Related Experiment Video
Updated: Jan 31, 2026
09:28
A Within-Subject Experimental Design using an Object Location Task in Rats
Published on: May 6, 2021
5.2K
Tryptophan depletion impairs object-recognition memory in the rat: reversal by risperidone
Trisha A Jenkins1, Jennifer J Elliott, Tara C Ardis
1Division of Psychiatry and Neuroscience, Queen's University Belfast, Northern Ireland, United Kingdom. trisha.jenkins@rmit.edu.au
Behavioural Brain Research
|January 2, 2010
Summary
Chronic tryptophan depletion in rats impairs object recognition memory by reducing central serotonin. This cognitive deficit was reversed by the atypical antipsychotic risperidone, highlighting serotonin
Area of Science:
- Neuroscience
- Pharmacology
- Cognitive Science
Background:
- Tryptophan depletion effectively reduces central serotonergic function.
- Serotonin plays a crucial role in mood and cognitive processes.
- Investigating serotonin's impact on cognition requires controlled depletion methods.
Purpose of the Study:
- To examine the effect of chronic tryptophan depletion on cognitive function.
- To assess the role of central serotonin concentration in object-recognition memory.
- To evaluate the potential of atypical antipsychotics in reversing serotonin-related cognitive impairments.
Main Methods:
- A chronic tryptophan-free diet was administered to male Lister-hooded rats for 21 days.
- Cognitive performance was assessed using the novel object-recognition paradigm.
- Central serotonin levels were measured in the hippocampus, frontal cortex, and striatum.
- The effects of risperidone and haloperidol on cognitive performance were evaluated.
Main Results:
- Chronic tryptophan depletion led to a 40-50% reduction in central serotonin.
- Tryptophan-depleted rats exhibited impaired object-recognition memory.
- Risperidone significantly attenuated the cognitive impairment, while haloperidol did not.
Conclusions:
- Chronic reduction of central serotonin is linked to cognitive deficits.
- Object-recognition memory impairment is associated with decreased serotonin levels.
- Risperidone demonstrates potential in reversing serotonin-mediated cognitive impairments.
Related Concept Videos
01:18Velocity of an Object
199
Understanding how an object moves along a path requires distinguishing between motion over a time span and motion at a precise moment. A useful example is a vehicle traveling along a straight and level path, where its position at any given time is known. The initial step in analyzing this motion is to measure how far the vehicle travels over a fixed time period. This measurement, called average velocity, is computed by dividing the total change in position by the duration over which the change...
199
01:20MOSFET: Depletion Mode
860
Depletion-mode MOSFETs represent a unique subset of MOSFET technology, functioning fundamentally differently from their enhancement-mode counterparts. Unlike enhancement MOSFETs, which require a positive gate-source voltage (Vgs) to turn on, depletion-mode MOSFETs are inherently conductive and "normally on" devices.
The primary characteristic of depletion-mode MOSFETs is their ability to conduct current between the drain and source terminals without gate bias. This inherent conductivity...
The primary characteristic of depletion-mode MOSFETs is their ability to conduct current between the drain and source terminals without gate bias. This inherent conductivity...
860
01:23System of Memory
7.3K
Memory is categorized into three major systems: sensory memory, short-term memory (STM), and long-term memory (LTM). These systems differ in their capacity and the duration for which they can hold information. Sensory memory captures raw sensory input from the environment, holding it for just a few seconds or less. For example, on hearing a brief, loud sound, like a car horn honking, the sound seems to linger in the mind for a moment even after it stops. This is an instance of sensory memory...
7.3K
01:24Working Memory
866
Working memory refers to a combination of components, including short-term memory and attention, that allow an individual to hold information temporarily as we perform cognitive tasks. It is an essential cognitive function that enables the execution of complex tasks such as problem-solving, comprehension, and reasoning. Unlike short-term memory, which simply involves the storage of information for a brief period, working memory involves the active manipulation and processing of this...
866
01:29Potential Due to a Polarized Object
780
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
780
01:24Potential Due to a Magnetized Object
794
Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
The vector...
794