<P> Short - term memory refers to temporary storage of small amounts of information over short delays . Digit span refers to the proposed number of pieces of information (5 - 9) that can be held in short - term memory . This is also referred to as the magic number seven--plus or minus two . Any more pieces of information than this, and newer items replace previous items . Alcohol intoxication has been found to have dissociative effects on short - term memory and cognitive functioning . </P> <P> Alcohol affects brain functioning . Neurochemical changes occurring in the anterior cingulate are correlated with altered short - term memory functions in the brains of young alcoholic men . fMRIs of alcohol - dependent women displayed significantly less blood oxygen in the frontal and parietal regions, especially in the right hemisphere . This is supported by findings of short - term memory impairment by lesions of the parietal lobe and prefrontal cortex . Associations between Third ventricle volume and cognitive performance on memory tests have been found in alcoholics . Specifically, increases in third ventricular volume correlate with a decline in memory performance . </P> <P> Short - term memory is commonly tested with visual tasks . Short - term memory, especially for non-verbal and spatial material, are impaired by intoxication . Alcohol decreases iconic memory (a type of visual short - term memory). With BACs between 80--84 mg / dl, more intrusion errors occur in a delayed recall task compared to a control group . Intrusion errors, which represent reflective cognitive functioning, occur when irrelevant information is produced . Alcoholics have less control of inhibiting intrusions . Acute alcohol intoxication in social drinkers caused more intrusion errors in delayed recall tasks than in immediate free recall tasks . Acute alcohol intoxication increases susceptibility to interference, which allows for more intrusion errors when there is a short delay . Free recall (given list of words then asked to recall list) is significantly lower and therefore impaired by alcohol intoxication . Encoding deficits were found in verbal free recall and recognition tasks under the influence of alcohol . A discrimination task found significant alcohol - related impairments in depth perception and in visual short - term memory . State - dependent learning and relearning studies in male heavy drinkers demonstrate that the condition of intoxication while learning and sobriety when tested caused a performance deficit in free recall tasks . These findings are supportive of alcohol - induced storage deficits (not retrieval deficits). The effects of acute alcohol consumption on visual short - term memory, stereoscopic depth perception, and attention were studied . A 33% alcohol condition showed significant impairments in depth perception and in visual short - term memory (assessed by the vernier discrimination task). </P> <P> Working memory allows one to keep things in mind while simultaneously performing complex tasks . It involves a system for the temporary storage and manipulation of information, forming a crucial link between perception and controlled action . Evidence suggests that working memory involves three components: the central executive which controls attention, the visuo - spatial sketchpad which holds and manipulates spatial information, and the phonological loop which performs a similar function for auditory and speech - based information . </P>

Which parts of the brain when impaired by alcohol affect memory