Mechanisms Controlling Head Stabilization in the Elderly During Random Rotations in the Vertical Plane

Frequency-related response characteristics of the mechanisms controlling stabilization of the head in 10 elderly subjects were compared with response characteristics in 8 young adults. Angular velocity of the head with respect to the trunk and EMG responses of 2 neck muscles were recorded in 10 seated subjects during pseudorandom rotations of the trunk in the sagittal plane at frequencies of 0.35 to 3.05 Hz. Subjects were required to actively stabilize their heads with (VS) and without (NV) visual feedback so that voluntary mechanisms and the influence of vision could be tested. Reflex mechanisms were examined when subjects were distracted by a mental calculation task during rotations in the dark (MA). Age emerged as an influential factor in the performance of head stabilization mechanisms, and decrements in performance were even more pronounced in the older as compared with younger elderly subjects. Age effects could be seen in the (a) diminished ability to voluntarily stabilize the head, particularly with the absence of vision, (b) impaired ability to stabilize the head when cognitively distracted, and (c) appearance of a resonant response of the head. Control of head stabilization shifted from reflex mechanisms to system mechanics, probably as a result of age-related changes in the integrity of the sensory systems. The elderly's system mechanics could not effectively compensate for the disturbances, however, and instability was the result.     

Knowledge,Beliefs and Attitudes Regarding Abortion in South Africa Among a Sample of University Students

A survey study design was used to determine the knowledge of a sample of South African university students regarding the Choice on Termination of Pregnancy (CTOP) Act and their beliefs and attitudes toward abortion. A total of 146 (110 female, 36 male) undergraduate psychology students participated in the study. As part of a larger study participants were given a questionnaire on knowledge, beliefs, attitudes and practices regarding sexuality among young South Africans. The results showed that most of the students were unaware of key provisions of the Act. The data also indicated opposition to abortion except in the case of rape or when the pregnancy posed a threat to the health of the woman. It is concluded that increasing public awareness of the Act is vital not only in improving access to abortion services but also in terms of reducing the stigma that seems to be associated with abortion in South Africa.     

Correction to urošević et Al. (2012)

Reports an error in "Longitudinal Changes in Behavioral Approach System Sensitivity and Brain Structures Involved in Reward Processing During Adolescence" by Sne?ana Uro?evi?, Paul Collins, Ryan Muetzel, Kelvin Lim and Monica Luciana (Developmental Psychology, Advanced Online Publication, Mar 5, 2012, np). Figure 2 was distorted in production. The correct version is presented in the erratum. (The following abstract of the original article appeared in record 2012-05404-001.) Adolescence is a period of radical normative changes and increased risk for substance use, mood disorders, and physical injury. Researchers have proposed that increases in reward sensitivity (i.e., sensitivity of the behavioral approach system [BAS]) and/or increases in reactivity to all emotional stimuli (i.e., reward and threat sensitivities) lead to these phenomena. The present study is the first longitudinal investigation of changes in reward (i.e., BAS) sensitivity in 9- to 23-year-olds across a 2-year follow-up. Support was found for increased reward sensitivity from early to late adolescence, and evidence was found for decline in the early 20s. This decline is combined with a decrease in left nucleus accumbens (Nacc) volume, a key structure for reward processing, from the late teens into the early 20s. Furthermore, we found longitudinal increases in sensitivity to reward to be predicted by individual differences in the Nacc and medial orbitofrontal cortex (OFC) volumes at baseline in this developmental sample. Similarly, increases in sensitivity to threat (i.e., behavioral inhibition system sensitivity) were qualified by sex, with only females participants experiencing this increase, and predicted by individual differences in lateral OFC volumes at baseline. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Success and satisfaction as a function of environmental constraint and origin-pawn feelings1

This research investigated causal relationships among situational and dispositional determinants of origin-pawn (O-P) feelings and perceptions of task satisfaction and success. Seventy-seven college students performed a task under one of three conditions—freedom, moderate freedom, or high constraint. Analysis of data through multiple regression and path-analytic techniques indicated that O-P feelings are a function of both situation and disposition. While condition and O-P feelings have direct effects on both success and satisfaction, satisfaction is affected more by the situational element of freedom versus constraint than is success. The path analysis tended to support a previously conceptualized causal model of relationships among the variables.     

Longitudinal changes in behavioral approach system sensitivity and brain structures involved in reward processing during adolescence

[Correction Notice: An Erratum for this article was reported in Vol 48(5) of Developmental Psychology (see record 2012-09244-001). Figure 2 was distorted in production. The correct version is presented in the erratum.] Adolescence is a period of radical normative changes and increased risk for substance use, mood disorders, and physical injury. Researchers have proposed that increases in reward sensitivity (i.e., sensitivity of the behavioral approach system [BAS]) and/or increases in reactivity to all emotional stimuli (i.e., reward and threat sensitivities) lead to these phenomena. The present study is the first longitudinal investigation of changes in reward (i.e., BAS) sensitivity in 9- to 23-year-olds across a 2-year follow-up. Support was found for increased reward sensitivity from early to late adolescence, and evidence was found for decline in the early 20s. This decline is combined with a decrease in left nucleus accumbens (Nacc) volume, a key structure for reward processing, from the late teens into the early 20s. Furthermore, we found longitudinal increases in sensitivity to reward to be predicted by individual differences in the Nacc and medial orbitofrontal cortex (OFC) volumes at baseline in this developmental sample. Similarly, increases in sensitivity to threat (i.e., behavioral inhibition system sensitivity) were qualified by sex, with only females participants experiencing this increase, and predicted by individual differences in lateral OFC volumes at baseline. (PsycINFO Database Record (c) 2012 APA, all rights reserved).