Ultrasound Repetition Suppression : Neuronal Adaptation Or Stimulus Expectation? Essay

Following classical conditioning the data show a decrease in variability and in the latency between stimulus presentation and the response. There is also a change in trend from increasing to no trend.

Due to this, it has been deemed difficult to determine which deficit is the consequence of which part of a lesion. To overcome this problem, other methods are being used to aid in the visualisation of memory processes in the healthy parts of the brain. These come in the form of functional neuroimaging studies using Positron Emission Tomography (PET) and Functional Magnetic Resonance Imaging (fMRI). These studies have allowed researchers to target specific memory processes using targeted psychological experiments. However, with all psychological experiments, there are limitations to using neuroimaging equipment. PET and fMRI attain their signals from local changes in blood flow or metabolism correlated with neural activity rather than from brain waves (or signals). The local vascular changes affect the distribution of an injected radionuclide (e.g. O15) in PET or magnetic properties that are blood-oxygen level dependent (BOLD) in fMRI. The indirect measure of neural activity limits the temporal and spatial fidelity of activations.

The findings by Mayr et al. (2003) sparked a debate due to conflicts with the results found by Gratton et al. (1992). Gratton et al. (1992) had previously looked at the possibility of a repetition priming effect and found that there

Using fMRI, the first task will measure initial activation of the amygdala (fear) and anterior cingulate cortex (empathy). All

The study demonstrates that functional connectivity profiles from functional magnetic resonance imaging studies can accurately and consistently identify individual subjects between scan sessions and also task and rest conditions. Data from 126 subjects of six fMRI sessions provided by the Human Connectome Project were used for the primary data set. Each subject was scanned over 2 days (3 sessions each day): consisting of a resting-state session, a working-memory task, and a motor task on the first day; costing a resting-state session, a language task, and an emotion task on the second day. Functional connectivity was mapped in a functional brain atlas consisting of 268 nodes covering the brain. Identification was performed across pairs of scans comparing

The most modern evidence comes from neuroimaging. The N170 ERP was instrumental in highlighting brain activation when viewing face stimuli. The activation patterns helped to locate the fusiform face area (FFA) because N170 was so distinct to faces. In this essay the fMRI research into the FFA will be explored in detail. To prove faces are special, the research aimed to find a correlation between distinct face-processing brain activity and a specific brain region. The FFA was discovered in 1997 by Kanwisher. It was first described as a brain region which only responded to faces. In fact, activation was found for cat faces and cartoon faces (Tong et al, 2000). There was also some very low level activation to animals, houses and

Overall more experiments need to be conducted to be able to generalize this idea and turn it into a fact. And other factors such as past stimulations, the amount of stimulus and the experiment conditions need to be more thoroughly explained to be able to rely on the validity of these

This quantitative quasi-experimental study will employ a single-factor ex-post facto design. Statistical Parametric Mapping (SPM) is a statistic technique that will be used to examine the differences in brain activity recorded functional neuroimging using the neuroimaging techniques (i.e., PET and MRI). The software created by the Wellcome Department of Imaging Neuroscience will be used to conduct this analysis (Daglish et al., 2008).

Neuroscience has been used to study how the brain regulates behavior since its inception. It was not until recently, that these studies were used in the courtroom as proof of guilt. With new innovations in the field of neuroscience, doctors and lawyers are hoping research can lead to a more accurate legal system. Recent work at Stanford University has revealed that under controlled experiments an fMRI can accurately determine if a person is reliving a memory. Researchers concluded that fMRI methods would one day effectively detect lies.

They performed the same procedures each slide and image the same and also only utilized neurons from Layer III. Only analyzing cells from Layer III helped delete any potential alterations or differences found between the various cortex layers. Another strength was that the researchers utilized two different measures, HSD and GLR that were complementary to each other. GLR helps explain the allocation of different neurons in the ROI by using a relative amount that helps to reduce the consequences of shrinkage and other irrelevant factors that don’t pertain to the study. While there were various strengths detected in this article, there were also numerous weaknesses noted as well. The first weakness was the sample size. The researchers included only 19 subjects in their experimental group, which is a relatively small sample size. Utilizing a large sample could help confirm whether or not the results seen in this experiment are actually characteristic of the general population. Another weakness was that the experiment had a large variability in age within the human subjects. To try and rectify this issue, the researchers removed the 3 oldest human subjects from their analysis, as advanced age may have changed their frontal lobe causing the results to be skewed. This decreased their sample size even more so, which may have decreased the validity of their

PETTLEP model, founded upon functional equivalence, is a notion that imagery, motor preparation and performance share common brain mechanisms. Holmes and Collins suggested that to maximise functional equivalence, the physical nature of imagery should

Title: Evaluate experimental and brain-imaging techniques and consider what they tell us about the brain and cognitive behaviour in typical and atypical individuals.

These procedures involved in cognitive neuroscience require high levels of control, therefore are usually conducted in a laboratory setting, thus producing quantitative data that can be easily analysed, (Eysenck and Keane, 2010). Nevertheless, the techniques vary in the precision with which they identify the brain areas active when a task is performed (spatial resolution), and the time course of such activation (temporal resolution).Therefore, several procedures often need to be combined to compensate for limitations, (Sternberg and Wagner, 1999).

Ultrasound or ultrasonography is a medical imaging technique that uses high frequency sound waves. It is a high pitch frequency that cannot be heard by the human ear. In ultra sound the following happens: High frequency sound pulses (1-5megahertz) are transmitted from the ultrasound machine into your body using a probe. The sound wave will travel into your body until it hits an object such as soft tissue and bone. When the sound wave hits these objects some of the wave will be reflected back to the probe. While some waves may carry on further till they hit another object and then reflected back. The probe picks up these reflected sound waves and relays them to the machine. The distance and time from the probe,

in the stimulus frequency results in a decrease in the release of neurotransmitters, further inhibiting the