Influence of Previous Preferences on the Memory of Octopus Vulgaris After Removal of the Vertical Lobe

1965 ◽  
Vol 43 (3) ◽  
pp. 595-603
Author(s):  
J. Z. YOUNG
Keyword(s):  
Discrimination Training ◽  
Octopus Vulgaris ◽  
Vertical Rectangle ◽  
Do So

1. Octopuses from which the vertical lobe had been removed attacked a vertical rectangle more readily than a horizontal one when both shapes were moved vertically. 2. During discrimination training the results differed markedly according to which figure was rewarded with food. 3. When a vertical rectangle was positive the excess of attacks at this figure increased both within and between sessions, the animals showing considerable ability to learn. 4. When a horizontal rectangle was the positive figure the responses to it were at first ‘paradoxical’, the negative shape being attacked more often. There was then improvement within each session, but little if any between the sessions. 5. Octopuses without the vertical lobe quickly ceased to attack crabs shown at 4 min. intervals when shocks were given for attacks, and the effect could still be detected 4 hr. later. 6. When crabs were shown at 8 min. intervals, and shocks given for attacks, there was no decline in attacks over fourteen trials. Fifteen hours later, however, some residual signs of the shocks were evident when trials were resumed at 8 min. intervals. Although all of the animals at first attacked they soon stopped doing so. After a further 15 hr. all attacked again but soon ceased to do so after receiving shocks. 7. Normal animals, by contrast, all ceased to attack the crabs shown at 8 min. intervals after receiving four or five shocks. The memory is much more retentive in normal animals, so that 2 days after receiving shocks the octopuses seldom attacked the crabs.

Interference in Learning and Lesions in the Visual System of Octopus Vulgaris

Behaviour ◽  
1963 ◽  
Vol 21 (3-4) ◽  
pp. 233-244 ◽  
Author(s):  
J.R. Parriss
Keyword(s):  
Nervous System ◽  
Visual System ◽  
Optic Lobe ◽  
The Other ◽  
Octopus Vulgaris ◽  
Black And White ◽  
Vertical Rectangle ◽  
Improved Performance ◽  
Previous Learning ◽  
Better Than

AbstractTwo groups of Octopuses, one normal and one with lesions in the optic lobe system, were trained on a discrimination between horizontal and vertical rectangles followed by a discrimination with a square and a diamond. They were then retrained on the original horizontal and vertical discrimination. A further group of normal animals were trained on a discrimination between the square and the diamond followed by a discrimination with the horizontal and vertical rectangles. They were then retrained on the original square and diamond discrimination. Results were as follows: 1. Animals with lesions in the optic lobe system showed impairment of relearning following the different and more difficult square and diamond discrimination. Normal animals, on the other hand, showed improved performance under these conditions. 2. In the case of both normal and operated animals the square and diamond discrimination (square positive - diamond negative) was learned less well following the horizontal and vertical rectangle discrimination than when it was learned as a first discrimination by the normal animals. The level of learning with diamond positive- square negative was, however, maintained at the same level as the first discrimination. 3. When the square and diamond discrimination was relearned by the normal group, square positive - diamond negative was relearned less well than first learning, and diamond positive-square negative was not affected by previous learning, thus confirming point 2. 4. At the end of training the operated animals discriminated between black and white circles better than they had re-learned the horizontal and vertical rectangles. These findings have been related to theories of analysing mechanisms in the nervous system of octopus.

scholarly journals Evidence that Octopus is Colour Blind

1977 ◽  
Vol 70 (1) ◽  
pp. 49-55 ◽  
Author(s):  
J. B. MESSENGER
Keyword(s):  
Visual Discrimination ◽  
Training Session ◽  
Octopus Vulgaris ◽  
Biochemical Evidence ◽  
Vertical Rectangle ◽  
Physiological And Biochemical

1. Six octopuses were trained on a series of visual discrimination tasks where the discriminanda were presented simultaneously, and where different tasks alternated in a single training session. 2. All the octopuses could make discriminations based on brightness and orientation over the same period of time. 3. Over a period in which all octopuses discriminated a black from a white vertical rectangle none discriminated a yellow vertical rectangle from a grey (of matching brightness). 4. Over a period in which all octopuses discriminated a vertical from a horizontal grey rectangle none discriminated a violet vertical rectangle from a matching grey. 5. The behaviour of the octopuses was qualitatively different in the hue versus grey situations, their attacks being considerably slower and less certain. 6. These results, which agree with previous behavioural findings and a variety of morphological, physiological and biochemical evidence, make it increasingly probable that Octopus vulgaris is colour blind.

Holding replication studies to mainstream standards of evidence

2018 ◽  
Vol 41 ◽  
Author(s):  
Duane T. Wegener ◽  
Leandre R. Fabrigar
Keyword(s):  
Replication Studies ◽  
Replication Research ◽  
Standards Of Evidence ◽  
Do So

AbstractReplications can make theoretical contributions, but are unlikely to do so if their findings are open to multiple interpretations (especially violations of psychometric invariance). Thus, just as studies demonstrating novel effects are often expected to empirically evaluate competing explanations, replications should be held to similar standards. Unfortunately, this is rarely done, thereby undermining the value of replication research.

Electron Microscopy of a Herpesvirus Isolated from Marek's Disease in Duck and Chicken Embryo Fibroblast Cultures

1968 ◽  
Vol 26 ◽  
pp. 222-223 ◽  
Author(s):  
Keyvan Nazerian
Keyword(s):  
Inclusion Bodies ◽  
Chicken Embryo Fibroblast ◽  
Marek's Disease ◽  
Marek’S Disease ◽  
Duck Embryo Fibroblast ◽  
Multinucleated Cells ◽  
Viral Particles ◽  
Infected Cells ◽  
And Control ◽  
Do So

A herpes-like virus has been isolated from duck embryo fibroblast (DEF) cultures inoculated with blood from Marek's disease (MD) infected birds. Cultures which contained this virus produced MD in susceptible chickens while virus negative cultures and control cultures failed to do so. This and other circumstantial evidence including similarities in properties of the virus and the MD agent implicate this virus in the etiology of MD.Histochemical studies demonstrated the presence of DNA-staining intranuclear inclusion bodies in polykarocytes in infected cultures. Distinct nucleo-plasmic aggregates were also seen in sections of similar multinucleated cells examined with the electron microscope. These aggregates are probably the same as the inclusion bodies seen with the light microscope. Naked viral particles were observed in the nucleus of infected cells within or on the edges of the nucleoplasmic aggregates. These particles measured 95-100mμ, in diameter and rarely escaped into the cytoplasm or nuclear vesicles by budding through the nuclear membrane (Fig. 1). The enveloped particles (Fig. 2) formed in this manner measured 150-170mμ in diameter and always had a densely stained nucleoid. The virus in supernatant fluids consisted of naked capsids with 162 hollow, cylindrical capsomeres (Fig. 3). Enveloped particles were not seen in such preparations.

Debates in Dysphagia Management: How Do You Use Evidence-Based Practice in Your Dysphagia Patient Care?

2011 ◽  
Vol 20 (4) ◽  
pp. 121-123
Author(s):  
Jeri A. Logemann
Keyword(s):  
Decision Making ◽  
Patient Care ◽  
Clinical Outcomes ◽  
Clinical Judgment ◽  
Clinical Decision Making ◽  
Evidence Based Practice ◽  
Clinical Decision ◽  
Evidence Based ◽  
Clinical Method ◽  
Do So

Evidence-based practice requires astute clinicians to blend our best clinical judgment with the best available external evidence and the patient's own values and expectations. Sometimes, we value one more than another during clinical decision-making, though it is never wise to do so, and sometimes other factors that we are unaware of produce unanticipated clinical outcomes. Sometimes, we feel very strongly about one clinical method or another, and hopefully that belief is founded in evidence. Some beliefs, however, are not founded in evidence. The sound use of evidence is the best way to navigate the debates within our field of practice.

The Persnickety Pervasiveness of Rating Enhancement in Personality Assessment

2020 ◽  
pp. 1-13
Author(s):  
Alicia A. Stachowski ◽  
John T. Kulas
Keyword(s):  
Response Bias ◽  
Personality Assessment ◽  
Current Paper ◽  
Psychological Measurement ◽  
Shared Sets ◽  
Self Reports ◽  
Original Target ◽  
Target Profile ◽  
Do So ◽  
Normative Influences

Abstract. The current paper explores whether self and observer reports of personality are properly viewed through a contrasting lens (as opposed to a more consonant framework). Specifically, we challenge the assumption that self-reports are more susceptible to certain forms of response bias than are informant reports. We do so by examining whether selves and observers are similarly or differently drawn to socially desirable and/or normative influences in personality assessment. Targets rated their own personalities and recommended another person to also do so along shared sets of items diversely contaminated with socially desirable content. The recommended informant then invited a third individual to additionally make ratings of the original target. Profile correlations, analysis of variances (ANOVAs), and simple patterns of agreement/disagreement consistently converged on a strong normative effect paralleling item desirability, with all three rater types exhibiting a tendency to reject socially undesirable descriptors while also endorsing desirable indicators. These tendencies were, in fact, more prominent for informants than they were for self-raters. In their entirety, our results provide a note of caution regarding the strategy of using non-self informants as a comforting comparative benchmark within psychological measurement applications.

Criterion Shift and Anchoring in a Discrimination Training Paradigm: the Importance of Pre-Training

2008 ◽  
Author(s):  
Sandro Scielzo ◽  
Stephen M. Fiore ◽  
Florian Jentsch ◽  
Sherri A. Rehfeld
Keyword(s):  
Discrimination Training ◽  
Training Paradigm ◽  
Criterion Shift
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