Changes in Textural preferences in Octopus After Lesions

1968 ◽  
Vol 49 (2) ◽  
pp. 401-412
Author(s):  
M. J. WELLS ◽  
J. Z. YOUNG
Keyword(s):  
Discrimination Training ◽  
The Other ◽  
Strong Preference ◽  
Frontal System ◽  
Marked Preference ◽  
Smooth Objects ◽  
Smooth Sphere

1. Octopuses repeatedly tested at alternate trials with rough and smooth spheres, presented without reward take more of the smooth than the rough spheres. The individuals that take most often show the greatest preference. 2. The overall tendency to take decreases within each session of sixteen trials and recovers by the next session some hours later. 3. There is a slight decrease in mean takes over the first few sessions but the level then remains at about 36% over ten sessions of sixteen trials. 4. Animals without vertical lobes tested in the same way without rewards take more often (at 60% of all trials). 5. As with the normals there is a decline in take within each session; Extinction is therefore not exclusively the result of changes in the vertical lobe. 6. The preference for smooth is less marked in animals without the vertical lobes than in normals. 7. Animals with the supraoesophageal lobes split by a vertical cut (‘half-brain animals’) and animals with the supraoesophageal lobes removed except for the buccal and ventral subfrontal take fewer objects than normal octopuses. 8. The same animals show reduction or reversal of the smooth preference manifest in normal octopuses. 9. Removal of the whole of the inferior frontal system produced animals that take more often than normal, at 63% of all trials. These octopuses showed a marked preference for smooth. The system for release of objects is defective in these animals and this may act to give the appearance of excesss of takes of smooth. 10. The fact that bund but otherwise normal octopuses prefer smooth objects was confirmed in a discrimination training experiment. Normal animals trained with a smooth sphere as positive performed better initially than those trained in the other direction, though the asymptote reached was the same for both. 11. Animals without vertical lobes showed in training about the same preference for smooth as normals but were variable. They learned more slowly than normals. 12. Half-brain animals showed a strong preference for rough in training. The animals trained with smooth positive learned very slowly and had not reached the level of those trained with rough positive after 160 trials.

The Median Inferior Frontal Lobe and Touch Learning in the Octopus

1972 ◽  
Vol 56 (2) ◽  
pp. 381-402
Author(s):  
M. J. WELLS ◽  
J. Z. YOUNG
Keyword(s):  
Frontal Lobe ◽  
Visual Learning ◽  
Frontal Lobes ◽  
Learning System ◽  
The Other ◽  
Reverse Direction ◽  
Tactile Learning ◽  
Smooth Objects ◽  
Smooth Sphere ◽  
Do So

1. After removal of the median inferior frontal lobe, blinded octopuses already trained to discriminate by touch between rough and smooth spheres continued to do so, but at a lower level of accuracy. 2. Animals without pre-training showed a strong tendency to take rough objects after this operation and learned to discriminate well only when trained to take rough and reject smooth. 3. When animals with intact inferior frontal lobes were given food in the presence of a smooth sphere they learned to take the smooth; in subsequent extinction tests they continued to take the smooth but soon ceased to take rough objects. 4. Animals without median inferior frontal lobes also increased their tendency to take a smooth object associated with food. But they did not behave in the same way as controls in extinction tests; they continued to take the rough objects even if they had not been rewarded for doing so. 5. Operated animals thoroughly pre-trained to take smooth objects showed some capacity to discriminate these from rough objects in subsequent successive training with food and shock, though continuing to take the rough far more than control animals. 6. Animals without brain damage could be taught to take smooth rather than rough objects on one side, and continued to do so when trained in the reverse direction on the other. There was, however, some lateral interference; performance on the unreversed side was worse after the introduction of reversed training. 7. Animals with lesions to the median inferior frontal lobe failed to learn on the reversal (rough+/smooth-) side, responses to both objects declining progressively as training continued. At the same time as this discrimination by the non-reversal (smooth+/rough-) side continued to develop. There was thus no evidence of lateral transfer in these animals. 8. It was confirmed that tactile learning is still possible after removal of the vertical and basal lobes, but with some decrease in the normal preference for smooth objects. 9. The median inferior frontal is thus not essential for tactile learning, but greatly facilitates it, making some contribution to the acquisition of both positive and negative responses, perhaps by spreading information through both sides of the touch-learning system. The effect of its removal in touch learning can be compared with the effect of vertical lobe removal on visual learning. It is concluded that one function of these parts is to compensate for the intensity of stimulation so that animals do not pay undue attention to brightly reflective or texturally rough objects.

Undergraduate Students Prefer Learning Text and Broadcast Skills Sequentially Versus Concurrently, But Assessments of Their Final Projects Are Mixed

2019 ◽  
Vol 74 (4) ◽  
pp. 468-484
Author(s):  
Laura Castañeda ◽  
Rebecca Haggerty
Keyword(s):  
Undergraduate Students ◽  
The Other ◽  
Strong Preference ◽  
Student Survey

This study examined two sections of “Reporting and Writing I.” One taught writing for text and broadcast concurrently, whereas the other taught these skills sequentially. A student survey found a strong preference for learning subjects sequentially. Outside evaluators assessing final stories rated text projects from students taught sequentially slightly higher than text stories from students taught concurrently, but rated broadcast stories from students taught concurrently slightly higher than broadcast stories from students taught sequentially.

Reactions of a pincer proligand with copper iodide: bridging instead of C–H metalation

2020 ◽  
Vol 98 (9) ◽  
pp. 524-530
Author(s):  
Taghrid Chahrour ◽  
Annie Castonguay ◽  
Paul O. Oguadinma ◽  
Frank Schaper ◽  
Davit Zargarian
Keyword(s):  
Solid State ◽  
The Other ◽  
Strong Preference ◽  
Pincer Complexes ◽  
Divalent Copper ◽  
Copper Iodide ◽  
Tetrahedral Geometry ◽  
Central Carbon ◽  
Copper Center ◽  
Solid State Structures

Various precursors of divalent copper have been treated with the meta-disubstituted phenylene-based proligand POC(H)OP (1,3-(i-Pr2PO)2C6H4) with the objective of preparing classical pincer complexes (POCOP)CuX. However, in no case was such species obtained, presumably owing to the difficult C–H metallation step. Analogous reactions of monovalent precursors were also unsuccessful, whereas reaction of POC(H)OP with CuI under different conditions gave the non-metallated adducts {(μ, κP, [Formula: see text]-POC(H)OP)Cu(μ-Ι)}2, 1, {(μ, κP, [Formula: see text]-POC(H)OP)Cu2(μ-Ι)2(DMAP)2}, 2 (DMAP = 4-dimethylaminopyridine), and {(μ, κP, [Formula: see text]-POC(H)OP)Cu2(μ3-Ι)2}2, 3. Treating 1 with DMAP gave the adduct 2, whereas 3 could be obtained by treating 1 with BuLi or by sublimation of 1. The solid state structures of these complexes revealed the tetrahedral geometry that might be anticipated for the d10 Cu(I) centers, in addition to fairly close I–H distances; on the other hand, no C–H interaction (agostic or otherwise) was observed with the Cu centers in any of these structures. The unsuccessful metallation of the C(2)–H moiety is thought to be a result of the strong preference of monovalent copper center to form bridging interactions with iodide and the POC(H)OP ligand; this appears to prevent the approach of the central carbon of the ligand to the Cu centers.

LABORATORY STUDIES OF THE FOOD PREFERENCES OF SOME ORCHARD CARABIDS (COLEOPTERA: CARABIDAE)

1982 ◽  
Vol 114 (5) ◽  
pp. 431-437 ◽  
Author(s):  
E. A. C. Hagley ◽  
N. J. Holliday ◽  
D. R. Barber
Keyword(s):  
Food Preferences ◽  
Codling Moth ◽  
The Other ◽  
Strong Preference ◽  
Laboratory Studies ◽  
Pterostichus Melanarius ◽  
Amara Aenea

AbstractLaboratory studies of the food preferences of several adult carabids showed that Amara aenea DeG., Anisodactylus sanctaecrucis F., Harpalus affinis Schr., and Stenolophus comma F. were polyphagous and readily fed on the seeds of several weeds as well as on young codling moth larvae and apple maggot pupae. H. affinis also attacked 4th and 5th instar codling moth larvae and pupae more readily than the other species. Pterostichus melanarius III. showed a strong preference for the larger prey such as 5th instar codling moth larvae, earthworms, and scarabaeid larvae. The potential of these species as predators of the codling moth and the apple maggot is discussed.

The Effect of Splitting part of the Brain or Removal of the Median Inferior Frontal Lobe on Touch Learning in Octopus

1969 ◽  
Vol 50 (2) ◽  
pp. 515-526
Author(s):  
M. J. WELLS ◽  
J. Z. YOUNG
Keyword(s):  
Frontal Lobe ◽  
Anterior Part ◽  
Posterior Part ◽  
Tactile Discrimination ◽  
Learning Mechanism ◽  
Marked Preference ◽  
Smooth Objects ◽  
The Brain ◽  
Correct Discrimination ◽  
Good Transfer

1. Octopuses with the whole supraoesophageal lobe divided in the mid-line show a lesser preference for smooth objects than normals. 2. Learning of a simple successive tactile discrimination can proceed as fast in such a half-brain as in a whole brain. 3. Animals in which the anterior part of the supraoesophageal lobe alone was split also learned approximately as fast as normals. When tested on the untrained side they showed at most slight signs of ‘transfer’. The unsplit vertical lobe system apparently mediates little transfer, either of learning to take or not to take an object. 4. Animals with the posterior part of the supraoesophageal lobe alone split learned less well than normals or those with anterior splits, the deficit being due to the large number of takes of the negative object. Tests on the untrained side showed that good transfer of the capacity for positive and negative learned response occurred through the intact inferior frontal commissures. 5. Animals without the median inferior frontal lobe showed a marked preference for rough objects. Of six trained with smooth positive only two showed increasingly correct discrimination. Four out of seven animals trained with rough positive showed an increasingly correct performance as a result of training. The performance of the others got worse as training proceeded. It is not clear whether this learning deficit is due to the excessive rough preference or to the absence of some part of the learning mechanism owing to removal of the median inferior frontal lobe. 6. Tests on the untrained side of animals without median inferior frontal show no capacity to discriminate. This shows that the median inferior frontal is vital to lateral transfer and confirms that learning cannot readily be transferred through the vertical lobe system.

Secondary Reinforcement and the Discrimination Hypothesis: The Role of Discrimination Training

1963 ◽  
Vol 13 (3) ◽  
pp. 679-686 ◽  
Author(s):  
A. B. Paige ◽  
H. J. McNamara
Keyword(s):  
Discrimination Training ◽  
Secondary Reinforcement ◽  
The Other ◽  
Running Time ◽  
Resistance To Extinction ◽  
Significant Difference ◽  
Discrimination Hypothesis

The purposes of this experiment are further investigation of: the discrimination hypothesis vs secondary reinforcement positions with respect to resistance to extinction; the role of explicit vs non-explicit discrimination training in resistance to extinction. One group of 32 rats was given explicit discrimination training in an L-type runway involving two goal boxes of different brightness. A second group of 32 Ss had non-explicit discrimination training, i.e., an unfastened card in the goal box entrances concealed the cues until S entered the goal box. Ss were always reinforced in the goal box of one brightness and never reinforced in the goal box of the other brightness. During extinction 16 Ss in each of the above groups were extinguished with the positive cue and 16 with the negative cue. Half of these positive cue and negative cue Ss encountered a card in the goal box entrance, and the rest did not. The results showed no significant difference in alley-running or arm-running times in extinction between the positive and negative cue Ss. Using number of trials to a criterion of two successive running times, Ss extinguished with the positive cue showed greater resistance to extinction. The type of discrimination training did not influence extinction results significantly, using running time or number of trials as a criterion. The results were interpreted as generally incompatible with the discrimination hypothesis prediction and only partially in support of a secondary reinforcement position.

Extending collostructional analysis

2004 ◽  
Vol 9 (1) ◽  
pp. 97-129 ◽  
Author(s):  
Stefan Th. Gries ◽  
Anatol Stefanowitsch
Keyword(s):  
The Other ◽  
Strong Preference ◽  
Grammatical Structure ◽  
Future Tense ◽  
Dative Alternation ◽  
Traditional Approaches

This paper introduces an extension of distinctive-collocate analysis that takes into account grammatical structure and is specifically geared to investigating pairs of semantically similar grammatical constructions and the lexemes that occur in them. The method, referred to as `distinctive-collexeme analysis', identifies lexemes that exhibit a strong preference for one member of the pair as opposed to the other, and thus makes it possible to identify subtle distributional differences between the members of such a pair. The method can be applied in the context of what is sometimes referred to as `grammatical alternation' (e.g. the dative alternation), but it can also be applied to other choices provided by the grammar (such as the two future tense constructions in English). The method has two main applications. First, it can reveal subtle differences between seemingly synonymous constructions, many of which are difficult to identify on the basis of more traditional approaches. Second, it can be used to investigate the very notion of `alternation'; we show that many alternations are much more restricted than has hitherto been assumed, and thus confirm the claims of recent, non-derivational views of grammar.

The Behaviour of Larvae and Pupae of Aedes Aegypti (L.) in Light and Temperature Gradients

1957 ◽  
Vol 48 (2) ◽  
pp. 349-357 ◽  
Author(s):  
T. A. Omardeen
Keyword(s):  
Temperature Gradient ◽  
Aedes Aegypti ◽  
Compound Eye ◽  
Fourth Instar ◽  
Temperature Gradients ◽  
The Other ◽  
Advanced Stage ◽  
Sense Organs ◽  
Light Gradient ◽  
Marked Preference

SummaryExperiments with second-, third- and fourth-instar larvae of Aëdes aegypti (L.), as well as pupae, were carried out to determine their behaviour in temperature and light gradients in an experimental trough.When second-instar larvae are subjected to a temperature gradient from 42°C. at one end of the trough to 8°C. at the other, the majority of larvae aggregate over the range of temperature 23–32°C. Third- and fourth-instar larvae and pupae, however, show a marked preference for the range of temperature between 28–32°C.When subjected to a light gradient from 1·08 log foot-lamberts to log foot-lamberts, second- and third-instar larvae show no marked preference for any one light intensity. The majority of fourth-instar larvae, however, aggregate in the darkest region of the trough, and this negative phototactic reaction is very pronounced in the pupae. This behaviour is probably correlated with the development of sense organs as the larvae grow. In the case of light gradients, it is likely that the increasing negative phototactic reaction is due to the increasing sensitivity of the imaginal compound eye which starts developing in the early larval instars and reaches an advanced stage in the pupa.

scholarly journals A Transferrable Change in Preferences of Floral Patterns by Bumblebees through Reward Reversal

2017 ◽  
Vol 30 ◽  
Author(s):  
Vicki Xu ◽  
Catherine Plowright
Keyword(s):  
Discrimination Training ◽  
Radial Maze ◽  
Category Membership ◽  
Bombus Impatiens ◽  
The Other ◽  
Previous Experience ◽  
Floral Stimulus ◽  
Foraging Preferences ◽  
Foraging Decisions ◽  
Artificial Flowers

This study examines the use behavioral transfer across perceptually similar stimuli in bumblebees (Bombus impatiens) and addresses whether foraging judgments about a floral stimulus can change in a way that contradicts direct previous experience with that stimulus. Twenty bees from each of four colonies underwent discrimination training of stimuli placed in a radial maze. Bees were trained to discriminate between two corresponding object and photograph pairs of artificial flowers, where one object and its corresponding photo were rewarding, while another object and its corresponding photo were unrewarding. Following discrimination training, one stimulus from each pair (either the object or the photo) was removed. The predictive reward values of the remaining stimuli were either switched for one group or stayed the same for another. Subsequent testing on the removed stimuli revealed foraging preferences to shift based on experience with the other stimulus in the group. For instance, bees treated a previously unrewarding object as rewarding after learning that the corresponding photograph had become rewarding. Foraging decisions depend not only on previous experience with stimuli, but also category membership.

scholarly journals Imprecise descriptions of Passiflora riparia Martius ex Masters led to redundant descriptions as P. emiliae Sacco, P. crenata Feuillet & Cremers, P. pergrandis Holm-Nielsen & Lawesson and P. fernandezii Escobar

PhytoKeys ◽  
2019 ◽  
Vol 117 ◽  
pp. 9-35
Author(s):  
Maxime Rome ◽  
Geo Coppens d’Eeckenbrugge
Keyword(s):  
South America ◽  
Central America ◽  
Amazon Basin ◽  
The Other ◽  
Similar Species ◽  
Tropical Andes ◽  
Significant Information ◽  
Closely Related Species ◽  
Marked Preference ◽  
Riparian Habitats

Passiflorariparia was incompletely described by Masters, who cited specimens of Martius and Spruce. While Spruce 2191, the unique syntype with an observable corona, exhibits a reduced outermost series of filaments, the accompanying iconography represents two equal outer series. Later descriptions have neither added significant information nor corrected the inconsistency in the corona description, so that four closely related species have been distinguished on the basis of traits not properly documented for P.riparia: P.emiliae (unequal outer series of filaments), P.crenata (bract color), P.pergrandis (flower size and sepal awn length), and P.fernandezii (hypanthium pubescence and shape). The present study compares (i) the descriptions of the above-mentioned taxa and (ii) 43 associated vouchers, as well as live specimens from two associated P.crenata populations. These and other specimens were georeferenced for a comparison of their distribution and habitat. Of the five P.riparia descriptions found in floras, only that of the Flora of Ecuador appears clearly divergent, corresponding in fact to P.tolimana. Those of the four other taxa only differ by unequal corona filaments (except for P.crenata) and the pubescence of floral parts. However, 22 vouchers associated with all these descriptions (including 16 for P.riparia), as well as the live specimens, share both these traits; the other 21 vouchers were uninformative and/or could not be assigned to any of the five species. The wider sample of 62 specimens indicates no significant differences in either geographic or in climatic distribution (lowlands of the Amazon basin), and a marked preference for riparian habitats. Thus, their very close morphology and ecology justify the placement of P.emiliae, P.crenata, P.pergrandis and P.fernandezii as synonyms of P.riparia, designating Spruce 2191 as epitype. The most similar species, P.ambigua (20 specimens mapped), differs in corolla and bract color, as well as a distribution centered along the tropical Andes of South America and in Central America, in more diverse habitats.

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