The Effects of Depression and Stress on Cognitive Functioning

in Humans

Samantha Tobin

Research Question

Is depression

associated with

memory problems?

H Y P O T H E S I S

An individual suffering from depression is more

likely to have an impaired cognitive function than

an individual not suffering from the effects of

stress caused by the disease

P U R P O S Eto investigate the different levels of stress

Effect of stress

each individual’s cognitive function and also

analyze images of the brain

Is there any correlation between the

participant’s responses and

hippocampalvolume?

examine the long-term effects of stress

Introductioncognitive functioning: efficiency of mental

processes such as learning and memory when

subjected to stress.

The brain experiences stress and regulates

“the behavioral, as well as

physiological, responses to the perceived or

actual stress through the hypothalamic outputs

and the autonomic nervous system (McEwen

&Magarinos 2004).

The hypothalamus-pituitary-adrenal (HPA) axis

releases the glucorticoidcortisol when exposed

to stress.

depression can most likely be attributed

to/result in the anxiety, cognitive

insufficiency, and brain atrophy caused by

chronic stress (McEwen et al. 2004)

Stress can be directly associated with an

atypical brain structure and higher

corticosterone levels

MethodsParticipantsHave a random population complete the Beck Depression Inventory (BDI)

Scores below 7= nondysphoric (“healthy”)

Score above 11 = dysphoric (high levels of anxiety and depressive symptoms)

MaterialsBeck Depression Inventory

Cognitive test

3.0 Testa Magnetic Resonance Image (MRI)

ProcedureBDI test: split into two groups (dysphoric and nondysphoric), memorize words and

complete cognitive test.

MRI scan: Compare the brain activity in depressed vs. healthy participants

Statistical AnalysesDifference scores: subtract participants delayed recall scores from immediate recall

scores and compare the difference between the four groups (depressed/healthy

and delayed/immediate recall)

RelevanceConnects the previously distinct

findings of effects of stress and

depression on the brain and

cognitive function

ImportanceUnderstanding Depression