Long-term depression in mammalian brain does not:Group of answer choicescause reversal of long-term potentiation in some neuronsinvolve a stimulus-dependent increase in excitatory postsynaptic potential (EPSP)become induced following changes in intracellular Ca++ in some neuronspersist for at least 60 minutes following inductioncontribute to motor learning in the cerebellum

Question 201 ptsWhich of the following mechanisms is involved in long-term depression (LTD) in the cerebellum?Group of answer choicesactivation of metabotropic glutamate receptorsa reduction in Ca2+ concentration in Purkinje cell dendritesinactivation of Protein Kinase Csensitisation of NMDA receptorssensitisation of AMPA receptors Previous

Which of the following is NOT involved in the induction of long-term depression in Purkinje cells in the cerebellum?Group of answer choicesActivation of NMDA receptorsActivation of parallel fibresActivation of metabotropic glutamate receptorsActivation of AMPA receptorsActivation of climbing fibres

Which of the following is a feature of long term potentiation?Group of answer choiceslong-term potentiation synaptic strengthening lasts about 24 hourshigh levels of glutamate release are necessary over long periods of timeit can only occur in the hippocampus CA3 and CA1 fields pyramidal cellsit occurs in the amygdala and prefrontal cortexit develops when presynaptic and postsynaptic neurons fire simultaneous

Physical modifications important for consolidating memory are particularly apparent in the hippocampus, especially a pathway called the Schaffer Collateral, which contains CA1 (cornu Ammonis) neurons that have been implicated in learning and memory.  To study learning and memory in live mice, scientists use a stimulating electrode to generate brief electrical pulses on the dendrites of CA1 neurons in the Schaffer Collateral pathway and use a recording electrode to measure the excitatory postsynaptic potentials (EPSPs) in the CA1 postsynaptic neurons.In Study 1, researchers used brief low-frequency stimulations (1-5 stimuli per second) to establish a baseline response in the CA1 postsynaptic neurons.  Then, the same dendrites were given a high-frequency stimulation (50-100 stimuli per second), referred to as a tetanus.  The researchers discovered that the high-frequency tetanus induced an increase in the response in postsynaptic CA1 neurons that was long-lasting.  For the control, the researchers established a baseline in a second set of CA1 neurons in the same region but did not give a high-frequency tetanus (Figure 1).Figure 1  CA1 neuron response after a brief tetanus (experimental) or no tetanus (control)In a second behavioral study, mice were housed in either a standard cage (control) or a cage with an enhanced learning environment, including toys and access to a running wheel (experimental condition).  For the first 12 days, both groups of mice received injections of a dye that is incorporated into newly synthesized DNA, thereby providing a biomarker of neurogenesis.Following 30 days in their respective environments, all mice were tested each day for one week in the Morris Water Maze, a test that measures spatial learning and memory consolidation.  Results showed that mice in the experimental condition demonstrated greater improvement on Morris Water Maze performance compared to controls.  When hippocampi were examined, the results revealed that mice in the experimental condition had a greater number of dye-labeled cells than did the controls.W. C. Abraham, B. Logan, J. M. Greenwood, and M. Dragunow ©2002 The Society of Neuroscience, and H. van Praag, B. R. Christie, T. J. Sejnowski, and F. H. Gage ©1999 National Academy of Sciences. Question 12Which of the following conclusions regarding the neuroplasticity of CA1 neurons in the experimental condition is best supported?A.Presynaptic neurons demonstrate synaptic plasticityB.Presynaptic neurons demonstrate structural plasticityC.Postsynaptic neurons demonstrate synaptic plasticityD.Postsynaptic neurons demonstrate structural plasticity

Which of the following is a major function of the cerebellum?Group of answer choicesAlter local circuits of the brainstem and spinal cord via direct projections to the lower motor neuronsAnalyze errors between intended motor output and actual motor outputModulate the output of the basal gangliaRelay information from the primary somatosensory cortex to the primary motor cortexModulate and relay executive decision-making information from the prefrontal cortex to the rest of the cerebral cortex