Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Pharmacokinetic–Pharmacodynamic Relationship: Dose to Pharmacological Effect

Pharmacokinetic–Pharmacodynamic Relationship: Dose to Pharmacological Effect

A drug’s dosage and pharmacokinetic properties determine how quickly it acts, how intense its effects are, and how long it lasts. Higher doses increase drug concentration at receptor sites, producing a hyperbolic curve when pharmacologic response is plotted against drug dose. Converting this scale to a log-linear format results in a sigmoidal curve, better representing dose–response relationships.For drugs following a one-compartment model, the pharmacologic response is directly proportional to...

Pharmacodynamic Models: Logarithmic Concentration–Effect Model

Pharmacodynamic Models: Logarithmic Concentration–Effect Model

The log-linear model is a pharmacological framework used to describe the relationship between drug concentration and its effect. This model is particularly relevant when the observed effects range between 20% and 80% of the drug’s maximum effect (Emax), where a near-linear relationship is observed between the log of drug concentration and the measured effect. However, the log-linear model does not predict the maximum possible effect (Emax) or the effect at zero drug concentration, limiting its...

Exponential Equations with Logarithms: Problem Solving

Exponential Equations with Logarithms: Problem Solving

In ecological studies, exponential models are often used to predict how populations grow over time under favorable conditions. These models assume that the growth rate is proportional to the current population, leading to continuous and compounding increases.The model expresses the population as a function of time, combining the initial population with a growth factor raised to an exponent involving the growth rate and time. To estimate how long it takes for a population to reach a specific...

Laws of Logarithms I

Laws of Logarithms I

Logarithms are fundamental mathematical operations that serve as the inverse of exponentiation. They provide a means to express how many times a base must be raised to yield a given number. For base 10, often referred to as the common logarithm, the notation is written simply as log. Thus, if 10n = x, then log⁡(x) = n. This relationship makes logarithms especially valuable in simplifying complex calculations involving multiplication, division, and exponentiation.Logarithmic expressions are...

Logarithmic Differentiation

Logarithmic Differentiation

When a car’s weight and driving forces act on a tire, they impose an external load on the rubber material. This load is resisted internally by forces distributed throughout the tire structure, which are defined as stress. The resulting deformation of the rubber due to this stress is quantified as strain. The relationship between stress and strain governs how the tire deforms under load and is central to understanding its mechanical response during operation.Rubber exhibits a nonlinear...

The Integrated Rate Law: The Dependence of Concentration on Time

The Integrated Rate Law: The Dependence of Concentration on Time

While the differential rate law relates the rate and concentrations of reactants, a second form of rate law called the integrated rate law relates concentrations of reactants and time. Integrated rate laws can be used to determine the amount of reactant or product present after a period of time or to estimate the time required for a reaction to proceed to a certain extent. For example, an integrated rate law helps determine the length of time a radioactive material must be stored for its...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Gas-pressurized torrefaction of lignocellulosic solid wastes: Low-temperature deoxygenation and chemical structure evolution mechanisms.

Bioresource technology·2023

Same author

The Role of the Mannich Reaction in Nitrogen Migration during the Co-Hydrothermal Carbonization of Bovine Serum Albumin and Lignin with Various Forms of Acid-Alcohol Assistance.

Molecules (Basel, Switzerland)·2023

Same author

Catalytic pyrolysis of biomass wastes over Org-CaO/Nano-ZSM-5 to produce aromatics: Influence of catalyst properties.

Bioresource technology·2019

Same author

Correlations between hydrochar properties and chemical constitution of orange peel waste during hydrothermal carbonization.

Bioresource technology·2018

Same author

Retrograde facilitation of verbal memory by trihexyphenidyl in healthy elderly with and without the APOE epsilon4 allele.

European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology·2010

Same author

Applications of timing theories to a peak procedure.

Behavioural processes·2007

Search research articles

Related Experiment Video

Updated: Jun 28, 2026

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Published on: January 24, 2013

Do rats represent time logarithmically or linearly?

¹Department of Psychology, Brown University, Providence, RI 02912, USA. Linlin_Yi@Brown.edu

Behavioural Processes

|November 15, 2008

Summary

Rats perceive time logarithmically with consistent variability, not linearly with changing variability. This finding better explains their certainty in judging durations during experiments.

Area of Science:

Psychophysics
Animal Cognition
Behavioral Neuroscience

Background:

Understanding the psychophysical representation of time is crucial for cognitive science.
Previous models proposed linear or logarithmic time scales with varying variability assumptions.

Purpose of the Study:

To investigate whether rats perceive time on a logarithmic or linear scale.
To determine which model, constant variability or scalar variability, best fits rat temporal judgments.

Main Methods:

Utilized a modified temporal bisection procedure with 24 rats.
Employed signal detection theory and analyzed receiver operating characteristic (ROC) curves.
Fitted data to logarithmic (constant variability) and linear (scalar variability) time representations.

More Related Videos

Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats

Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats

Published on: March 17, 2019

Modeling Alcohol Consumption in Rodents Using Two-Bottle Choice Home Cage Drinking and Microstructural Analysis

Modeling Alcohol Consumption in Rodents Using Two-Bottle Choice Home Cage Drinking and Microstructural Analysis

Published on: November 8, 2024

Related Experiment Videos

Last Updated: Jun 28, 2026

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Published on: January 24, 2013

Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats

Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats

Published on: March 17, 2019

Modeling Alcohol Consumption in Rodents Using Two-Bottle Choice Home Cage Drinking and Microstructural Analysis

Modeling Alcohol Consumption in Rodents Using Two-Bottle Choice Home Cage Drinking and Microstructural Analysis

Published on: November 8, 2024

Main Results:

The logarithmic representation of time with constant variability provided a superior fit to the experimental data.
Analysis of response patterns indicated rats' certainty in duration perception.

Conclusions:

Rat time perception aligns better with a logarithmic scale characterized by constant variability.
This suggests a consistent internal clock mechanism for temporal processing in rats.