Demystifying success : critical reflections of African-American California community college students about factors leading to scholastic success during the first year

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The visual perception of motion

Sensing the movements of the world and the objects within it appears to be a fundamental job for our visual system. In rare cases of brain damage, we find that individuals lacking motion perception live in a very different world of frozen images, where simple tasks like filling a kettle or crossing the road take on alarming difficulties. That tasks such as driving a fast car down the freeway require a good sense of the movements of yourself and other objects are obvious, but motion information is used in many less obvious ways. For example, it may seem a trivial task to us to follow a moving object with our eyes, but without motion perception these smooth pursuit eye movements are not possible. One way to show this is to have people attempt to move their eyes smoothly along a line etched on a wall. At the same time we place a very bright light just under this line. The bright light burns an afterimage into the retina which can then be examined at leisure. In attempting the eye movement we find that the afterimage is not a smooth line but a series of ‘dots’. This is because you find it difficult to smoothly move yours eyes along the line – even more so if it is vertical – instead flicking your eyes in a series of small, fast jumps known as saccades. Each dot represents the alighting point of a saccade and each gap the distance moved by the saccade. Now, if the line is replaced with a moving dot and we try to track this, the resulting afterimage is a smooth line. This shows that our eyes moved at a constant rate so that the very centre of our vision, where it is best at seeing fine detail, remained focused on the target. Not surprisingly, damage to areas of the brain involved in analysing the moving image destroys this ability

The effect of contrast adaptation on briefly presented stimuli

AbstractWilson and Humanski (1993) have recently reported evidence that adapting to low temporal frequency sinewave gratings yields little threshold elevation for briefly presented test stimuli. We postulated that brief stimuli may be detected by a transient channel which would be minimally affected by a low temporal frequency adapting pattern. We therefore measured the effect of adaptation om briefly presented test stimuli for a wider range of adapting temporal frequencies. The results indicate that adaptation may yield threshold elevation for briefly presented stimuli and that threshold elevation is greater for high than low temporal frequency adapting patterns. These results are consistent with the hypothesis that briefly presented stimuli are detected by a transient channel

Psychopathy and impulsivity: The relationship of psychopathy to different aspects of UPPS-P impulsivity

Impulsivity is thought to be a major component of psychopathy. However, impulsivity is a multi-faceted concept, and different facets may have differential relationships to psychopathy. We measured impulsivity via the UPPS-P in a sample of prisoners and in patients in a personality disorder service resident in secure psychiatric care. Psychopathy in the prison sample was measured via the clinician-rated Psychopathy Checklist: Screening Version and in the patients via the Psychopathy Checklist-Revised. We found that the Lifestyle/Antisocial factor (Factor 2) was associated with acting rashly when emotional (Negative Urgency and Positive Urgency). However, the Interpersonal/Affective factor (Factor 1) was associated with reduced impulsivity in the domains of premeditation and perseverance, and its unique variance was also associated with less rash behaviour. The Interpersonal facet (Facet 1) was particularly associated with reduced impulsivity. The results show that individuals with high Interpersonal traits of psychopathy can plan carefully and are persistent in their goals. This may underpin instrumental violence and criminal behaviour. Thus, a simple unitary understanding of the relationship between psychopathy and impulsivity may not be valid and may distort the multifaceted relationship between the two concepts that could assist in the assessment and management of psychopathic offenders

Psychopathy and impulsivity: The relationship of psychopathy to different aspects of UPPS-P impulsivity

Impulsivity is thought to be a major component of psychopathy. However, impulsivity is a multi-faceted concept, and different facets may have differential relationships to psychopathy. We measured impulsivity via the UPPS-P in a sample of prisoners and in patients in a personality disorder service resident in secure psychiatric care. Psychopathy in the prison sample was measured via the clinician-rated Psychopathy Checklist: Screening Version and in the patients via the Psychopathy Checklist-Revised. We found that the Lifestyle/Antisocial factor (Factor 2) was associated with acting rashly when emotional (Negative Urgency and Positive Urgency). However, the Interpersonal/Affective factor (Factor 1) was associated with reduced impulsivity in the domains of premeditation and perseverance, and its unique variance was also associated with less rash behaviour. The Interpersonal facet (Facet 1) was particularly associated with reduced impulsivity. The results show that individuals with high Interpersonal traits of psychopathy can plan carefully and are persistent in their goals. This may underpin instrumental violence and criminal behaviour. Thus, a simple unitary understanding of the relationship between psychopathy and impulsivity may not be valid and may distort the multifaceted relationship between the two concepts that could assist in the assessment and management of psychopathic offenders

Self-esteem, narcissism, and aggression: different types of self-esteem predict different types of aggression

The aim of this study was to examine the relationship between self-esteem, narcissism, and measures of proactive and reactive aggression in two large community samples of young adults from two countries (the United Kingdom and Malaysia). Self-esteem and narcissism were measured through the Multidimensional Self-Esteem Inventory and the Narcissistic Personality Inventory, whereas aggression was measured by the Reactive–Proactive Aggression Questionnaire in 501 young adults with approximately equal numbers of men and women. In both countries, low levels of self-esteem were associated with reactive aggression while high levels of narcissism were associated with proactive aggression. Although this pattern was similar for both genders, the associations between both types of self-evaluation and proactive aggression were greater for men. The results suggest that people with low self-esteem are prone to greater reactive aggression due to anger and hostility, whereas those with high levels of narcissism can act with deliberate, planned aggression to achieve a goal. These effects appear stable across gender and culture

Enhanced emotional response to both negative and positive images in post-traumatic stress disorder: Evidence from pupillometry

Post-traumatic stress disorder (PTSD) is characterised by alterations in the function of the autonomic nervous system. However, it is unclear if this dysfunction is threat-related or related to arousing stimuli in general. Pupillometry offers a simple non-invasive measure of ANS activity that can separate parasympathetic and sympathetic arousal. Participants viewed images with emotional or neutral content: 20 met diagnostic criteria for PTSD, 28 were trauma-exposed (but with no PTSD), and 17 were controls. Initial pupil constriction (a marker of parasympathetic function) was reduced for the PTSD group, while dilation due to the emotional content of the image (a marker of sympathetic activity) was greater in the PTSD group. Individuals with PTSD demonstrated enhanced physiological arousal to both threat-related and positive images. The results suggest reduced parasympathetic arousal and increased sympathetic arousal in the autonomic nervous system, which has been linked to a range of adverse health outcomes in PTSD