Aversive and appetitive electrodermal classical conditioning using pictures as stimuli

The principal goal of this study was to verify whether it was possible to obtain both aversive and appetitive electrodermal classical conditioning, using pictures as conditioned stimuli (CS), and unconditioned stimuli (US). Additionally, we tried to verify whether, as a consequence of such conditioning, diminution of the unconditioned response (UR) was observed. With this aim, IAPS (?International Affective Picture System?) pictures were selected as stimuli. A picture showing a burnt face was used as the aversive US (USav), and a picture showing a scene with erotic content was used as the appetitive US (USap). As the aversive CS (CSav), and appetitive CS (CSap), two images with intermediate values of valence and arousal showing male faces were selected. In the experimental group, 10 CSav/USav and 10 CSap/USap trials were presented. In the control group 10 CSav, CSap, USav, and USap trials were presented in pseudorandom order. Skin conductance response (SCR) elicited by both the CSs and the USs was scored. Results showed aversive conditioning, but neither appetitive conditioning nor UR diminution. Problems to obtain conditioning using pictures as stimuli and possible options to overcome them in future research are discussed.     

Effect of manipulating the risetime of an acoustic stimulus on two protective reflexes: cardiac defense and motor startle

Effect of manipulating the risetime of an acoustic stimulus on two protective reflexes: cardiac defense and motor startle. The risetime is a parametric characteristic of the eliciting stimulus frequently used to differentiate among psychophysiological reflexes. The aim of the present study was to examine the effect of manipulating the risetime of an acoustic stimulus on two protective reflexes: cardiac defense and motor startle. 100 participants underwent a psychophysiological reactivity test to five presentations of an intense acoustic stimulus (105 dB white noise) under one of five risetime conditions: 0, 24, 48, 96, and 240 ms. Total energy of the stimulus was controlled by increasing the base duration of the stimulus (1000 ms) by one third of the risetime. Results showed that risetime significantly affected motor startle but not cardiac defense. Startle amplitude decreased linearly with increasing risetime after 24 ms. On the other hand, repetition of the stimulus significantly affected cardiac defense but not motor startle. These results question the traditional differentiation between startle and defense based on risetime.     

Effects of personal causation and perceived control on responses to an aversive environment: The more control,the better

A laboratory experiment was conducted to investigate the effects on reactions to aversive noise of three types of personal control: control over the initiation of noise, control over its termination, and combined control over both initiation and termination. On an attention-to-detail measure which occurred concurrently with noise stimulation, subjects' error rates decreased linearly as degree of control increased. Likewise, on a post-noise measure of task persistence, subjects' performance rates increased linearly across the three conditions as degree of control increased. Results were discussed in terms of Seligman's theory of learned helplessness and deCharms' theory of personal causation, and the motivational effects of personal control were emphasized.     

The influence of instructive feedback presentation schedule: A replication with children with autism spectrum disorder

Instructive feedback (IF) is a modification to discrete trial instruction that may increase instructional efficiency for individuals with autism spectrum disorder. Several variations of IF have recently been evaluated in the literature; however, few studies have assessed the effectiveness and efficiency of presenting secondary targets on continuous versus intermittent presentation schedules. The current study evaluated the effectiveness and efficiency of various presentation schedules of secondary targets during discrete trial instruction. Specifically, we replicated and extended Griffen et al. (1998) by comparing a condition in which secondary targets were presented during each trial of a session, a condition in which secondary targets were presented every other trial, and a condition in which secondary targets were presented about every 4 trials. Within-subject replications were included for both participants. One of the intermittent presentation schedules was associated with the most optimal outcomes in all 4 comparisons.     

Grooming and yawning trace adjustment to unfamiliar environments in laboratory Sprague-Dawley rats (Rattus norvegicus)

The authors studied grooming and yawning caused by mild stress in laboratory Sprague-Dawley rats (Rattus norvegicus). Two groups received 3 and 6 sequences of 5 foot shocks at random intervals (RI) and fixed intervals (FI), respectively. A 3rd group was not shocked (NS). The groups were exposed for 60 min twice. Grooming did not differ among groups, but yawning diminished with RI. Yawning increased and grooming decreased with the 2nd exposure, except in RI in which grooming increased. In NS and FI, grooming prevailed during the first 20 and 30 min, respectively, whereas yawning dominated the remainder of the time. In RI, grooming occurred more than yawning. An upward shift on this scale causes grooming to substitute yawning, whereas a downward shift causes the reverse effect.     

The Aggression Questionnaire: a validation study in student samples

The goal of this study was to examine the psychometric properties of the Aggression Questionnaire (AQ) in Spain. The AQ is a 29-item instrument designed to measure the different dimensions of the hostility/anger/aggression construct. It consists of 4 subscales that assess: (a) anger, (b) hostility, (c) verbal aggression, and (d) physical aggression. In Study 1, reliability, construct validity, and convergent validity were evaluated in a group of 384 male and female university students. Test-retest reliability was evaluated using a group of 154 male and female university students. The results of the factor analysis were similar to the scale structure claimed for this instrument. The subscales also showed internal consistency and stability over time. The AQ and its subscales were also compared with the scales and subscales of the Spielberger State-Trait Anger Expression Inventory (STAXI), the Cook-Medley Hostility Scale (Ho), the Buss-Durkee Hostility Inventory (BDHI), and the Jenkins Activity Survey-Form H (JASE-H). The results show that the AQ evaluates some aspects of anger, such as Anger-Trait and Anger-Out, rather than other elements, such as Anger-In or Anger-State. In Study 2, two new male groups were used to evaluate the criterion validity of the AQ: 57 prison inmates and 93 university students, finding that this instrument discriminated between the scores obtained by common offenders and university students.     

Long-term memory for 400 pictures on a common theme

Long-term memory for large numbers of color photographs with a common motif--doors--was studied using pictures with two levels of informative cues: original photographs, and edited pictures in which extraneous information on details such as vegetation, paint scratches, signs, and lamp posts was removed. In the study phase, subjects viewed 400 pictures and were subsequently tested for memory on two-alternative forced-choice discriminations between studied and distracter pictures from the same picture category, at retention intervals between 0.5 h and 9 days. When tested with the nonedited original photographs immediate memory performance was close to 85% correct; when pictorial details were removed memory performance dropped by 20%. The decay functions were shallow with parallel paths for the categories of pictures. It is concluded that specific details of visual scenes contributed to long-term memory of those scenes.     

Psychophysiological mechanisms involved in the affective regulation and food restriction of women at risk of suffering from bulimia nervosa

The aim of the study was to explore the effect of visualizing food images under different mood states and food restriction conditions on the emotional modulation of two defense reflexes (startle reflex and cardiac defense). 72 women at risk of suffering from bulimia nervosa were assigned to two groups: 1) a group under induced positive, neutral, or negative mood state and, 2) a 6-hour-food-deprived group or a non-deprived group. Second-by-second heart rate and electromyogram activity from the orbiculari oculi region were recorded after the auditory stimulus. The results showed that, while viewing food images, non-deprived women under negative mood state potentiated the cardiac defense response and the startle motor reflex. Results are discussed in the context of emotional eating theories and Peter Lang's motivational priming model.