Ontogeny of behavioral arousal: The role of environmental stimuli.

During the course of ontogenesis the developing rat has been reported to pass through a transient period of intense behavioral arousal which peaks at 15 days of age, a phenomenon that has been interpreted to reflect a sequential caudal to rostral development of excitatory and inhibitory systems in the mammalian brain. In the present 4 experiments with male and female Sprague-Dawley rats, it was shown that (a) this period of intense hyperactivity occurred only when the animal was tested alone in an unfamiliar environment, the degree of arousal was proportional to the dissimilarity between the home cage and the test environment, and isolation per se was insufficient to elicit the arousal response; (b) environmental temperature had a minimal influence on the degree of behavioral arousal in either familiar or unfamiliar environments; (c) unlearned responses to pheromonal or other naturally occurring nest odors did not suppress the high levels of locomotor activity evoked by unfamiliar environments in the 15-day-old rat pup; and (d) it is fear or distress evoked by the unfamiliar environment rather than curiosity that underlies this developmental phenomenon. It is concluded that the sequential increase and decrease in locomotor activity that occurs during ontogenesis cannot be used to support the principle of caudal to rostral development of excitatory and inhibitory centers in the CNS. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

References used in a drug information centre

The literature sources used in 461 consecutive problem-oriented questions submitted during 1993 to a Drug Information Centre were reviewed retrospectively. Journals were the most frequently used literature source (36% of all quotations). Commonly used medical and clinical pharmacology journals, together with standard textbooks, provided the necessary information to solve more than 50% of drug information requests. Most questions could be answered by including the complementary use of the question/answer database Drugline. Drug information access is important for the improvement of rational use of drugs. According to the present study, this activity is possible with a fairly limited number of sources.     

Blood lipids in metropolitan caracas school children. A preliminary report (author''s transl)

A study was made of EP recorded in the visual projection area of the cerebral cortex in children with normal sight and in those with disturbed refraction when presented with blank and checkered patterns, the dimensions of the chess squares equalling 10, 20, 40, 60 and 120 angular minutes. In children with normal sight the patterns were defocussed by eyeglass lenses of --1 to +/- 6 dioptries. The investigation revealed a different EP configuration on the presentation of blank and checkered patterns. There was a similarity between the EP change when a blank pattern was replaced by a checkered one, and when the checkered pattern was made sharper. It is assumed that these EP changes results from enhanced lateral inhibition due to the contrast boundaries of the checkered pattern, The experiments carried out on children with disturbed refraction indicated that the maximal EP amplitude corresponded to the optimal optic correction, which shows that theuse of EP is a promising cue in determing vision acuity.     

Frederick Duane Sheffield (1914–1994): Obituary.

Memorializes Frederick Duane Sheffield and his work, which reflected a lifelong commitment to the contiguity theory of learning under the tutelage of E. R. Guthrie. His published experimental work and interactions with colleagues and students during his career at Yale are highlighted. Sheffield is remembered for his 1951 Psychological Review article, "The Contiguity Principle in Learning Theory," in which he defended and expanded Guthrie's views, and for his criticism of the need and drive-reduction theories that dominated Yale in the 1940s. In 3 experiments in the early 1950s, he showed that neither need nor drive reduction was necessary to induce learning. The findings were interpreted as showing that it was the onset of stimulation, not the reduction in drive or need, that was reinforcing. This became broadly known as Sheffield's drive-induction theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult attachment classification and self-reported psychiatric symptomatology as assessed by the Minnesota Multiphasic Personality Inventory--2.

This study examined differences in self-reported psychiatric symptomatology on the Minnesota Multiphasic Personality Inventory-2 according to adult attachment status on the Adult Attachment Interview in first-time mothers from a high-risk poverty sample. Participants reported fairly high levels of symptomatology regardless of attachment status. The dismissing adult attachment group reported comparatively little psychiatric distress, emphasized independence, and scored the lowest on self-reported anxiety. The preoccupied group was highest on a range of indices of psychiatric symptoms indicative of self-perceived distress and relationship problems. The autonomous group's scores ranged between the scores of the other 2 groups on most scales. These different symptom patterns are consistent with adult attachment status as an index of self-representation and as a set of strategies for processing emotions and thoughts related to distress and to attachment relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Issues in the neuropsychological assessment of children with learning disabilities.

Describes an approach to the neuropsychological assessment of children with learning disabilities. Issues relating to the aims of the assessment, test selection, stylistic variables in assessment, test interpretation, and the rendering and implementation of recommendations are discussed. Some comparisons with other strategies and modes of approach (e.g., level of performance, pathognomonic sign, and differential score approaches) are included. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Opioid-reinforced operant behavior: Selective suppression by alpha-methyl-para-tyrosine.

Conducted 4 experiments using a total of 24 Charles River male albino rats. Morphine-addicted Ss performed operant responses for opioid or milk rewards. When Ss were then denied access to opioids, abstinence symptoms developed. Responding under extinction conditions 2 wks after opioid withdrawal provided a measure of the "relapse" tendency. Systemic administration of alpha-methyl-para-tyrosine, an inhibitor of catecholamine synthesis, suppressed these responses if they had been reinforced by an opioid but not if they had been established with milk reinforcement. This indicates that the integrity of the catecholamine systems is vital for relapse to occur. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ontogeny of amphetamine anorexia in rats: A behavioral analysis.

Conducted 4 experiments with 246 Sprague-Dawley rats to ascertain the effects of dextroamphetamine (DAM; 1 or 2 mg/kg) on the behaviors associated with feeding in weanling and preweanling rats. The 1st 2 experiments produced the following results: (a) In 5-day-old Ss, DAM increased speed of approach to an anesthetized mother; (b) at 15 days of age, DAM increased speed of approach to the mother and produced marked weight loss (relative to the weight of controls), slowed or reduced frequency of attachment to the nipple, and decreased time spent nursing; and (c) at 25 days of age, DAM disrupted all aspects of the feeding process except initial approach. Weight gain, time spent in contact with the mother, time spent nursing, and time attached to the nipple were all reduced by the drug. In Exps III and IV, milk was delivered to Ss at 5, 15, and 25 days of age through tongue cannulas, which allowed ingestion without suckling. Under these circumstances, DAM produced clear-cut anorexia in Ss of all 3 ages. It is concluded that in early development, the anorectic effects of DAM are overridden by the strong suckling response that is not disrupted by the drug. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociation of arousal and regulatory behaviors following lesions of the lateral hypothalamus.

Investigated the effect of lesions of the lateral hypothalamus on feeding and spontaneous locomotor activity in 3 experiments with a total of 110 male Sprague-Dawley rats. Lateral hypothalamic lesions produced aphagia and adipsia but did not prevent the increase in locomotor activity characteristic of starvation. In addition, both food deprivation and lateral hypothalamic self-starvation potentiated amphetamine-induced behavioral arousal. However, the lesions did abolish incentive-motivated activity to a stimulus signaling food. Results suggest a dissociation between the neural mechanisms mediating arousal and regulatory behaviors. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of attention in "lie-detection."

Randomly assigned 80 male college students to 1 of 4 groups. Tape-recorded instructions directed Ss in Groups 1 and 2 to evaluate a psychological case history or a newspaper story, respectively. Group 3 read about a kidnapping after being told they were participating in a lie-detection experiment and would be questioned on the material later. Group 4 was given the same information as Group 3, but was told that they should not reveal the information when questioned. Galvanic skin responses (GSRs) were measured as Ss listened to tape-recorded questions on the material read; no verbal responses were made. The E then attempted to determine "blindly" which target information S had received by examining the GSRs. The number of Ss whose given information was successfully detected was significant in Groups 2, 3, and 4. Results suggest that simply attending to or focusing upon relevant information is a sufficient condition for detectability in a lie-detection situation. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)