Conclusions: These findings suggest that a mild real life stressor iscapable of producing complex changes in major cardiovascular regu-latory mechanisms and that susceptibility to stress would presum-ably be affected by trait anxiety.

This work was supported by the Ministry of Education and Scienceof the Russian Federation (grant number 2.2.3.3/2028).

doi:10.1016/j.ijpsycho.2010.06.111

Trait anxiety and peripheral vascular response to mental stress inmales: Handedness-related differences

Zlatislav Stoyanov, Piareta NikolovaDepartment of Physiology and Pathophysiology; Medical University“Prof. Paraskev Stoyanov”, Varna, Bulgaria

Background. Human response to mental stress is a complexproduct of cognitive processes, emotions and central-autonomicintegration. Evidence suggests that physiological dimensions ofstress-response may be influenced by personality traits, includinganxiety. It is well known that handedness-related differences inpersonality exist. Whether these differences are projected into stressresponse is unclear. The aim of the present study was (1) to examinethe correlation between trait anxiety (TA) scores and changes ofvascular tone during mental stress in right- and left-handers, and (2)to compare the stress-induced changes of vascular tone in low-anxious and high-anxious right-handers and in low-anxious andhigh-anxious left-handers.

Methods. Sixteen right-handed and 16 left-handed males between20 and 22 years of age were studied. Handedness was assessed by theEdinburgh Inventory. The trait scale of Spielberger–Hanin State-TraitInventory was used for assessment of TA. By means of infraredphotoplethismographic (PPG) probe, the peripheral blood flow wasmonitored and recorded at rest and during mental stress. The mentalchallenge was a combination of memory and arithmetic tasks. Thechanges of vascular tone were judged by the changes (baseline-to-task) of the photoplethismographic indicator “module of elasticity”(ME, in relative units) — “a/Т”, where “a” is the duration (in ms) ofthe ascending part of the PPG-wave, and “T” is the duration (in ms) ofthe whole PPG-complex. The increased values of ME testify to anincrease in tonic tension of blood vessels.

Results. At mental rest, МЕ had equal values in both groups:16.1±2.5 in right-handers and 16.8±3.5 in left-handers (bothvalues were within the norm of 13 to 19 relative units). TheTA scores did not correlate significantly with the baseline valuesof ME. During mental stress, ME increased significantly in right-and in left-handers: up to 20.3±4.0 (t=3.561, p=0.001) and to22.2±4.2 (t=3.948, p<0.001) respectively. Only in right-handersdid TA scores correlate significantly with ME values during mentalload (r=0.732, p=0.001) and with baseline-to-task changes inME (r=0.601, p=0.01). The mean change of ME (i.e. vascularreactivity) was greater in high-anxious right-handers than in low-anxious ones (0.446 vs. 0.094; t=4.530, p<0.001). Such sig-nificant relationships have not been found in left-handers.

Conclusions. The obtained results indicated that vascular reactiv-ity to mental stress may be significantly influenced by trait anxietyonly in right-handed males. On the basis of the observed handed-ness-specific relationship between trait anxiety and stress response,it can be hypothesized that there exists handedness-related differ-ences in brain integration of cognitive processes, emotions, andautonomic control during mental stress.

doi:10.1016/j.ijpsycho.2010.06.112

Finger length ratio (2D:4D) and peripheral vascular response tomental stress in males

Zlatislav Stoyanova, Kiril Hristozovb, Irina Pashalievaaa Department of Physiology and Pathophysiology, Medical University“Prof. Paraskev Stoyanov”, Varna, Bulgariab Clinic of Endocrinology, University Hospital “St. Marina”,Varna, Bulgaria

Background. It is well known that sex differences in cardiovas-cular reactivity to mental stress exist. These differences may berelated, partly at least, to differences in actual levels and ratios ofsex steroids in males and females. At this time, however, it isunknown whether prenatal levels of sex steroids and theirorganizational effects on the brain (especially of testosterone) arerelated to the cardiovascular stress-responses later in life. Anindirect biomarker for the prenatal testosterone/estrogen ratio isthe ratio between the lengths of the 2nd and 4th fingers of thehand (2D:4D). Low 2D:4D ratio testifies to high prenatal testoster-one/estrogen ratio (high prenatal levels of androgens), and viceversa—high 2D:4D indicates low prenatal testosterone/estrogenratio (low prenatal levels of androgens). In the present study, weset the following goals: (1) to examine the correlation between2D:4D and vascular reactivity to mental stress, and (2) to comparethe values of 2D:4D in low reactors and high reactors to mentalstress.

Methods. Twenty young men, aged between 20 and 22 years,were studied. The fingers' length was measured on photocopies ofthe ventral surface of the hands. Three measures of 2D:4D werecalculated and analyzed: right hand 2D:4D, left hand 2D:4D, and thedifference between right and left 2D:4D (Dr-l). By means of infraredphotoplethismographic (PPG) probe, the volume changes of periph-eral blood flow were recorded at rest and during mental stress. Themental challenge was a combination of memory and mentalarithmetic tasks. Vascular reactivity to mental stress was evaluatedthrough the baseline-to-task changes of the PPG index “module ofelasticity” (ME) — “a/Т”, where “a” is the duration (in msec) of theascending part of the PPG-wave, and “T” is the duration (in ms) of thewhole PPG-complex. The increased values of ME testify to an increasein tonic tension of blood vessels.

Results. A significant negative correlation (r=–0.508; p=0.02)was found between right hand 2D:4D and baseline-to-task changes ofME. Similar to it was the association between Dr-l and vascularreactivity (r=−0.404; p=0.08). In the high reactors group, themean values of right hand 2D:4D (0.949) and Dr-l (−0.005) werelower than in the low reactors group (0.970 and 0.012 respectively),but the differences were insignificant.

Group Right hand 2D:4D Left hand 2D:4D Dr-l

Low reactors 0.970 0.958 0.012High reactors 0.949 0.954 −0.005

Conclusions. The obtained results reveal a relationship betweenvalues of 2D:4D and vascular reactivity to mental stress in males. Thedata suggest that higher intrauterine levels of androgens or a higherprenatal testosterone/estrogen ratio (both presented as lower 2D:4D)are associated with higher vascular reactivity to mental stress later inlife. Further research is needed to clarify whether the prenatalorganizational effects of sex steroids are directly responsible for sucha relationship or if the effect is mediated by androgen dependentpersonality traits.

doi:10.1016/j.ijpsycho.2010.06.113

271Abstracts / International Journal of Psychophysiology 77 (2010) 239–287