Caloric diet, such as fat and sugar intake, has rewarding effects, and has been indicated to affect the responses to addictive substances in animal experiments. However, the possible association between sucrose reward and the motivation for addictive drugs remains to be elucidated. Thus, we carried out behavioral tests after sucrose self-administration training to determine the effects of sucrose experience on rats' motivation for cocaine, locomotor sensitivity to cocaine, basal locomotor activity, anxiety level, and associative learning ability. The sucrose-experienced (sucrose) group exhibited higher lever press, cocaine infusion and break point, as well as upshift of cocaine dose-response curve in cocaine self-administration test, as compared with the control (chow) group. Additionally, despite similar locomotor activity in open field test and comparable score in cocaine-induced conditioned place preference, the sucrose group showed higher cocaine-induced locomotor sensitivity as compared with the chow group. The anxiety level and the performance in vocal-cue induced fear memory were similar between these two groups in elevated plus maze and fear conditioning tests, respectively. Taken together, our work indicates that sucrose experience promotes the rats' motivation for cocaine.
Animals ; Cocaine ; Conditioning, Classical ; Conditioning, Operant ; Memory ; Motivation ; Rats ; Reward ; Self Administration ; Sucrose

OBJECTIVES: Craving is the subjectively experienced motivational states inducing ongoing drug use in addicts. It also proceeds or precipitates relapse episode in drug addicts. Alcohol craving may be triggered by exposure to an object, environment, or emotion that a person has come to associate with alcohol consumption. Such stimuli are called alcohol-related cues. Among alcohol-related cues, alcohol-related visual stimuli are simple and reliable methods in inducing alcohol craving. The object of this study is to develop alcohol-related visual stimuli which induce alcohol craving reliably and to investigate the characteristics of alcohol-related visual stimuli in alcoholics. METHODS: First, the authors developed 27 alcohol and drinking color photos as candidate stimuli. Then, 3 photos which induce alcohol craving most were chosen as alcohol-related visual stimuli respectively by alcoholics, alcoholism high risk group and normal control group. The authors compared characteristics, situation and complexity of selected alcohol-related visual stimuli among three groups. RESULTS: 1) 'A glass of Soju', 'Drinking together' and 'A glass of beer, a bottle of beer and a sidedish' were chosen as alcohol-related visual stimuli which induce most craving in alcoholics, alcoholism high risk group and normal control group respectively. 2) Alcohol photo(stationary object) induced craving most in alcoholics in contrast with drinking photo(situation) in social drinkers. Alcoholics clung to alcohol per se, not to atmosphere or situation of drinking, and alcoholism high risk group felt craving by the expectation of drinking situation. Normal control group showed no consistent finding in choosing alcohol-related visual stimuli. CONCLUSION: With these results, the author suggests classical conditioning as psychopathological model of alcohol craving with alcoholics. In contrast with alcoholics, alcohol craving of alcoholism high risk group may be related to alcohol specific memory or positive expectancies about alcohol use. These finding may support different neurobiological mechanisms of alcohol craving between alcoholics and social drinkers.
Alcohol Drinking ; Alcoholics ; Alcoholism ; Atmosphere ; Beer ; Conditioning, Classical ; Cues ; Drinking ; Drug Users ; Glass ; Humans ; Memory ; Recurrence

Previous studies have indicated phase-related differences in conditioned acquisition and extinction. In recent years, many researchers used event-related potential (ERP) technology to assess the extent of the acquisition and extinction. Therefore, this study was aimed to assess the sex- and menstrual cycle-dependent effects on the conditioned acquisition and extinction using ERP technology. Thirty-two females at two phases (menses phase, FM, and luteal phase, FL) of their menstrual cycle and 16 males participated in the experiment. The experiment consisted of two stages: acquisition stage and extinction stage. In the acquisition stage, in the predictable context, a condition stimulus (CS) was always followed by the presentation of a negative picture or a neutral picture; but in the unpredictable context, a CS was paired with a negative picture or a neutral picture 20% of the time. In the extinction stage, only CS was presented. The results showed that at acquisition stage, significant larger P2 amplitudes were recorded in female subjects in FL and FM in comparison with those of males. The female subjects in FL may acquire the strongest CS-US conditional connection. At extinction stage, the female subjects in FL showed larger P2 amplitudes than males, but there were no significant differences in P2 amplitudes between the males and females in FM. The results suggest that the females in FL allocate more attention resources to the acquisition of a conditioned response and delayed extinction. In conclusion, we suggest that female menstrual cycle may modulate conditioned acquisition and extinction processes, and our ERP data may provide an explanation for the premenstrual dysphoric disorder.
Attention ; Conditioning, Classical ; Evoked Potentials ; Extinction, Psychological ; Female ; Humans ; Male ; Menstrual Cycle ; Sex Factors

Animals ; Conditioning, Classical ; Evoked Potentials, Somatosensory ; Fear ; psychology ; Male ; Rats ; Rats, Sprague-Dawley ; Stress, Psychological

This study aimed to assess the level of readiness of student nurses for self-directed learning and their learning styles. It also determined the relationship between the two factors and the relationship of each factor to the respondents' demographic profile. This descriptive- correlational study utilized the Autonomous Learner Index of Abu- Moghli, Khalaf, Halabi & Wardam (2005) to assess the students' level of readiness in self-directed learning, and the Learning Style Inventory of Kolb & Kolb (2005) to assess their learning style type. No sampling technique was used because total population was included covering all 103 regular nursing students of Centro Escolar University for First semester of academic year 2016-2017. The study underwent Ethics Review Board Approval before it was implemented. Results of the study revealed that most of the nursing students were independent learners (52%). There were no dependent learners but since there were several respondents who were uncertain (48%), it is the role of nurse educators to develop their independence in learning. Moreover, all the four types of learning styles namely: Accommodative, Convergent, Assimilative and Divergent; were present showing the variation in learning styles of nursing students. But it was found out that they mostly prefer the Convergent learning style, especially the junior and senior students. The study concluded that there was no relationship between the variables: demographic profile, self-directed learning readiness and learning style. However, the scores of convergent learning style were higher than that of divergent and accommodative in their self-directed learning readiness.

Human ; Male ; Female ; Students, Nursing ; Universities ; Faculty, Nursing ; Learning ; Conditioning, Classical ; Demography

This study aimed to assess the level of readiness of student nurses for self-directed learning and their learning styles. It also determined the relationship between the two factors and the relationship of each factor to the respondents' demographic profile. This descriptive- correlational study utilized the Autonomous Learner Index of Abu- Moghli, Khalaf, Halabi & Wardam (2005) to assess the students' level of readiness in self-directed learning, and the Learning Style Inventory of Kolb & Kolb (2005) to assess their learning style type. No sampling technique was used because total population was included covering all 103 regular nursing students of Centro Escolar University for First semester of academic year 2016-2017. The study underwent Ethics Review Board Approval before it was implemented. Results of the study revealed that most of the nursing students were independent learners (52%). There were no dependent learners but since there were several respondents who were uncertain (48%), it is the role of nurse educators to develop their independence in learning. Moreover, all the four types of learning styles namely: Accommodative, Convergent, Assimilative and Divergent; were present showing the variation in learning styles of nursing students. But it was found out that they mostly prefer the Convergent learning style, especially the junior and senior students. The study concluded that there was no relationship between the variables: demographic profile, self-directed learning readiness and learning style. However, the scores of convergent learning style were higher than that of divergent and accommodative in their self-directed learning readiness.

Human ; Male ; Female ; Students, Nursing ; Universities ; Faculty, Nursing ; Learning ; Conditioning, Classical ; Demography

AIMTo inquire a new credible animal model in studies of startle conditioned reflex.

METHODSThrough the trials of combining a conditioned stimulus (a tone) with an unconditioned stimulus(a foot shock), the startle responses were established in animals by conditioned stimulus. Arterial blood pressure were measured before and after blocking basolateral and lateral amygdala with lidocaine.

RESULTSThe blood pressure was increased by the conditioned stimulus after four days training. When the basolateral amygdala was blocked by lidocaine, the blood pressure was not increased by the conditioned stimulus.

CONCLUSIONThe animal model used and verified in this experiment is a new credible chronic animal model in startle conditioned reflex by measuring arterial blood pressure.

Animals ; Arteries ; physiology ; Blood Pressure ; Conditioning, Classical ; physiology ; Female ; Male ; Models, Animal ; Rats ; Rats, Wistar ; Reflex, Startle ; physiology

OBJECTIVE: To explore the characteristic changes of the peripheral chorda tympanic nerve (CT) electrophysiological responses to salty stimulus and other taste stimuli in rats with the conditioned taste aversion to saltiness. METHODS: Fourteen adult SD male rats were divided into a conditioned taste aversion to salty group (CTA) and a control group (Ctrl) (n=7/group). On the first day of the experiment, rats were given a 0.1 mol/L NaCl intake for 30 min, then, the rats in CTA and Ctrl groups were injected intraperitoneally with 2 ml of 0.15 mol/L LiCl and the same amount of saline respectively. On day 2, 3 and 4, the 30 min consumption of NaCl and distilled water was measured for both groups of rats. On the 4th day after the behavioral test of that day, CT electrophysiological recording experiments were performed on CTA rats and control rats. RESULTS: Compared with the rats in Ctrl group, the electrophysiological characteristics of CT in CTA group rats did not change significantly the responses to the series of NaCl and other four basic taste stimuli (P＞0.05). The amiloride, the epithelial sodium channel blocker, strongly inhibited the response of CT to NaCl in CTA and Ctrl group rats (P＜0.01). CONCLUSION The electrophysiological responses of CT to various gustatory stimuli do not significantly change in rats after the establishment of conditional taste aversion to the saltiness.
Amiloride ; pharmacology ; Animals ; Chorda Tympani Nerve ; physiology ; Conditioning, Classical ; Electrophysiological Phenomena ; Male ; Rats ; Rats, Sprague-Dawley ; Sodium Chloride ; Taste ; physiology

Functional magnetic resonance imaging and positron emission tomography studies have identified brain regions associated with different forms of memory and learning. The purpose of this study was to summarize the results of functional neuroimaging studies to construct brain maps for memory and learning. Working memory is associated with the bilateral prefrontal, anterior cingulate, and temporal, and parietal regions ; semantic memory with the left prefrontal and temporal regions ; episodic memory encoding with the left prefrontal and medial temporal regions ; episodic memory retrieval with the right prefrontal, and posterior midline, and medial temporal regions ; skill learning with the motor, parietal, and subcortical regions ; priming with the fusiform and neocortex ; and classical conditioning with the cerebellum. More recent studies have provided higher specificity, by dissociating the neural correlates of different subcomponents of complex memory tasks and the cognitive roles of different subregions of larger brain areas.
Brain Mapping* ; Brain* ; Cerebellum ; Conditioning, Classical ; Functional Neuroimaging ; Learning* ; Magnetic Resonance Imaging ; Memory* ; Memory, Episodic ; Memory, Short-Term ; Neocortex ; Positron-Emission Tomography ; Rabeprazole ; Semantics ; Sensitivity and Specificity

OBJECTIVETry to observe the plasticity of neuron in primary cortex of rat evoked by conditioned stimulus of different sound level.

METHODSApplying conventional electrophysiological technique of extracellular recording to investigate the plasticity of characteristic frequency (CF) and frequency turning curve (FIC) of neurons in rat auditory cortex (AC) by determining CF shifts of neurons caused by sound stimulus of different sound level.

RESULTSWhen the frequency difference between conditioned stimulus (CS) frequency and the CF of neuron was in 1.0 kHz, the plasticity of CF induced by CS was associated with sound level. The probability of the plasticity of CF evoked by CS of higher sound lever was more than the lower. And the probability was dependent on frequency turning curve (FTC) and almost independent on the sound level of conditioned signal.

CONCLUSIONSound level of conditioned stimulus differs the plasticity of characteristic frequency of neurons in rat auditory cortex.

Acoustic Stimulation ; Animals ; Auditory Cortex ; cytology ; Auditory Perception ; physiology ; Conditioning, Classical ; physiology ; Female ; Male ; Neuronal Plasticity ; physiology ; Neurons ; physiology ; Perceptual Masking ; Rats ; Rats, Sprague-Dawley ; Sound