Effects of extraversion and neuroticism on performance in Fitts Tapping tasks

The aim of this study was to examine the differences in performance between extraverts and introverts, as well as between neurotic and stable subjects, in Fitts’ Tapping Task (FTT). Forty subjects classified into the four personality categories according to the EPI questionnaire (10 in each), performed twelve original FTT, with the task difficulty ranging from one to six bits. The results showed the difference in performance between introverts and extraverts, but no differences were found between neurotic and stable subjects. Introverts achieved higher scores in easier tasks, while extraverts were better in more difficult tasks. The differences were attributed to summative effects of natural and task induced arousal, which resulted in an optimal level of cortical arousal in extraverts and hyper arousal in introverts at more demanding tasks. It was also found that stable introverts had the highest, and stable extraverts the lowest estimates of task difficulty assessment. Neuroticism, however, had no effects on the task difficulty

Changes in heart rate variability during working and non-working nights

Cilj ovoga istraživanja bio je usporediti razine i obrasce varijabiliteta srčane aktivnosti tijekom noćne smjene i ekvivalentnog neradnog razdoblja noći. U ispitivanju je sudjelovalo osam medicinskih sestara s Odjela za kirurgiju, Opće bolnice Zadar. Dob ispitanica kretala se u rasponu od 25 do 33 godine. Ispitivanje je uključivalo kontinuirano registriranje srčane aktivnosti tijekom 10-satnog razdoblja noćne smjene (21.00 – 07.00 sati) i tijekom ekvivalentnog neradnog razdoblja. U skladu s očekivanjem, analize su pokazale razlike u razinama srčane aktivnosti između radnog i neradnog razdoblja. Pri tome su tijekom neradnih razdoblja utvrđene veće prosječne vrijednosti i veći varijabilitet R-R intervala, odnosno naglašeniji učinak parasimpatičke regulacije srčane aktivnosti. S druge strane, obrasci promjena i spektralne kompozicije srčane aktivnosti bile su slične tijekom dvaju ispitivanih razdoblja. Dobiveni rezultati ukazali su na izraženost cirkadijurnog obrasca promjena, odnosno parasimpatičku prevalenciju tijekom radnih i neradnih noćnih r zdoblja. S obzirom da normalan rad zahtjeva aktivnost simpatičkog dijela autonomnog živčanog sustava, indikativna je parasimpatička prevalencija u srčanoj regulaciji tijekom radnog noćnog razdoblja. Navedeno se prvenstveno odnosi na razdoblja od 04.00 do 06.00 sati za koje su utvrđene iste razine parametara varijabiliteta srčane aktivnosti. Općenito se može kazati da parasimpatička dominacija tijekom radnih noći ukazuje na različitost među radnim zahtjevima i trenutnim mogućnostima organizma da ih zadovolji, što predstavlja glavni izvor stresa kod noćnog rada.The aim of this study was to compare levels and patterns of heart rate variability during working night shifts and the same period of non-working nights. Eight nurses from the Surgical Department of Zadar Hospital, aged 25-33, participated in this study. The study included continuous recordings of cardiac activity during 10 hours of night-shift working (9.00 pm – 7.00 am) and during the equivalent non-working night periods. As expected, the analyses showed differences in the levels of cardiac activity between working and nonworking nights. Non-working nights were characterised by longer R-R intervals, higher variability indices and greater parasympathetic effects on cardiac activity, while their patterns of changes and spectral compositions were rather similar to those obtained during working nights. The obtained results showed the supremacy of the circadian pattern of changes, i.e. parasympathetic prevalence, during both working and non-working nights. Parasympathetic prevalence during night shift working seemed inappropriate since normal working implies sympathetic activity. This is particularly true for the periods between 4.00 and 6.00 am, when various parameters indicated almost the same level of arousal during working and non-working nights. Certainly, the lack of sympathetic activity and parasympathetic dominance during working nights represents a discrepancy between the work requirements and the momentary capabilities of the organism to meet them. Due to this, it represents a major source of stress in night-shift working

Cardiovascular reactions to exam situations

The aim of this study was to examine whether the parameters of cardiac R-R intervals reflect the changes in the emotional and mental components of stress during a difficult and an easy exam. Twelve subjects, 18 to 19 years of age, with no previous experience with exams at university level, took part in the study. The levels of anxiety, high activation and exam apprehension were assessed before a difficult and an easy exam. Subjects’ cardiac R-R intervals were continuously registered in the period of five minutes before the exam, during the whole exam, and five minutes after the exam by the Power Lab polygraph. The level of anxiety, high activation and exam apprehension were higher before the difficult exam than before the easy exam. Shorter and more regular R-R intervals were found dur- ing the difficult exam as compared to the easy exam. No significant differences in the spectral analyses parameters were found between the difficult and the easy exam, while the differences were significant between the pre-exam, exam and the post-exam periods