Positive Feedback, a General Systems Approach to Positive/Negative Feedback and Mutual Causality

1971 ◽  
Vol 35 (2) ◽  
pp. 404
Author(s):  
Lowell Adams ◽  
J. H. Milsum
Keyword(s):  
Negative Feedback ◽  
Positive Feedback ◽  
Systems Approach ◽  
General Systems

scholarly journals Suppression of personality variation in boldness during foraging in three-spined sticklebacks

2021 ◽  
Vol 75 (4) ◽  
Author(s):  
Hannah E. A. MacGregor ◽  
Aislinn Cottage ◽  
Christos C. Ioannou
Keyword(s):  
Negative Feedback ◽  
Risk Taking ◽  
Positive Feedback ◽  
Gasterosteus Aculeatus ◽  
Control Treatment ◽  
Refuge Use ◽  
Individual Level ◽  
Behavioural Type ◽  
State Behaviour

Abstract Consistent inter-individual variation in behaviour within a population, widely referred to as personality variation, can be affected by environmental context. Feedbacks between an individual’s behaviour and state can strengthen (positive feedback) or weaken (negative feedback) individual differences when experiences such as predator encounters or winning contests are dependent on behavioural type. We examined the influence of foraging on individual-level consistency in refuge use (a measure of risk-taking, i.e. boldness) in three-spined sticklebacks, Gasterosteus aculeatus, and particularly whether changes in refuge use depended on boldness measured under control conditions. In the control treatment trials with no food, individuals were repeatable in refuge use across repeated trials, and this behavioural consistency did not differ between the start and end of these trials. In contrast, when food was available, individuals showed a higher degree of consistency in refuge use at the start of the trials versus controls but this consistency significantly reduced by the end of the trials. The effect of the opportunity to forage was dependent on behavioural type, with bolder fish varying more in their refuge use between the start and the end of the feeding trials than shyer fish, and boldness positively predicted the likelihood of feeding at the start but not at the end of the trials. This suggests a state-behaviour feedback, but there was no overall trend in how bolder individuals changed their behaviour. Our study shows that personality variation can be suppressed in foraging contexts and a potential but unpredictable role of feedbacks between state and behaviour. Significance statement In this experimental study, we examined how foraging influences consistency in risk-taking in individual three-spined sticklebacks. We show that bolder individuals become less consistent in their risk-taking behaviour than shyer individuals during foraging. Some bolder individuals reinforce their risk-taking behaviour, suggesting a positive feedback between state and behaviour, while others converge on the behaviour of shyer individuals, suggesting a negative feedback. In support of a role of satiation in driving negative feedback effects, we found that bolder individuals were more likely to feed at the start but not at the end of the trials. Overall, our findings suggest that foraging can influence personality variation in risk-taking behaviour; however, the role of feedbacks may be unpredictable.

scholarly journals Bayesian analysis of time-varying interactions between stock returns and foreign equity flows

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Boubekeur Baba ◽  
Güven Sevil
Keyword(s):  
Stock Returns ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Positive Response ◽  
Time Varying ◽  
Economic Uncertainty ◽  
Foreign Investors ◽  
New Findings ◽  
Net Flows ◽  
Feedback Trading

AbstractThis study discusses the trading behavior of foreign investors with respect to economic uncertainty in the South Korean stock market from a time-varying perspective. We employ a news-based measure of economic uncertainty along with the model of time-varying parameter vector autoregression with stochastic volatility. The empirical analysis reveals several new findings about foreign investors’ trading behaviors. First, we find evidence that positive feedback trading often appears during periods of high economic uncertainty, whereas negative feedback trading is exclusively observable during periods of low economic uncertainty. Second, the foreign investors’ feedback trading appears mostly to be well-timed and often leads the time-varying economic uncertainty except in periods of global crises. Third, lagged negative (positive) response of net flows to economic uncertainty is found to be coupled with lagged positive (negative) feedback trading. Fourth, the study documents an asymmetric response of foreign investors with regard to negative and positive shocks of economic uncertainty. Specifically, we find that they instantly turn to positive feedback trading after a negative contemporaneous response of net flows to shocks of economic uncertainty. In contrast, they move slowly toward negative feedback trading after a positive response of net flows to uncertainty shocks.

scholarly journals A13-2 Identification of negative feedback, positive feedback and feed foward sequences during tilt test in young women with syncope

EP Europace ◽  
2003 ◽  
Vol 4 (Supplement_2) ◽  
pp. B19-B19
Author(s):  
G.A. Ruiz ◽  
J.C. Perfetto ◽  
S. Gallino ◽  
R. Chirife ◽  
A. Guillardot ◽  
...  
Keyword(s):  
Young Women ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Tilt Test

EFFECT OF HYPOTHALAMIC DEAFFERENTATION ON THE CONTROL OF LUTEINIZING HORMONE SECRETION

1970 ◽  
Vol 46 (1) ◽  
pp. 1-7 ◽  
Author(s):  
S. TALEISNIK ◽  
M. E. VELASCO ◽  
J. J. ASTRADA
Keyword(s):  
Luteinizing Hormone ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Hormone Secretion ◽  
Feedback Effect ◽  
Luteinizing Hormone Secretion ◽  
Ovarian Steroids ◽  
Medial Hypothalamus ◽  
Lh Release ◽  
Positive Feedback Effect

SUMMARY The influence that the interruption of the neural afferents to the hypothalamus exerts on ovulation and on the release of luteinizing hormone (LH) was studied in the rat. Animals with retrochiasmatic sections interrupting the neural connexions between the medial hypothalamus and the preoptic area (POA) showed constant oestrus and failed to ovulate. Animals in which the dorsal neural afferents to the POA were transected had oestrous cycles and ovulated normally. The positive feedback effect of progesterone on LH release in spayed animals primed either with 20 μg. oestradiol benzoate or 2·5 mg. testosterone propionate 3 days before was studied. Transection of the dorsal afferents to the POA favoured an increase in plasma LH, but in animals with retrochiasmatic sections the response was abolished. However, the negative feedback effect of ovarian steroids operated after both types of transection because an increase in plasma LH occurred after ovariectomy. It is concluded that the negative feedback effect of ovarian steroids acts on the medial hypothalamus which can maintain a tonic release of gonadotrophins in the absence of steroids. In contrast, the POA involved in the positive feedback effect of progesterone is concerned with the phasic release of LH.

FEEDBACK EFFECTS OF THYROXINE ON THE HYPOTHALAMUS AND PITUITARY OF GOLDFISH, CARASSIUS AURATUS

1971 ◽  
Vol 51 (1) ◽  
pp. 31-39 ◽  
Author(s):  
R. E. PETER
Keyword(s):  
Negative Feedback ◽  
Positive Feedback ◽  
Carassius Auratus ◽  
Feedback Effect ◽  
Inhibitory Factor ◽  
Pituitary Stalk ◽  
Thyroid Activity ◽  
Feedback Effects ◽  
Goldfish Carassius Auratus ◽  
Positive Feedback Effect

SUMMARY The effect on thyroid activity of a systemically ineffective dose of thyroxine (T4) implanted in the hypothalamus or pituitary of goldfish was tested. Thyroid activity was decreased by T4 implantation in either location, indicating that T4 has a negative feedback effect on the pituitary causing a decrease in thyrotrophin secretion, and a positive feedback effect on the hypothalamus stimulating the secretion of thyrotrophin inhibitory factor (TIF). Fish with a T4 or blank-control implant in the pituitary that had a damaged pituitary stalk, as a result of the operative procedures, were hyperthyroid, suggesting either that TIF is more effective in suppressing thyrotroph activity than T4 and that the effect of T4 was masked by the absence of TIF, or, less likely, that T4 negative feedback in the pituitary is not effective independent of TIF. The results were compared with the information about T4 feedback in mammals.

scholarly journals The Spiral of Positive Feedback: Go-Along Interviews About Adolescents’ Perceptions of and Reactions to Alcohol Posts on Social Media

2021 ◽  
pp. 002204262110414
Author(s):  
Robyn Vanherle ◽  
Kathleen Beullens ◽  
Hanneke Hendriks
Keyword(s):  
Social Media ◽  
Interpersonal Communication ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Online Chat ◽  
Public And Private ◽  
Face To Face ◽  
Online Environments

Go-along interviews among adolescents ( N = 26, M age = 16.31, SD = .83) were conducted to examine how adolescents interpret alcohol posts in terms of appropriateness and how this, in turn, plays a role in adolescents’ reactions toward alcohol posts on public and private social media entries. The findings of this study, first, indicate that alcohol posts were classified as appropriate or inappropriate based on the amount of alcohol and the displayed behavior in the post. Second, most posts, including inappropriate ones, received positive or no feedback. Moreover, adolescents deliberately seemed to withhold negative feedback out of fear of being misjudged by peers. Still, negative reactions were expressed more quickly in safer off- and online environments (i.e., face-to-face conversation and online chat messages) because they were visible to close friends only. This is important in view of prevention as it unravels the interesting role of private environments in stimulating negative interpersonal communication.

INTEGRATION OF POSITIVE AND NEGATIVE FEEDBACK LOOPS IN A CRAYFISH MUSCLE

1994 ◽  
Vol 187 (1) ◽  
pp. 305-313
Author(s):  
P Skorupski ◽  
P Vescovi ◽  
B Bush
Keyword(s):  
Negative Feedback ◽  
Positive Feedback ◽  
Motor Neurone ◽  
Chordotonal Organ ◽  
Negative Feedback Loops ◽  
Reflex Pathways ◽  
Motor Neurones ◽  
Receptor Organ ◽  
Group 2

It is now well established that in arthropods movement-related feedback may produce positive, as well as negative, feedback reflexes (Bassler, 1976; DiCaprio and Clarac, 1981; Skorupski and Sillar, 1986; Skorupski et al. 1992; Vedel, 1980; Zill, 1985). Usually the same motor neurones are involved in both negative feedback (resistance) reflex responses and positive feedback reflexes. Reflex reversal involves a shift in the pattern of central inputs to a motor neurone, for example from excitation to inhibition. In the crayfish, central modulation of reflexes has been described in some detail for two basal limb proprioceptors, the thoracocoxal muscle receptor organ (TCMRO) and the thoracocoxal chordotonal organ (TCCO) (Skorupski et al. 1992; Skorupski and Bush, 1992). Leg promotor motor neurones are excited by stretch of the TCMRO (which, in vivo, occurs on leg remotion) in a negative feedback reflex, but when this reflex reverses they are inhibited by the same stimulus. Release of the TCCO (which corresponds to leg promotion) excites some, but not all, promotor motor neurones in a positive feedback reflex. There are at least two ways in which the reflex control of a muscle may be modulated in this system. Firstly, inputs to motor neurones may be routed via alternative reflex pathways to produce different reflex outputs. Secondly, the pattern of inputs to a motor pool may be inhomogeneous, so that activation of different subgroups of the motor pool causes different outputs. Different crayfish promotor motor neurones are involved in different reflexes. On this basis, the motor neurones may be classified into at least two subgroups: those that are excited by the TCCO in a positive feedback reflex (group 1) and those that are not (group 2). Do these motor neurone subgroups have different effects on the promotor muscle, or is the output of the two promotor subgroups summed at the neuromuscular level? To address this question we recorded from the promotor nerve and muscle in a semi-intact preparation of the crayfish, Pacifastacus leniusculus. Adult male and female crayfish, 8-11 cm rostrum to tail, were decapitated and the tail, carapace and viscera removed. The sternal artery was cannulated and perfused with oxygenated crayfish saline, as described previously (Sillar and Skorupski, 1986).

Signals from the Goal

Runaway ◽  
2017 ◽  
Author(s):  
Anthony Chaney
Keyword(s):  
Negative Feedback ◽  
Positive Feedback ◽  
Scientific Inquiry ◽  
Outer Space ◽  
Physical Models ◽  
A Value ◽  
William Bateson ◽  
Theories Of Evolution ◽  
The Relationship

This chapter places Bateson's work with dolphins within a broader 1960s "dolphin mystique"--a cultural site where anxieties over modern science’s physical models went unresolved. Most associated with scientist John C. Lilly, the dolphin mystique had futurist, utilitarian, and romantic components, also found in a similar "outer space mystique." The chapter shows how Lilly's and Bateson's research goals differed through a further substantiation of the sources of Bateson's thought: the Macy Conferences on Cybernetics (his theory of play, the concepts of positive feedback, negative feedback, servomechanisms, and the naturalization of teleology); and his father William Bateson and his career amid the ongoing conflict between Darwinist and Lamarckian theories of evolution. In Hawaii, Bateson expressed his isolation from potential peers and research frustrations in letters to old friend and Darwin granddaughter/scholar Nora Barlow. This isolation, however, allowed Bateson to articulate a justification for scientific inquiry that was neither utilitarian nor a value-neutral pursuit of truth, but an effort to establish an accurate depiction of the relationship between nature and the human self, which he called the riddle of the Sphinx.

Phase-dependent reversal of reflexes mediated by the thoracocoxal muscle receptor organ in the crayfish, Pacifastacus leniusculus

1986 ◽  
Vol 55 (4) ◽  
pp. 689-695 ◽  
Author(s):  
P. Skorupski ◽  
K. T. Sillar
Keyword(s):  
Motor Neurons ◽  
Negative Feedback ◽  
Positive Feedback ◽  
Motor Output ◽  
Dependent Manner ◽  
Muscle Receptor ◽  
Reflex Pathways ◽  
Receptor Organ ◽  
Positive And Negative Feedback ◽  
Central Excitability

Both negative feedback, resistance reflexes and positive feedback, assistance reflexes are mediated by the thoracocoxal muscle receptor organ (TCMRO) in the crayfish, depending on the central excitability of the preparation. In this paper we present evidence that the velocity-sensitive afferent T fiber of the TCMRO may elicit either resistance or assistance reflexes in different preparations. In preparations displaying assistance reflexes, the S and T fibers of the TCMRO exert reciprocal effects on leg motor neurons (MNs). The S fiber excites promotor MNs (negative feedback) and inhibits remotor MNs, the T fiber excites remotor MNs (positive feedback) and inhibits promotor MNs. During reciprocal motor output of promotor and remotor MNs, reflexes mediated by the TCMRO are modulated in a phase-dependent manner. The TCMRO excites promotor MNs during their active phases (negative feedback) but inhibits them during their reciprocal phases. Remotor MNs are excited by the TCMRO during their active phases (positive feedback). It is proposed that depolarizing central inputs that occur in the S and T fibers at opposite phases of the motor output cycle (21) facilitate the output effects of each afferent in alternation, effectively mediating a phase-dependent shift between the effects of one afferent and the other. The implications of central modulation of reflex pathways and the possible functions of positive and negative feedback reflexes during locomotion are discussed.

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