Early Experience and Postembryonic Maturation of Body Patterns in Cuttlefish (Sepia officinalis).

This study investigates effects of the environment on the maturation of body patterns in cuttlefish (Sepia officinalis). Cuttlefish were reared either individually on a uniform background, which the authors have termed uniform-solitary conditions (Group A), or grouped on variegated backgrounds, which the authors have termed varied-social conditions (Group B). At Days 1, 15, 30, and 60, juveniles were placed individually in perceptually different testing conditions, either on small, variegated stones or on a uniform pale gray background. During development in both testing conditions, juveniles from Group B concealed themselves differently from those from Group A. Thus, it appears that the response to the background is subject to individual experience. Some hypotheses are discussed relating to the effect of early experience on the maturation of body patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of dorsal and ventral vertical lobe electrolytic lesions on spatial learning and locomotor activity in Sepia officinalis.

This study aims to analyze the effects of electrolytic lesion, restricted to either the ventral or the dorsal parts of the vertical lobe (VL), on the behavior of cuttlefish (Sepia officinalis). Two behavioral tests were performed on sham-operated and lesioned cuttlefish: assessment of locomotor activity in an open field and determination of spatial learning abilities in a T maze. The results showed that ventral lesions of the VL led to marked impairment in the acquisition of spatial learning, whereas dorsal lesions of the VL increased locomotor activity in the open field and impaired long-term retention of spatial learning. This study establishes for the first time the existence of distinct functions in the ventral and the dorsal parts of the VL in cephalopods. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of ELISA titers to infectious laryngotracheitis

Histochemical, immunohistochemical, and biochemical evidence is reported showing that the ink gland of the cuttlefish Sepia officinalis contains a calcium-dependent isoform of nitric oxide synthase as well as an NMDA R1 receptor subunit localized for the most part in the immature inner cells of the epithelial layer of the gland. These results may be taken to implicate a hitherto unrecognized regulatory role of the glutamate-nitric oxide pathway in the maturation and metabolic activity of melanin-producing cells in the cephalopod defense system.     

Schizophrenia: Effects of inheritance and rearing on reaction time.

Studied both manual and verbal reaction time in 4 selected groups of adult Ss (N = 258) in an attempt to uncover hereditary and environmental influences on the reaction time of Ss whose parents do or do not have schizophrenic disorders. The groups included (a) adoptive offspring of schizophrenic parents (adoptive index); (b) adoptive offspring of nonschizophrenic parents, but whose adoptive parents had a psychiatric record of schizophrenic disorder (cross-foster); (c) adoptive offspring of nonschizophrenic parents (adoptive control); and (d) offspring of schizophrenic parents who were reared by their biological parents (nonadoptees). Analysis of variance was used to assess the effects of rearing by a schizophrenic parent, a genetic background for schizophrenia, and interaction between rearing and genetic background. Groups opposed for genetic background for schizophrenia were not different in reaction time performance, while groups opposed for rearing by a schizophrenic parent were significantly so. Mean reaction time was slower in groups reared by a schizophrenic parent than in those reared by a nonschizophrenic parent. There was no significant interaction between rearing and genetic background for reaction time performance. (French summary) (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sign tracking in cuttlefish (Sepia officinalis).

Two groups of cuttlefish (Sepia officinalis) were used to demonstrate classical conditioning in this species and to determine whether the resulting approach response would be that of sign tracking or goal tracking. For cuttlefish in the paired condition, a flashing light was presented at one end of a long tank followed by food dropped into the center of the tank. For cuttlefish in the unpaired condition, food was dropped into the center of the tank either before or after the flashing-light stimulus. Paired cuttlefish oriented to the light, positioned themselves within striking distance, and occasionally attacked the light. Unpaired cuttlefish showed no reliable response to either stimulus. The results demonstrate that cuttlefish are capable of signal learning and that, under the conditions tested, cuttlefish sign tracked. This study begins a comparative analysis of learning in cuttlefish and offers a possible ecological advantage for sign-tracking behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental evidence for spatial learning in cuttlefish (Sepia officinalis).

Laboratory mazes were used to study spatial-learning capabilities in cuttlefish (Sepia officinalis), using escape for reinforcement. In preliminary observations, cuttlefish in an artificial pond moved actively around the environment and appeared to learn about features of their environment. In laboratory experiments, cuttlefish exited a simple alley maze more quickly with experience and retained the learned information. Similar improvement was not found in open-field mazes or T mazes, perhaps because of motor problems. Cuttlefish learned to exit a maze that required them to find openings in a vertical wall. The wall maze was modified to an arena, and simultaneous discrimination learning and reversal learning were demonstrated. These experiments indicate that cuttlefish improve performance over serial reversals of a simultaneous, visual-spatial discrimination problem. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Undernutrition by rearing in large litters delays the development of reflexive, locomotor, and memory processes in mice.

In 3 experiments with a total of 512 Swiss-Webster mice, the effects of early postnatal undernutrition on the ontogeny of several behavioral capacities of varying complexity were investigated. After birth, mouse pups in all experiments were reared in either normally nourished or undernourished conditions by maintaining litter sizes at 6 or 16, respectively. Exps I and II examined the development of adultlike patterns of swimming behaviors and spontaneous locomotor activity, respectively, as a function of litter size. The maturation of both behavior patterns was delayed by about 2 days in the 16-litter mice. In Exp III, normally-nourished and undernourished Ss received 25 trials in a shock–escape T-maze at 9, 11, and 13 days of age, followed by similar retention tests 24 hrs later. Although litter size had little effect on correct turns at each age during training, Ss reared in litters of 6 showed significant retention of prior training by 12 days of age, whereas comparable retention was not noted for the large litter mice until 14 days of age. Results suggest that nutritional deficits, imposed by rearing in large litters during the postnatal period of rapid CNS maturation, retard the development of behavioral capacities involving both unlearned and learned responses. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The development of affiliative and agonistic social patterns in differentially reared monkeys

Bonnet macaques that had been reared from 3 to 6 months of age in experimental environments that appeared to adversely affect their ability to separate from mother to explore a novel physical environment in dyadic assessments shortly after the rearing experience were tested during late adolescence, an average of 2.5 years later, under conditions of increasing unfamiliarity and complexity of the social milieu. 6 monkeys, the low-foraging-demand (LFD) group, were reared by mothers having constant easy access to food during the experimental rearing period. Another 6 monkeys, the variable-foraging-demand (VFD) group, were reared by mothers having a foraging task that varied between easy and difficult in 2-week blocks during the experimental rearing period. Although no treatment group differences were evident during the initial rearing period, during subsequent social challenges VFD monkeys exhibited a diminished capacity for affiliative social engagement relative to LFD monkeys and were socially subordinate to LFD monkeys.     

Isolation and identification of a novel Ala-Pro-Gly-Trp-amide-related peptide inhibiting the motility of the mature oviduct in the cuttlefish, Sepia officinalis

A novel myotropic neuropeptide was isolated from 110 optic lobes (OL) of mature females of the cuttlefish Sepia officinalis L. by mean of high performance liquid chromatography (HPLC). The peptide inhibits the motility of the oviduct by decreasing the tonus, the frequency and the amplitude of the contractions. The primary structure of the peptide was determined as Gly-Trp-NH2. This new dipeptide is closely related to the Ala-Pro-Gly-Trp-NH2 family first identified in gastropod molluscs. On the perfused oviduct, GWa appeared to be 3000 times more potent than APGW-amide. The processing of synthetic APGWa into GWa by diaminopeptidyl activity has been clearly observed in OL extract. Nevertheless, the analysis in MALDI-MS of HPLC OL fractions did not reveal any APGWa related peptides of the known: APGWa, KPGWa, RPGWa and TPGWa. GWa could be processed from a not yet identified APGWa related peptide.     

Rearing experience differentially affects somatic and cardiac startle responses in rhesus monkeys (Macaca mulatta).

The present study reports, for the first time, somatic and cardiac responses to acoustic startle in 2 groups of rhesus monkeys (Macaca mulatta) with different rearing experiences. Both groups showed a significant direct relationship between startle amplitude and the intensity of the acoustic startle stimulus (80-120 dB) and rapid heart rate acceleration after a 120-dB stimulus. Monkeys reared with a same-age peer (PR) showed higher startle amplitudes than those reared with their mothers (MR), consistent with rearing effects in rodents. The MR monkeys, however, showed faster heart rate acceleration of greater overall magnitude than that of the PR group. The results are discussed with regard to a monkey model for neuropsychiatric disease. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of Counter-Changing Contrast: Second-Order Apparent Motion Without Postrectification Motion-Energy Analysis or Salience Mapping/Feature Tracking.

The perception of 2nd-order, texture-contrast-defined motion was studied for apparent-motion stimuli composed of a pair of spatially displaced, simultaneously visible checkerboards. It was found that background-relative, counter-changing contrast provided the informational basis for the perception of 2nd-order apparent motion; motion began where contrast changed toward the contrast value of the background checkerboard and ended where contrast changed away from the background value. The perceived apparent motion was not attributable to either postrectification motion-energy analysis or salience-mapping/feature-tracking mechanisms. Parallel results for 1st-order, luminance-defined motion (H. S. Hock, L. A. Gilroy, & G. Harnett, 2002) suggest that counter-changing activation provides a common basis for the perception of both luminance- and texture-contrast-defined apparent motion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory fear conditioning modulates prepulse inhibition in socially reared rats and isolation-reared rats.

Prepulse inhibition (PPI) is the reduction of the startle reflex when the startling stimulus is shortly preceded by a non-startling stimulus. Previous studies have shown that PPI in rats can be enhanced by auditory fear conditioning (AFC) but weakened by isolation rearing. This study investigated whether isolation rearing affects the effect of AFC on PPI. The results show that PPI was lower in isolation-reared rats than that in socially reared rats, and it was markedly enhanced by AFC in socially reared rats. However, the AFC-induced PPI enhancement in isolation-reared rats was much lower than that in socially reared rats. Moreover, the AFC-induced PPI enhancement was blocked by intraperitoneal injection (1 mg/kg) of the selective antagonist of metabotropic glutamate receptor subtype 5 (mGluR5), 2-methyl-6-(phenylethynyl)-pyridine (MPEP), 30 minutes before AFC. The baseline startle was also enhanced by isolation rearing. Thus, isolation rearing impairs not only PPI but also the AFC-induced PPI enhancement, which depends on mGluR5 activity. This study advances the animal model for investigating both neural bases and cognitive features of schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of post-weaning environment, biological dam, and nursing dam on feeding neophobia, open field activity, and learning.

Using rats in a cross-fostering design, we examined the effects of pre- and post-weaning rearing environments on feeding neophobia, open field activity, runway training, and visual discrimination learning. Fostering had no effect on the offspring behaviors. The animals reared, post-weaning, in an enriched environment consumed more food in a novel situation, were less active in the open field, and learned the first of two discrimination tasks faster than did the animals reared in the standard condition. Inter-correlations among these measures were nonsignificant, suggesting that the effect of environment on learning cannot be reduced to temperamental factors. The deficit in learning resulting from rearing in standard environment does not, however, appear to be irreversible; animals reared in the standard condition reached performance levels on the second discrimination task characteristic of those reared in the enriched environment. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Alarm call responsivity of mallard ducklings (Anas platyrhynchos): IV. Effects of social experience.

In previous experiments on alarm call responsivity, mallard ducklings have been reared in a partially isolated condition in individual boxes that facilitate individual identification. The present study was designed to determine whether a more natural social rearing condition affects freezing behavior. In 3 experiments with mallard ducklings, rearing Ss socially in a 12-bird brood without a hen resulted in a significant reduction in alarm call responsivity. It is suggested that this reduction was caused by a decrease in the level of vocalizations uttered by socially reared Ss. Stimulating socially reared Ss with distress notes, contentment notes, or pre-exodus assembly calls reinstated high levels of freezing. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Early experience and social processes in rhesus macaques ( Macaca mulatta): I. Dyadic social interaction.

Investigated how later social behavior in 6 male and 6 female rhesus monkeys was influenced by early rearing with either an animate nonconspecific (a female dog) or an inanimate (a plastic hobbyhorse) mother-substitute. Members of each rearing group were given within-rearing-group dyadic experience in a round-robin fashion, and 6 sets of such pairings were observed. Results suggest that Ss reared with animate experience were more attuned to, and better able to anticipate, their partners' behavior, although members of both groups were clearly abnormal in the extent of their social interactions. It is suggested that the results reflect a more sophisticated development of attentional and anticipatory capabilities among Ss reared with animate companions. Implications of such stimulation within a normal mother–infant context are discussed. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time-resolved measurements of photovoltage generation by bacteriorhodopsin and halorhodopsin adsorbed on a thin polymer film

We constructed a time-resolved photovoltage measurement system and examined the photovoltage kinetics of wild-type bacteriorhodopsin, its D96N mutant, and halorhodopsins from Halobacterium salinarum and Natronobacterium pharaonis. Upon illumination with a laser flash, wild-type bacteriorhodopsin showed photovoltage generation with fast (10-100 micros range) and slow (ms range) components while D96N lacked the latter, as reported previously [Holz, M., Drachev, L.A., Mogi, T., Otto, H., Kaulen, A.D., Heyn, M.P., Skulachev, V.P., and Khorana, H.G. (1989) Proc. Natl. Acad. Sci. USA 86, 2167-2171]. In contrast, photovoltage generation in halorhodopsins from H. salinarum and N. pharaonis was significant only in the ms time range. On the basis of the photovoltage kinetics and photocycle, we conclude that major charge (chloride) movements within halorhodopsin occur during the formation and decay of the N intermediate in the ms range. These observations are discussed in terms of the "Energization-Relaxation Channel Model" [Muneyuki, E., Ikematsu, M., and Yoshida, M. (1996) J. Phys. Chem. 100, 19687-19691].     

Social competence is reduced in socially deprived rhesus monkeys (Macaca mulatta).

Rhesus monkeys deprived for some period from their mother have often served as a model for the effect of adverse rearing conditions on social competence in humans. Social competence is the capacity to react in a species-specific way to social interactions. The current study assesses whether early deprivation from peers also affects the rates of behavior and social competence in rhesus monkeys. This was studied in groups of rhesus monkeys with different rearing conditions: subadult females that were mother-only reared during their first year of life and subsequently housed with peers were compared with subadult females from five naturalistic social groups. Socially deprived monkeys showed higher rates of submission and stereotypic behaviors than socially reared individuals. In addition, they show socially incompetent behavior, since they react with agonistic behavior to nonthreatening social situations. The results suggest that this socially incompetent behavior is rooted in a general feeling of anxiety toward group companions. The authors hypothesize that anxiety negatively affects social information processing, which results in socially incompetent behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of alcohol exposure and artificial rearing during development on septal and hippocampal neurotransmitters in adult rats

The effect of alcohol exposure during the early postnatal period in the rat on the hippocampus and septal region was investigated. The alcohol group was given 5 g/kg/day of ethanol from postnatal days 4 to 10 via an artificial rearing procedure. Control groups consisted of a gastrostomy control group that was treated in the same manner as the alcohol group, but not exposed to alcohol and a suckle control group that was reared normally by dams. Between 90 and 100 days of age, the hippocampus and septal region were assayed under nonstressed or stressed conditions using HPLC with electrochemical detection. Alcohol-exposed female rats exhibited increased hippocampal noradrenaline concentrations under stressed conditions, increased septal serotonin, and 5-hydroxyindoleacetic acid (5-HIAA) concentrations under nonstressed conditions, and decreased septal dopamine concentrations under stressed conditions. Artificially reared male rats (regardless of alcohol exposure) exhibited an increase in hippocampal noradrenaline concentrations under stressed conditions; a decrease in hippocampal 5-HIAA concentrations under nonstressed conditions; and a decrease in septal noradrenaline, serotonin, 5-HIAA, and dopamine concentrations under nonstressed conditions. The results suggest that female rats may be more susceptible to alcohol exposure during the postnatal period than male rats and that male rats may be more susceptible to the effects of artificial rearing than female rats.     

Cognitive style: Problem solving by rhesus macaques (Macaca mulatta) reared with living or inanimate substitute mothers.

Cognitive style, reflected in the generation of novel solutions and the use of identifiable response strategies in problem-solving situations, was contrasted in rhesus monkeys (Macaca mulatta) reared individually with either canine companions or inanimate surrogate mothers. Four experiments were conducted over a 5-year period, examining problem solving in relatively unstructured as well as more formal situations. Results indicated that whereas the 2 rearing groups did not differ on most measures of performance, consistent response strategies were identified for the dog-raised monkeys. The results were compared with previously published data from the same monkeys demonstrating rearing group differences in abilities to engage in complex social interaction. The animate nature of the early rearing environment may facilitate the development of a cognitive style that influences problem-solving abilities in both the social and nonsocial realms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social inhibition of sexual maturation in male prairie deer mice.

Five experiments demonstrated that the sexual maturation of male prairie deer mice (Peromyscus maniculatus bairdii) (n?=?334) that were reared with other males was inhibited in comparison with that of males reared in isolation. Inhibition occurred in males reared with 9 or 4 males of the same age, as well as in those housed with 1 adult male. This phenomenon was observed after several periods of grouping, and consequently at several ages ranging from 5 wks to 4 mo. Females did not retard the sexual development of males. Results indicate that the sexual maturation of individual deer mice is modulated by the specific composition, rather than density, of the local group. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)