex differences.  He will be investigating, among other things, the role of testosterone and a gene designated zif268, or 'zif' for short.

Pedestrian Thinking

"Unlike the street signs in most cities (including New Orleans) that are attached to poles and displayed high, these can’t be seen by drivers. These are designed for pedestrians, and perhaps bikers, using sidewalks. They reflect a time when planners were designing the city for people on foot." [from Sociological Images]

EXPERIMENTAL REPORT: Wanna drive?

TITLE: Wanna drive? driving anxiety and fear in a New Zealand community sample
AUTHOR: Taylor, J & Paki, D.
JOURNAL: New Zealand Journal of Psychology, July 2008
ABSTRACT: "Driving anxiety can impact everyday functioning and is common following motor vehicle crashes. However, no research has investigated its general community prevalence, despite the consistent finding that driving anxiety is not always a function of a vehicle crash. The present study explored the frequency and characteristics of driving anxiety and fear in a general community convenience sample of 100 participants who completed a questionnaire about driving anxiety, avoidance behaviour, and types of driving-related cognitions. Most of the sample described no anxiety, fear, or avoidance in relation to driving. However, 8% reported moderate to extreme anxiety about driving, and 7% described moderate to extreme driving fear. Women reported more driving anxiety, fear, and avoidance than men. These results indicate the need for more formal methods of establishing prevalence to clearly ascertain the extent of population-based driving anxiety and fear and its effects, so that research can begin to focus on developing effective treatment approaches for those whose anxiety has a psychological and functional impact." [full text]

MY TAKE: This study is trying to find out how common driving anxiety is in the general public.  Moderate to severe anxiety (significant enough to have a noticeable effect on their life) was found in 8% of the sample. I think that would have to be considered a pretty large proportion. As is usually the case driving anxiety was more common in women, although general trait anxiety was the same in both genders. The situations rated as most stressful were being tailgated, motorways, fog and heavy traffic.

EXPERIMENTAL REPORT: Driver stress and performance on a driving simulator

TITLE: Driver stress and performance on a driving simulator
AUTHOR: Matthews, G., Dorn, L., Hoyes, T.W., Davies, D.R., Glendon, A.I., Taylor, R.G.
JOURNAL: Hum Factors. 1998 Mar;40(1):136-49.
ABSTRACT:  "Effects of stress on driving performance can depend on the nature of driver's stress reactions and on the traffic environment. In an experimental study, we assessed multiple dimensions of vulnerability to driver stress by a questionnaire that was validated in previous field studies and related those dimensions to performance on a driving simulator. Results were broadly consistent with prediction. A dimension of habitual dislike of driving was associated with reduced control skills, greater caution, and disturbance of moods. A measure of aggressive driving predicted more frequent and more error-prone overtaking, which are effects attributed to the use of confrontive coping strategies in interaction with other vehicles. An alertness measure predicted speed of reaction to pedestrian hazards. This research has practical applications for system design, automated monitoring of driver performance, selection and assessment of drivers, and training."
 
MY TAKE ON IT: One thing that seems to be missing for discussion of driving phobia is the extent to which it is not purely irrational.  This study shows that dislike of driving was associated with having poorer driving control skills making more frequent driving errors, caution when driving and stress. The suggestion is that stressed drivers might not have any more accidents, but this may be not because they have normal skill levels, but because the avoid taking risks.

OBSERVATIONAL REPORT: A cerebellar-vestibular explanation for fears/phobias

The vestibular system consists of three semi-circular canals filled with liquid and two "otoliths" that are located in the inner ear. These structure tell us how we are positioned and space and allow us to judge how we are moving through space. Malfunctions of the vestibular system can cause vertigo, nausea, dizziness and inability to balance. Levinson suggests that vestibular disfunction may predispose people to develop many kinds of phobia.

TITLE: A cerebellar-vestibular explanation for fears/phobias: hypothesis and study
AUTHOR: Levinson HN
JOURNAL: Perceptual and Motor Skills. 1989 Feb;68(1):67-84.
ABSTRACT: "To clarify and test the cerebellar-vestibular (CV) basis of fears/phobias, responses of 4000 learning disabled children, adolescents, and adults with neurological and electronystagmographic (ENG) evidence of CV-dysfunction were analyzed for anxiety-related symptoms. Of this sample, 64.6% indicated fears/phobias; females were significantly more predisposed; mixed-handedness was significantly related to fears of heights and reduced vestibular response or asymmetric vestibular functioning. Also, adults had a higher incidence of the specific fears/phobias characterizing agoraphobia than children and adolescents. Analysis of factors reported as triggering the fears/phobias led to (1) a classification and theory of fears/phobias, obsessions/compulsions, and related anxiety symptoms based on realistic or traumatic, neurotic, and CV- or other CNS-based mechanisms rather than on DSM-III--R surface descriptions; (2) an understanding of the relationships between mitral valve prolapse, agoraphobia and panic episodes, as well as depression; and (3) new insights into differential diagnosis and selective treatment." [full text]

The sample used in this study are not a normal cross-section of the population, but a large group of learning disabled individuals--a group where vestibular problems are more common. And the study does not have a control group which greatly limits the conclusions that can be drawn.

However it is interesting to note that anti-motion sickness medications which help stabilise the vestibular system and improve its function, seemed to help this group with their phobias.

riving anxiety was reported by 4.9% of the adults in the group, and 2% of the overall group (including children and adolescents who are less likely to be driving). The paper assesses phobias and vestibular function but does not seem to (be able to?) assess the correlation between the two and so is ultimately more suggestive than informative. However there does seem to be some grounds for suggesting that vestibular disfunction may be a predisposing factor for developing phobias including driving anxiety.

EXPERIMENTAL REPORT: Salivary cortisol response during exposure treatment in driving phobics

Whenever a person become alert and ready to react they are experiencing "stress" (all so called the fight-or-flight response). A range of responses occur including physiological stress responses that prepare the body for strenuous activity. The following study measured one aspect of this physiological response, cortisol in saliva. Cortisol (shown right) is released by a part of the adrenal gland and its main function to to increase blood sugar

TITLE: Salivary cortisol response during exposure treatment in driving phobics
AUTHOR: Alpers GW et al
JOURNAL: Psychosomatic Medicine 65:679-687 (2003)
ABSTRACT: "OBJECTIVE: Extensive research on the hypothalamic-pituitary-adrenal (HPA) axis response to stress has not clarified whether that axis is activated by phobic anxiety. We addressed this issue by measuring cortisol in situational phobics during exposure treatment. METHODS: Salivary cortisol was measured in 11 driving phobics before and during three exposure sessions involving driving on crowded limited-access highways and compared with levels measured in 13 healthy controls before and during two sessions of driving on the same highways. For each subject, data collected in the same time period on a comparison nondriving day served as an individual baseline from which cortisol response scores were calculated. RESULTS: Cortisol levels of driving phobics and controls did not differ on the comparison day. Phobics also had normal cortisol response scores on awakening on the mornings of the exposures but these were already increased 1 hour before coming to the treatment sessions. Phobics had significantly greater cortisol response scores during driving exposure and during quiet sitting periods before and afterward. These greater responses generally paralleled increases in self-reported anxiety. At the first exposure session, effect sizes for differences in cortisol response scores between the two groups were large. Initial exposure to driving in the first session evoked the largest responses. CONCLUSION: The data demonstrate that the HPA axis can be strongly activated by exposure to, and anticipation of, a phobic situation." [abstract and full text]

TAKE HOME MESSAGE: People with a driving phobia suffer measurable physiological stress which starts in anticipation of the driving session and lasts for some time afterwards.

D'uh.

I'm sorry, but anyone suffering from a phobia can feel for themselves the racing heart rate, sweaty palms and all the classic symptoms of a physiological stress response. So even after reading the introduction to this paper (which outlined previous studies that had question the existence of a full stress response as part of phobic anxiety) I am having some trouble seeing this as a matter that was in an serious doubt. Inconsistent results are most likely caused by the fact that accurately measuring cortisol is a relative skilled task. Also cortisol is an good measure or stress experience over the course of minutes or hours, and people experiencing chronic stress might not show normal responses.