Discriminated avoidance learning and reversal by goldfish in a shuttlebox using a linear presentation procedure

Goldfish, trained in a shuttlebox with cues and shock controlled by a linear presentation procedure, learned to control prevailing cue states and shock, and thus to discriminatively avoid shock presentation. The linear presentation procedure, adapted for the shuttlebox from the sequence of cue presentation occurring in the Y-maze, utilized three cues on each trial, a trial-start (TS) cue, a shock-paired (S?) cue, and an unpaired (S+) cue. At trial onset (TS cue), the goldfish had 10 sec to respond. The first response produced, via response-contingent programming, either the shock-paired (S?) or unpaired (S+) cue, and subsequent responses produced alternation of S+ and S?. The shock was omitted only if the S+ cue state prevailed 10 sec after trial onset. AU other cue states (TS and S?) were paired with shock. Goldfish learned to respond and control the prevailing cue state so that the S+ cue prevailed at 10 sec posttrial onset for a variety of different color-cue combinations and also learned to reverse their originally learned cue preference when the color cues were reversed. The linear presentation procedure represents an alternative discrimination learning procedure that appears to be free of the interpretational problems encountered in training goldfish in the shuttlebox apparatus with other one- and two-stimulus procedures.     

Classical conditioning of an “avoidance” response in goldfish using a linear presentation procedure

The present study examined the nature of the “avoidance” response in goldfish under the linear presentation procedure (Zerbolio, 1981). With this procedure, shuttling behavior occurring during the presentation of the trial stimulus produces either CS? or CS+, and further occurrence of shuttling within the trial interval (10 sec) changes the value of CS from negative to positive, or vice versa. If the fish remains in the compartment when the prevailing cue state is CS? at the end of the interval, shock can be avoided. With this procedure fish responded to the CS+ more than to the CS? and avoided shock. But fish in one of two control groups, in which responses had no effect in changing the cue state from CS+ to CS?, or vice versa, also showed a clear differentiation. The results were generally in line with the view that the “avoidance” response in fish is acquired through classical conditioning. The contribution of classical conditioning to the acquisition of avoidance response is discussed.     

Further avoidance studies with goldfish: Brightness discrimination and transposition

In two experiments using the shuttlebox apparatus and negative (shock) reinforcement, goldfish learned to discriminate between same color signals differing only in brightness and to choose the brightness level paired with shock-omission to avoid shock. Experiment 1 compared two signal presentation procedures, one presenting only one signal at a time but allowing for successive alternation of signals within a trial (SUC) and the other presenting both signals simultaneously (SIM). SIM performance was superior to SUC in acquisition and showed more positive transfer with signal color changed (CC), more negative transfer with brightness-level—shock pairing reversed (R), and, although attenuated, more negative transfer with both signal color changed and shock pairing reversed (CC + R). Further, SIM relearning following reversal was faster than SUC. In Experiment 2, using the SIM procedure, eight transfer groups were tested for transposition with one of their original acquisition signals replaced in transfer by a signal bearing either the same or the opposite brightness relationship to the retained signal. Four transfer groups showed positive and four showed negative transfer effects, but all eight groups showed transfer performances consistent with a transpositional expectation. The present two experiments alone do not elucidate the mechanisms accounting for either the SIM superiority over SUC in Experiment 1 or the transposition effect in Experiment 2. These experiments show only that the transposition phenomenon can be supported by negative reinforcement procedures, which has not been demonstrated before. Now that techniques exist for producing negatively reinforced transposition, work investigating the underlying mechanisms and comparing them with the mechanisms of positively reinforced transposition can begin.     

Matching and oddity conditional discrimination in the goldfish as avoidance responses: Evidence for conceptual avoidance learning

Goldfish, trained in the avoidance shuttlebox with a variant of the linear discrimination procedure, learned to conditionally discriminate between color signals, both for the matching (M) and oddity (O) criterion forms. Transfer to assess the possibility of concept learning was also tested. In original learning, oddity-trained groups learned faster and reached higher conditional discrimination performance levels than did matching-trained groups. In transfer, various groups were tested with the same criterion (MM or OO) or a shifted criterion (MO or OM), and half of each group retained the same color signals and the remaining half had its color signals changed in transfer. Groups with the same criterion in original learning and transfer (MM or OO), regardless of signal colors, showed comparable positive transfer. Groups with their criterion shifted between original learning and transfer (MO or OM) showed comparable negative transfer, regardless of signal colors. Since both positive- and negative-transfer effects were independent of signal colors, it is clear that what was learned for one set of signal colors transferred to at least one other signal-color set. These findings are consistent with the interpretation that goldfish learned the original conditional discrimination at a conceptual level, and learned about the general matching or oddity relationships between colors, rather than about a specific set of colors.     

Preexposure to situational cues and shock intensity in two-way avoidance learning

Four groups of rats (n = 16) received 65 two-way avoidance learning trials. The groups differed with respect to the amount of exposure (0 or 4 h) to the situational cues of the apparatus prior to avoidance learning and the intensity of shock (.3 or 1.6 mA) during learning. Superior avoidance performance with weak as compared to strong shock was obtained in the nonpreexposed groups. This inverse relationship between avoidance performance and shock intensity, typical of two-way avoidance learning, was eliminated in the preexposed groups. Presumably, a latent inhibition effect occurred in the strong-shock group, which resulted in a retardation of the conditioning of fear to the situational cues and a consequent improvement in performance. The results are consistent with the effective reinforcement theory, which emphasizes in aversive learning the detrimental effect of large amounts of fear remaining following a response.     

Preexposure to situational cues produces a direct relationship between two-way avoidance learning and shock intensity

In Experiment 1, four groups of subjects (n = 16 each) were exposed to the situational stimuli of a shuttlebox apparatus for 4 h. Subsequently, 200 two-way avoidance trials were administered (100/day) with either .3- or 1.6-mA shock and with either small or large reward (presence or absence of visual stimuli following the response). Avoidance performance was directly related to shock intensity on both days and to magnitude of reward on the 2nd day. In Experiment 2, four groups of subjects (n = 24 each) were given 4 h of exposure either to the situational stimuli of the shuttlebox or to a neutral box. Then, 10 two-way avoidance trials were given with 1.6-mA shock. Subsequently, subjects were allowed to escape from one of the shuttlebox compartments to an adjacent safe box. Following preexposure to situational stimuli, avoidance performance was superior whereas escape-from-fear performance was inferior. This latter finding demonstrated that less fear of situational cues was present during avoidance training in the preexposed condition. All of these results support the effective reinforcement theory, an extension of two-factor theory, which emphasizes the importance for avoidance learning of the amount of fear of situational cues present following a response.     

Aversive, appetitive and flavour avoidance responses in the presence of contextual cues

Appetitive, aversive and avoidance responses to a flavoured solution in distinct contexts were examined. Rats placed in either a white or black box were given access to saccharin. Consumption was followed by an injection of a toxin in one but not the other box. Rats showed more aversive responses in anticipation of and during the presentation of saccharin in the box paired with the toxin than in the box paired with vehicle. The reverse was true for appetitive responses. The acquisition of conditioned avoidance paralleled the acquisition of aversive and appetitive responses. These findings demonstrate that the toxin does not have to overlap exposure to contextual cues to produce conditioned aversive responses, that the aversive and appetitive responses to a flavour can be modulated by visually distinct environments that predict the toxin, and that conditioned avoidance and conditioned aversions develop simultaneously during acquisition. Thus, environmental cues can modulate anticipatory nausea and may prove helpful in the control of nausea in clinical settings.     

Maintenance of keypecking in pigeons by a food avoidance but not by a shock avoidance contingency

Response key illuminations were followed by food delivery or shock, and keypecks were programmed to prevent the occurrence of whichever stimulus was scheduled. At high shock intensity, pigeons did not peck: at low shock intensity, pigeons pecked in about half of the trials. When different key colors signaled food and shock trials, pigeons pecked on food trials, thus preventing food delivery, but not on shock trials, thus failing to avoid shock delivery. That pecks occurred despite the fact that they avoided food but did not occur when they avoided shock is taken as evidence that the keypeck is frequently governed by biological predispositions, and not by its consequences.     

外显自尊与内隐自尊对在大学生二语习得过程中的作用

二语习得是大学生语言学习的重要内容,是实现大学生全面发展的必然要求。然而,在现实中,大学生二语习得受到诸多因素的影响,如基础薄弱、文化差异认知差、学习兴趣淡薄等等。外显自尊与内隐自尊是强化大学生二语习得的重要因素,在推动大学生二语习得方面发挥了突出性作用。因此,在实践中,要加强外显自尊与内隐自尊的应用,提高二语习得实效。     

Shock intensity and warning signal effects on several measures of operant avoidance acquisition

Acquisition of both signaled and unsignaled operant avoidance learning was studied in 64 rats as a function of shock intensity, with three different warning signals used in the signaled procedure. In both signaled and unsignaled avoidance, overall response rate was a progressively increasing function of shock intensity. This was due to both an absolute and relative increase in the frequency of responses at shorter interresponse times with increasing shock intensity. Presence of an effective warning signal in the interval immediately preceding shock increased the probability of an avoidance response in this interval, decreased overall response rate, and reduced shock frequency. A buzzer signal proved most effective, followed by tone and light. However, once a warning signal occurred, the probability of an avoidance response to the signal was virtually independent of shock intensity. Also, an index of avoidance efficiency proved to be inversely related to shock intensity.     

Effects of intertrial interval and exteroceptive feedback duration on discriminative avoidance acquisition in the gerbil

A series of studies of shuttlebox-avoidance learning in the gerbil evaluated the efficacy of an exteroceptive feedback stimulus (FS). Experiment 1 assessed the relative effectiveness of a FS at 30- and 90-sec intertriai intervals (ITIs), and found that the FS and warning signal termination contingencies were additive sources of avoidance reinforcement; i.e., they produced “supernormal acquisition” at the short ITI, but not at the 90-sec ITI. The effectiveness of a FS at the 30-sec ITI was further explored in Experiments 2 and 3, in which FS duration was varied in delayed and trace avoidance conditioning, respectively. In both studies, a FS facilitated acquisition but FS duration was not a critical determinant of performance. These results were interpreted in terms of an expectancy account of the informational value of a FS, and the problem of experimentally distinguishing between cognitive and inhibition-of-fear accounts of avoidance learning was discussed.     

The effects of preexposure to a warning or a safety signal on the acquisition of a two-way avoidance response in rats

Rats that were given nonreinforced preexposure to either a warning signal or a safety signal were significantly retarded in the subsequent learning of a two-way shock-avoidance response compared to rats that were not preexposed. These results are consistent with Mackintosh’s “learned-irrelevance” formulation of latent inhibition. They do not support a prediction derived from an extension of Kalat and Rozin’s “learned-safety” hypothesis. These findings suggest that preexposures in the total absence of aversive events do not endow a stimulus with safety properties.     

Overshadowing of geometric cues by a beacon in a spatial navigation task

In three experiments, we examined whether overshadowing of geometric cues by a discrete landmark (beacon) is due to the relative saliences of the cues. Using a virtual water maze task, human participants were required to locate a platform marked by a beacon in a distinctively shaped pool. In Experiment 1, the beacon overshadowed geometric cues in a trapezium, but not in an isosceles triangle. The longer escape latencies during acquisition in the trapezium control group with no beacon suggest that the geometric cues in the trapezium were less salient than those in the triangle. In Experiment 2, we evaluated whether generalization decrement, caused by the removal of the beacon at test, could account for overshadowing. An additional beacon was placed in an alternative corner. For the control groups, the beacons were identical; for the overshadow groups, they were visually unique. Overshadowing was again found in the trapezium. In Experiment 3, we tested whether the absence of overshadowing in the triangle was due to the geometric cues being more salient than the beacon. Following training, the beacon was relocated to a different corner. Participants approached the beacon rather than the trained platform corner, suggesting that the beacon was more salient. These results suggest that associative processes do not fully explain cue competition in the spatial domain.     

Assessing heterogeneous student bodies using a methodology that encourages the acquisition of skills valued by employers

This work compares the results of three assessment systems used in two Spanish universities (the Universidad Politécnica de Madrid and the Universidad Católica de Ávila): the traditional system based on final examinations, continuous assessment with periodic tests and a proposed system (specially designed for heterogeneous student bodies) orientated towards motivating students. This third system involved dividing the syllabus into two different parts: a common core assessed by multiple choice tests, and a specialisation assessed by a literature review, the writing of an article and an oral presentation. The latter skills are highly valued by employers. The proposed system led to a greater pass rate than that achieved by students taking similar courses assessed by the more conventional systems. In addition, the results show that involving students in the assessment process increases their participation in their studies and generates a feeling of satisfaction and justice.     

Conflict avoidance in a university context

This ethnographic study explores patterns of conflict avoidance among university students, professors, administrators and staff. Analysis of their narratives of conflict avoidance suggests that avoidance can be beneficial in some circumstances, depending upon personality issues, cost–benefit analysis, power imbalance, type of work, length of relationship and autonomy.     

Acquisition and extinction of differential responses to signals paired with shock or shock omission in goldfish: Evidence for truly discriminated avoidance learning

Goldfish trained to discriminate between signals paired with shock (S?) and signals paired with shock omission (S+) with a linear presentation procedure, originally learned (OL) to control the signal state of a shuttle box and showed a decided preference for the S+ signal. In Experiment 1, following OL, groups had one OL signal replaced (S+ or S?), both signals replaced (S+ and S?), or the OL signals reversed (S+ and S? reversed) and were then tested in a transfer training procedure. In transfer, groups with one signal replaced maintained discriminated performance at OL levels; the S+ replaced group was slightly superior to the S? replaced group on the first day of transfer. With both OL signals replaced, discrimination dropped to chance performance levels, whereas, with OL signal shock pairing reversed, discrimination performance dropped below chance levels. In Experiment 2, following OL, extinction procedures consisted of turning off the shocker (0% shock) or of shocking 100% or a random 25% of the trials. A fourth extinction procedure (R,) retained the trial start response-dependent shock-omission contingency, but shock differentiating the S+ and S? signals was eliminated entirely. Extinction of the S+/S? discrimination was measured both during extinction training per se and with reversal retraining of the S+/S? discrimination later. Groups for which the OL S+ was paired with shock during extinction extinguished on both measures, but groups for which the OL S? was paired with shock omission did not extinguish, especially as shown by the reversal test procedure. Theoretical implications and the implications for several conditioning procedures are discussed.     

Using sexually explicit material in a therapeutic context

For most of us, sex is a subjective, lived experience that is as unique as our genetic make-up, our upbringing, our thoughts, values, feelings, beliefs and ideas. It is through our erotic interactions, or the absence thereof, that we form aspects of our fluid and mutable erotic paths and identities. Despite the proliferation of sexual imagery throughout our culture, many of us still struggle with what sex means to us, what we do, how we experience it and what that says about who we are as people. Some who struggle with this may seek the services of a psychosexual sex therapist. This paper aims to explain how such services function, why they are necessary and how the use of sexually explicit material, in some psychosexual therapeutic contexts, can help unravel the mixed responses we have to sex and our social conditioning, and enhance our overall relationship to eroticism, pleasure and general well-being.