m² Conduct rect. chapa aislamiento IBER COVER (e=50 mm) en Exterior

In three of the following five studies we investigated the impact of TMR on declarative, emotional, or extinction memory. Therefore, the memory tasks to establish pre-sleep learning are presented in short here before introducing the manuscripts.

3.1.1 Declarative memory

In the first study, we examined the role of sleep in declarative memory consolidation and associated changes in EEG parameters. We experimentally induced declarative, hippocampus-dependent, object-location learning by a task resembling the game “concentration” which consists of 15 card pairs of colored animals and everyday objects. Participants see the cards as gray squares ordered in a checkerboard-like fashion on a computer screen (“the back of the cards”).

The learning task started by presentation of one card of each card pair alone, followed by the simultaneous presentation of the second card of the pair. All card pairs of the set were presented twice. Thereafter, immediate recall took place by presenting one card and the participant had to identify the location of the second card. Independent of the correctness of the trial, visual feedback on the performance was given by displaying the correct location in order to enable re-encoding of the correct card pair location. This procedure was repeated until 60% of the responses were correct. After a card pair was presented, the locations on the screen were replaced again by gray squares to keep guessing probability constant throughout the task. In order to associate the newly learned memory with a cue, a background odor was presented, starting with the presentation of the first card and ending after both cards were

replaced again. During post-sleep retrieval of declarative memory the next morning, the same procedure as during learning was used, but without odor presentation this time.

To analyze differences between the different sleep interventions on memory consolidation, the percentage of the correctly remembered card locations at retrieval was computed, with memory performance in the last pre-sleep run set to 100%.

3.1.2 Emotional memory

In the third study, we investigated the impact of sleep on emotional memory consolidation.

We induced emotional learning with Pavlovian aversive conditioning by establishing an association between neutral conditioned stimuli (CS) and a negative unconditioned stimulus (UCS). As a result of the repeated pairing of the CS (CS+) with the UCS, the neutral stimuli became negatively valenced, and thus emotional. As control condition, other CS (CS-) were never paired with the UCS, and thus kept their neutral valence.

As initially neutral CS, we took eight normalized sounds of the International Affective Digitized Sound (IADS) system. These sounds have durations of 6 s. Aversive learning was created by presenting a negative odor (4-methyl pentanoic acid) with half of the sounds after 3 s (CS+). As a control condition, the odorless vehicle was presented to the other sounds after 3 s (CS-). All CS+ and CS- were presented 10 times, and the reinforcement rate was 80%, which means the CS+ was presented 8 times with the odor and two times with the odorless vehicle.

As measure of emotional learning, we used ratings of UCS expectancy. In a first run, all of the eight odors were presented with odor or vehicle pairing, to habituate participants to the stimuli. After habituation, emotional learning started. In ten runs, each of the sounds was presented for 1 s, and participants were asked to rate their odor expectancy (“How likely will the odor be presented at the end of this sound?”) from one (“very unlikely”) to nine (“very likely”). A rating of five indicated uncertainty (“I do not know”). When they responded by key press, the odor was released three seconds after the sound onset and was perceivable at 4.5 s after sound onset. If they failed to answer within 2 s, they received feedback that they were too slow, the odor was not released, and the trial was re-started. The intertrial interval was randomized between 13 and 17 s.

Recall took place two days later in the evening and the procedure was the same as during learning, but without the presentation of the odor this time.

Emotional memory consolidation was analyzed by computing the difference between expectancy ratings to CS+ and CS- stimuli at the end of learning and the beginning of recall.

The reaction times of these ratings were also analyzed the same way. For learning, we took the last half of the conditioning trials, whereas for recall, we only considered the first trial of each of the eight sounds for this analysis, to avoid extinction effects.

Additionally, in order to determine changes in subjective emotional intensity attributed to the different sounds, emotional reactivity was assessed by four valence and arousal ratings to each of the sounds. Valence and arousal were included in the task and rated immediately before and after learning and recall. Importantly, to avoid extinction when the CS+ stimuli were presented without the UCS, we explicitly instructed the participants that this run will only contain the sounds without odor pairings.

3.1.3 Extinction memory

In the fourth study, we investigated the role of sleep for fear extinction in patients. Therefore, we extinguished fear in anxiety patients: We applied two sessions of in vivo exposure-based group therapy to spider phobic patients. In short, in the first session, the patients first underwent a theoretical session including psychoeducation about spider phobia and its treatment with exposure therapy, fear circuits, avoidance behavior, and group rules. A practical session followed, during which patients first looked at the spider in a wine glass and then touched the spider with a pen. In the second therapy session one week later, the practical session was continued and patients additionally touched the spider with a finger, caught it with a glass, and let it walk over their hand. The therapy sessions were guided by an experienced psychotherapist.

At the end of both sessions, positive feedback rounds took place, during which each participant verbalized their subjective feeling of therapy success and self-efficacy. We presented an odor as background cue during the feedback round of the first session in order to establish an association between this odor and extinction learning.

We assessed the fear of spiders by questionnaires concerning symptoms and intensity of subjective fear of spiders, the ability to approach a spider, and subjective arousal and SCRs to spider pictures. To investigate an impact of sleep on extinction memory, we compared the values of the fear of spider parameters between groups at the beginning, pre-sleep at the end of the first session, post-sleep at the end of the first session, and at the beginning of the second session one week later. Changes in extinction memory were calculated by subtracting the

values between these time points (absolute differences) and as percentage, with the very first measure set as 100% (for the post-sleep interval), or the last measure of session one as 100%

(for the first assessment during session 2) and compared between groups.