lisc 390 effects of dph on cognitive ability (kb, ll, sw)

The effects of Diphenhydramine on Cognitive ability : 

The effects of Diphenhydramine on Cognitive ability Kerry Burch, Linda Lee and Shirley Kwong

Introduction : 

Introduction Purpose of lab: Analyzed cognitive processes working memory (short term dynamic) executive function (decision making) learning Attention (reaction time to visual stimulus) AIM: Determine effects of anti-histamine (diphenhydramine) on above cognitive processes

Methods : 

Methods Three participants were tested for cognitive processes. The participants were then given diphrenhydramine mixed into a cup of juice (they were told it was caffeine, an antihistamine or a placebo) The participants were tested further for cognitive ability.

Working Memory - N-Back Test : 

Working Memory - N-Back Test The number of errors is expected to be greater for the 3 back test compared to the 2-back test, due to a greater load on working memory. 2-Back Test 3-Back Test

Executive Function – Stroop Test : 

Red Executive Function – Stroop Test Red The reaction time for the incongruent trials is expected to be longer than for congruent trials. Congruent Incongruent

Learning – Mirror Tracing Task : 

Learning – Mirror Tracing Task It is expected that the number of deviations will decrease during the second trial compared to the first.

Attention- Reaction Time Task : 

Attention- Reaction Time Task Reaction Time Task Simple Go/Nogo It is expected that the reaction time for the go/nogo task will be greater than for simple task. Also the error rate for the go/nogo test will also be greater.

Hypothesis : 

Hypothesis Effects of Diphenhydramine on: Working Memory – decrease meaning an increase in reaction time and an increase in error. Executive Function –Decrease meaning an increase in reaction time and increase in errors. Learning – Decrease in ability to learn meaning increase in error. Attention – increase in reaction time

Working Memory : 

Working Memory Figure 1: Accuracy in n-back memory tests Accuracy decreased between n-back tasks Slight decrease in accuracy between control and DPH for both n-back tasks *

Working Memory : 

Working Memory Figure 2: Reaction times in n-back memory test Reaction times greater in 3-back vs 2-back Increase in time required with DPH in 2-back, decrease with DPH in 3-back *

Executive Function : 

Executive Function Figure 3: Reaction times in stroop task Slightly faster reaction time with DPH in congruent task Increase in reaction time between congruent and non-congruent *

Executive Function : 

Executive Function Figure 4: Accuracy in stroop task Accuracy decreased between congruent and non-congruent tasks Slight differences between control and DPH conditions

Results: Learning Task : 

Results: Learning Task Figure 5: Number of Excursions in the Mirror Tracing Slight increase in errors between trial 1 and trial 2 in control Slight decrease in errors between trial 1 and 2 with DPH Less errors when task performed with DPH than control

Learning Task : 

Learning Task Figure 6: Time Required for Completion in the Mirror Tracing Slight increase in errors between trial 1 and trial 2 in control Slight decrease in errors between trial 1 and 2 with DPH Less errors when task performed with DPH than control

Attention : 

Attention Figure 7: Reaction time to attention task Reaction time for go/nogo task greater than simple visual

Attention : 

Attention Figure 8: Accuracy in go/no-go attention task Slight decrease in accuracy in performance with DPH

Results : 

Results Statistical significance between: 2-back vs 3-back reaction time Percent correct Congruent vs incongruent reaction time

Discussion : 

Discussion Previous studies found: differences in working memory between diphenhydramine and control (Gevins et al.2010) antihistamines induce sleepiness (Tashiro M et al 2002) which then causes decrease in executive function (Anderson B et al 2009) Histamine receptor antagonists impaired learning in rats (Okada A et al, 2010) DPH was found to increase reaction time (Vuurman EF et al, 2004)

Discussion : 

Discussion Classic effects of DPH on cognitive processes were not seen in experiment Possible reasons include: Learning Order of tasks Insufficient trials or participants Participants felt effect of drug and worked harder to stay alert Experiments in published literature are more difficult in comparison Able to pick out smaller changes in cognitive function No control over environmental conditions of participants Blood sugar levels Sleep Work load Mood Tolerance to drug

Conclusion : 

Conclusion Effects of DPH were not significantly seen in the experiment Further testing required with more participants